1. Restricted embryo growth 'predicts miscarriage risk'
Insulin can be used to control sugar levels during pregnancy.
New research finds that ginger's anti-inflammatory properties may play a role in reducing colon cancer risk. The study, published Tuesday in Cancer Prevention Research, found a link between daily ginger supplements and a reduction of inflammation in the colon, which researchers suggest is one step toward better understanding the role ginger root might play in preventing colon cancer. Prior studies in mice and rats have shown that ginger helped prevent the formation of tumors when the animals were exposed to a chemical that causes colon cancer. For the new study, researchers from the University of Michigan Medical School in the US randomly assigned 30 healthy adults to take capsules containing either 2 grams of powered ginger root (about two tablespoons of ground-up ginger root, noted the researchers) or a placebo powder every day for four weeks.
It was done by "flushing out" retired cells that had stopped dividing. They accumulate naturally with age. The scientists belive their findings could eventually "really have an impact" in the care of the elderly. Experts said the results were "fascinating", but should be taken with a bit of caution.
The study, published in Nature, focused on what are known as "senescent cells". They stop dividing into new cells and have an important role in preventing tumours from progressing.
These cells are cleared out by the immune system, but their numbers build up with time. The researchers estimated that around 10% of cells are senescent in very old people.
Scientists at the Mayo Clinic, in the US, devised a way to kill all senescent cells in genetically engineered mice.
The animals would age far more quickly than normal, and when they were given a drug, the senescent cells would die.
The researchers looked at three symptoms of old age: formation of cataracts in the eye; the wasting away of muscle tissue; and the loss of fat deposits under the skin, which keep it smooth.
Researchers said the onset of these symptoms was "dramatically delayed" when the animals were treated with the drug. When it was given after the mice had been allowed to age, there was an improvement in muscle function.
The authors of a study in PLos Genetics said a drug which interrupts Katnal1 could be a reversible contraceptive.
A fertility expert said there was "certainly a need" for such a drug.
Contraception in men is largely down to condoms or a vasectomy.
Infertility search Researchers at the Centre for Reproductive Health at the University of Edinburgh were investigating the causes of male infertility.
They randomly altered the genetic code of mice to see which became infertile. They then traced the mutations which led to infertility, which led them to Katnal1.
One of the researchers Dr Lee Smith said: "If we can find a way to target this gene in the testes, we could potentially develop a non-hormonal contraceptive.
"The important thing is that the effects of such a drug would be reversible because Katnal1 only affects sperm cells in the later stages of development, so it would not hinder the early stages of sperm production and the overall ability to produce sperm.
He said it would be "relatively difficult" to do as the protein lives inside cells, however, he said there was "potential" to find something else that protein worked with, which might be an easier target.
'Holy Grail' Dr Allan Pacey, senior lecturer in andrology at the University of Sheffield, said there was "certainly a need" for a non-hormonal contraceptive for men and that this had been a "Holy Grail" of research for many years.
He added: "The key in developing a non-hormonal contraceptive for men is that the molecular target needs to be very specific for either sperm or other cells in the testicle which are involved in sperm production.
"If they are not, then such a contraceptive could have unwanted side effects on other cells and tissues in the body and may even be dangerous.
"The gene described by the research group in Edinburgh sounds like an exciting new possible target for a new male contraceptive, but it may also shed light on why some men are sub-fertile and why their sperm does not work properly."
Experts cautioned there have since been significant advances in caring for premature babies.
Full-term pregnancies last for around 40 weeks, but one in 13 babies are born prematurely, before 36 weeks.
Heightened risk
Researchers at the Institute of Psychiatry at King's College London and the Karolinska Institute in Sweden analysed data from 1.3m people born in Sweden between 1973 and 1985.
They found 10,523 people were admitted to hospital with a psychiatric disorders, 580 of those had been born prematurely.
The academics showed full-term children had a two in 1,000 chance of being admitted. The risk was four in 1,000 for premature babies born before 36 weeks and six in 1,000 for those born before 32 weeks.
However, she cautioned that the risk was low and the vast majority of premature babies are perfectly healthy.
She told the BBC: "I don't think parents should be worried, but we know that preterm birth confers an increased vulnerability to a variety of psychiatric conditions and perhaps parents should be aware of this and monitor early signs of later more serious problems."
She speculate that "disrupted development" may affect the babies' brains.
Striking
The chief executive of the mental health charity SANE, Marjorie Wallace, said: "We already knew that premature birth may be linked to schizophrenia, but to see evidence linking it to a range of psychiatric conditions which required hospitalisation is striking."
The baby care charity Bliss said it was well-established that early birth can affect the developing brain.
However, its chief executive Andy Cole cautioned that some of the people in the study were born "40 years ago and that neonatal clinical practice to limit neurological damage has been transformed over the past four decades, with significantly improved outcomes seen today."
There have been developments in cooling the brain to reduce any damage as well as improvements in ventilation to ensure enough oxygen is getting to brain.
A study of 1,031 men, published in the journal Neurology, showed those with the most lycopene in their bloodstream were the least likely to have a stroke.
The Stroke Association called for more research into why lycopene seemed to have this effect.
The levels of lycopene in the blood were assessed at the beginning of the study, which then followed the men for the next 12 years.
They were split into four groups based on the amount of lycopene in their blood. There were 25 strokes in the 258 men in the low lycopene group and 11 strokes out of the 259 men in the high lycopene group.
The study said the risk of stroke was cut by 55% by having a diet rich in lycopene.
'Major reduction' Dr Jouni Karppi, from the University of Eastern Finland in Kuopio, said: "This study adds to the evidence that a diet high in fruits and vegetables is associated with a lower risk of stroke.
"The results support the recommendation that people get more than five servings of fruits and vegetables a day, which would likely lead to a major reduction in the number of strokes worldwide, according to previous research."
He said lycopene acted as an antioxidant, reduced inflammation and prevented blood clotting.
Dr Clare Walton, from the Stroke Association, said: "This study suggests that an antioxidant which is found in foods such as tomatoes, red peppers and water-melons could help to lower our stroke risk.
"However, this research should not deter people from eating other types of fruit and vegetables as they all have health benefits and remain an important part of a staple diet.
"More research is needed to help us understand why the particular antioxidant found in vegetables such as tomatoes could help keep our stroke risk down."
The study on 185 people also hinted that patients given the drug developed fewer regions of damaged brain tissue.
The Stroke Association said that it was promising, but needed more research.
Tests in primates had suggested NA-1 prevented brain cells dying when a stroke starved them of oxygen.
A small trial was set up at 14 hospitals in the US and Canada.
Patients who took part were having an operation to repair a brain aneurysm, a weakened blood vessel which could rupture, are at increased risk of a stroke.
Ninety-two people had the drug injected into a vein, while another 93 were injected with salty water.
'Safe' The doctors concluded that NA-1 was safe, with only two patients having mild side effects.
However, brain scans also showed that fewer brain lesions, damaged areas of tissue, formed in patients given the drug.
The doctors involved said the study provided evidence that "neuroprotection is achievable" but said that "a larger trial is necessary to investigate the robustness of the effect".
Prof Markku Kaste, from Helsinki University Central Hospital, said: "Age is the greatest risk factor for stroke. Because of the global population ageing, the number and burden of strokes will increase."
He said previous trials to use drugs to protect the brain had resulted in failure. His said this drug still need to be assessed in much larger clinical trials before its effectiveness was known.
Dr Peter Coleman, from the Stroke Association charity said: "We welcome any treatment that could protect brain cells after a stroke and limit the amount of brain damage. This potential treatment appears promising, but a lot more research is needed."
The trial was funded by the biopharmaceutical companies NoNO and Arbor Vita.
The researchers used experiments and computer modelling to map the passage of air and germs through wards.
They say fitting household extractor fans to windows could maintain sufficient air flow in winter.
The researchers used computer modelling to trace air flows through open and partitioned wards
The study looked at air flow in traditional "Nightingale wards", built as open wards of around 30 beds with opening windows and named after Florence Nightingale, who set out the principles of ward design in the 19th Century.
Balloons filled with carbon dioxide - to represent an airborne pathogen - were popped and the gas followed throughout the ward using tracer devices.
Smoke sticks were also used to visually track the passage of air and wind streams.
The results showed that while the modern trend to partition wards to increase patient privacy changed the air-flow dynamics within a ward, good ventilation could be maintained if windows remained open.
"One of the biggest problems we have in the UK at the moment is that we don't have the money to just knock down every hospital and rebuild it," said Dr Cath Noakes, who led the study.
"We have to deal with what we've got, and many of the wards we've got are going to remain in use for a number of years to come.
"Our research was looking at these big naturally ventilated spaces to see what the risk of infection might be in there.
"What we found was that when the windows are open, these wards are very good.
"But if you close the windows and don't provide any alternative ventilation, the risks go up and they go up about fourfold.
"People are being told to seal up their buildings to save energy.
"We found, if you do that without alternative ventilation systems, you could be increasing the airborne infection risk significantly."
The researchers also looked at what could be done to maintain ventilation in winter months, when the windows had to be shut to keep patients warm.
"We actually used the little extractor fans - the type of thing you get in your bathroom at home.
"We installed those into the window and when we ran those, we found the risks became comparable to a naturally ventilated system."
Co-author Dr Miller Camargo-Valero said: "These simple, low-energy and low-cost solutions could also be of significant benefit for hospitals in the developing world, particularly in countries where airborne diseases such as tuberculosis are a major concern."
Funded by the Engineering and Physical Sciences Research Council, the study was published in the Building and Environment Journal.
Hermetic seals
While the research could help inform practices in older NHS buildings, many newer UK hospital buildings feature no opening windows and complex computer-controlled ventilation systems.
David Docherty, head of estates at the Royal London Hospital, part of Barts Health NHS Trust, told the BBC there were other considerations when it was decided to move the hospital from its old Whitechapel premises to a new adjacent building - namely, air pollution.
"Obviously, the air quality of London meant that we had to consider our patients first and we have to consider the quality of the air that's coming to them," he said.
Instead of opening windows, the new Royal London Hospital has 200 units that bring clean filtered air into the hospital's 3,500 rooms.
19. Nerve cells 're-grown' in rats after spinal injury
US scientists say they have made progress in repairing spinal cord injuries in paralysed rats.
Rats regained some bladder control after surgery to transplant nerve cells into the spinal cord, combined with injections of a cocktail of chemicals.
The study, published in the Journal of Neuroscience, could raise hopes for one day treating paralysed patients.
But UK experts say it will take several years of research before human clinical trials can be considered.
Scientists have tried for decades to use transplants of nerve cells to restore function in paralysed animals by bridging the gap in the broken spinal cord.
However, coaxing the cells to grow and form new connections has proved elusive.
One problem is the growth of scar tissue as the body's responds to injury, which seems to block cell regeneration.
The researchers found for the first time that injured nerve cells could re-grow for "remarkably long distances" (about 2cm).
They said that while the rats did not regain the ability to walk, they did recover some bladder function.
Lead author Dr Jerry Silver of Case Western Reserve Medical School, Cleveland, Ohio, said: "Although animals did not regain the ability to walk, they did recover a remarkable measure of urinary control."
Co-author Dr Yu-Shang Lee of the Cleveland Clinic, Ohio, added: "This is the first time that significant bladder function has been restored via nerve regeneration after a devastating cord injury."
The findings may help future efforts to restore other functions lost after spinal cord injury.
They also raise hope that similar strategies could one day be used to restore bladder function in people with severe spinal cord injuries.
Dr Silver said further animal experiments will be needed to see if the technique could work in humans.
He told BBC News: "If we can show in a larger animal that our technique works and does no additional harm I see no reason why we couldn't move rapidly in humans."
'Remarkable advance'
Commenting on the study, Dr Elizabeth Bradbury of King's College London said several challenges must be overcome before the therapy can be trialled in patients.
"There are a number of challenges before this therapy can be brought to the clinic," she said.
"Nevertheless this is a remarkable advance which offers great hope for the future of restoring bladder function to spinal injured patients and if these challenges can be met we could be reaching clinical trials within three to five years."
Dr John Williams, head of neuroscience and mental health at the Wellcome Trust, said the implications for people are not yet clear.
"This is one of a number of ways that one can approach restoration of bladder function in paralysed patients, but careful studies will be needed to optimise which of the technologies under investigation might be of most benefit to patients."
20. Asthma genetic risk research could lead to future test
They were also more likely to miss school or work and to be admitted to hospital because of their asthma.
At present, there are no tests that can predict which children will recover as they grow older.
'Long way'
What causes Asthma?
"As additional risk genes are discovered, the value of genetic assessments is likely to improve."
He said there was still a long way to go before genetic risk scores could be used routinely in medical practice.
But the study could lead to a better understanding of asthma and how to treat it, he said.
Leanne Reynolds, from the charity Asthma UK, said it was misleading to assume that some children 'grow out' of the condition.
"We know that some children with asthma no longer experience symptoms when they reach adulthood, however... the underlying tendency still remains and so symptoms can still return in later life."
However, she said further research in this area would be welcomed.
"This could mean that in the future we're able to identify those people whose asthma will put them at greatest risk so we can ensure they get the support they need."
Genetic risk prediction for asthma is still in its infancy.”
End Quote Dr Daniel Belsky Duke University
21. 25 Horrible Things That Happen If You Don't Get Enough Sleep
In our 24/7 culture, sleep loss is a major problem. Back in 1942, we averaged almost 8 hours of sleep a night — now that's down to 6.8. (Seven to 9 hours per night are what's generally recommended.)
Almost 40% of Americans get less than 7 hours of sleep a night, a recent Gallup poll found, and an estimated 70 million Americans have a sleep disorder.
Everyone knows that it's important to get enough sleep — but you may not realize just how many things can go wrong when you don't.
Here are 25 unfortunate risks of partial and total sleep deprivation, some more common than others.
1. Irritability
"Complaints of irritability and [emotional] volatility following sleepless nights" are common, a team of Israeli researchers observed. They put those complaints to the test by following a group of underslept medical residents. The study found that the negative emotional effect of disruptive events — things like being interrupted while in the middle of doing something — were amplified by sleep loss.
Source: Sleep, 2005
2. Headaches
Scientists don't yet know exactly why sleep deprivation leads to headaches — but it's a connection doctors have noticed for more than a century. Migraines can be triggered by sleepless nights, and 36 to 58% of people with sleep apnea wake up with "nondescript morning headaches."
Source: Headache, 2003; Headache, 2005
3. Inability to learn
Sleepiness has long been an issue among adolescents. One study of middle school students found that "delaying school start times by one hour, from roughly 7:30 to 8:30, increases standardized test scores by at least 2 percentile points in math and 1 percentile point in reading."
But it's not just kids. Short-term memory is a crucial component of learning, and sleep deprivation significantly impaired the ability of adult volunteers to remember words they'd been shown the day before. In another study, researchers found that while people tend to improve on a task when they do it more than once, this isn't true if they are kept awake after they try it the first time — even if they sleep again before doing it again.
Source: Nature, 1999; Nature Neuroscience, 2000; Education Next, 2012
4. Weight gain
People who are underslept seem to have hormone imbalances that are tied to increased appetite, more cravings for high-calorie foods, a greater response to indulgent treats, and a dampened ability to control their impulses — a very dangerous combination. It's true that you burn more calories when awake, but not nearly enough to cancel out the many excess calories you consume when exhausted.
Source: Journal of Clinical Endocrinology & Metabolism, 2012; PLOS Medicine, 2004; Nature Communications, 2013; PNAS, 2013
5. Poor vision
Sleep deprivation is associated with tunnel vision, double vision, and dimness. The longer you are awake, the more visual errors you'll encounter, and the more likely you are to experience outright hallucinations.
Source: International Journal of Occupational Medicine and Environmental Health, 2010
6. Heart disease
When researchers kept people awake for 88 hours, their blood pressure went up — no big surprise there. But even subjects who were allowed to sleep for 4 hours a night had an elevated heart rate when compared to those getting 8 hours. Concentrations of C-reactive protein, a marker of heart disease risk, increased in those fully and partially deprived of sleep.
Source: Journal of the American College of Cardiology, 2004; PLOS ONE, 2009; Sleep Medicine Reviews, 2012
7. Slowness
Your reaction time is severely impeded when you don't get enough sleep. When researchers gave West Point cadets two tests that require quick decision-making, some were allowed to sleep between the tests, while others were not. Those who had slept did better the second time — those who had not did worse, and their reactions slowed down. A study in college athletes found similar results.
Source: Sleep, 2009; Asian Journal of Sports Medicine, 2012
8. Infection
You know that great thing your immune system does, where when you get an open wound of some kind it doesn't always get infected immediately? Prolonged sleep deprivation and even one night of sleeplessness can impede your body's natural defenses against microorganisms.
Source: American Journal of Physiology, 1993; The FASEB Journal, 1996
9. Economic risk-taking
Planning to make some changes to your portfolio? You might want to make sure you're well-rested. "A single night of sleep deprivation evoked a strategy shift during risky decision making such that healthy human volunteers moved from defending against losses to seeking increased gains," researchers concluded.
Source: The Journal of Neuroscience, 2011
10. Overproduction of urine
When people sleep, the body slows down its normal urine production. This is why most people don't have to pee in the night as much as they do during the day. But when someone is sleep deprived, this normal slowdown doesn't happen, leading to what researchers call "excess nocturnal urine production." This condition may be linked to bed wetting in children and, in adults, it's tied to what's called nocturia — the need to use the bathroom many times during the night.
Source: American Journal of Physiology, 2010; American Journal of Physiology, 2012
11. Distractedness
Having trouble paying attention to what you're reading or listening to? Struggling with anything that requires you to truly focus? "Attention tasks appear to be particularly sensitive to sleep loss," researchers have noted. If you want to stay alert and attentive, sleep is a requirement. Otherwise, you enter "an unstable state that fluctuates within seconds and that cannot be characterized as either fully awake or asleep," and your ability to pay attention is variable at best.
Source: Archives of Italian Biology, 2001; Seminars in Neurology, 2009
12. Less effective vaccines
Vaccines work by spurring your body to create antibodies against a specific virus. But when you don't sleep, your immune system is compromised, and this doesn't work quite as well. In one small study, 19 people were vaccinated against Hepatitis A. Ten of them got 8 hours of sleep the following night, while the rest pulled an all-nighter. Four weeks later, those who had slept normally had levels of Hepatitis A antibodies almost twice as high as those who'd been kept awake.
Another study found that a sleepless night did not have a long-term effect on immunity after a flu vaccine, it concludes that the effect might be specific to certain diseases. "Sleep should be considered an essential factor contributing to the success of vaccination," the Hep A researchers wrote.
Source: Psychosomatic Medicine, 2003; Journal of Immunology, 2011; BMC Immunology, 2012
13. Impaired speech
Severe sleep deprivation might make you sound like a bumbling idiot — much like having way too much to drink. "Volunteers kept awake for 36 hours showed a tendency to use word repetitions and clichés; they spoke monotonously, slowly, [and] indistinctly," one study noted. "They were not able to properly express and verbalize their thoughts."
Source: Sleep, 1997; International Journal of Occupational Medicine and Environmental Health, 2010
14. Colds
If you're wondering why you're sick all the time and seem to pick up every bug that travels around the office, it's probably because you're not getting enough sleep. When a group of 153 people were exposed to a common cold, those who had gotten less than 7 hours of sleep in the two weeks prior were almost 3 times more likely to get sick than those who'd had 8 or more hours of sleep. How well you sleep is also a factor – those who had spent 92% of their time in bed actually asleep were 5.5 times more likely to catch a cold than those who had been peacefully slumbering 98-100% of the time they were in bed.
Source: Archives of Internal Medicine, 2009
15. Gastrointestinal problems
One in 250 Americans suffer from Inflammatory Bowel Disease (IBD), and sleep deficiencies make its symptoms much worse. Regular sleep loss also makes you more likely to develop both IBD and inflammatory bowel syndrome, which affects an estimated 10-15% of people in the U.S. And patients with Crohn's disease were twice as likely to experience a relapse when they weren't getting enough sleep.
Source: World Journal of Gastroenterology, 2013
16. Car accidents
Drowsy driving is often compared to drunk driving: You really shouldn't do either. "Motor vehicle accidents related to fatigue, drowsy driving, and falling asleep at the wheel are particularly common, but often underestimated," one review concluded. Pilots, truck drivers, medical residents, and others required to stay awake for long periods of time "show an increased risk of crashes or near misses due to sleep deprivation."
Source: Seminars in Neurology, 2009
17. Depleted sex drive
Testosterone is an important component of sexual drive and desire in both women and men. Sleeping increases testosterone levels, while being awake decreases them. Sleep deprivation and disturbed sleep, consequently, are associated with reduced libido and sexual dysfunction, and people suffering from sleep apnea are at particular risk.
Source: American Journal of Obstetrics and Gynecology, 2007; Behavioral Brain Research, 2009; Journal of Sexual Medicine, 2009; Sleep Medicine, 2010; Brain Research, 2011
18. Pain
People in pain — especially those suffering from chronic pain — tend not to get enough sleep. This makes sense: Pain can wake you up in the night and make it hard to fall asleep in the first place. But recently, researchers have begun to suspect that sleep deprivation may actually cause pain or at least increase people's sensitivity to pain. One study found that after research subjects were kept awake all night, their pain threshold — the amount of painful stimulus they were able to endure — was lower.
Source: Journal of Sleep Research, 2001; Sleep Medicine Reviews, 2006
19. Diabetes
Being awake when your body wants you to be asleep messes with your metabolism, which in turn increases your risk for insulin resistance (often called "pre-diabetes") and type 2 diabetes. "Interventions to extend sleep duration may reduce diabetes risk," one study in adolescents concluded. And four large studies in adults found a strong association — though not a cause-effect relationship — between regular sleep loss and the risk of developing diabetes, even after controlling for other habits that might be relevant.
Source: Journal of Applied Physiology, 2005; Sleep, 2012; Annals of Internal Medicine, 2012
20. Sloppiness
Most people notice that when they're sleepy, they're not at the top of their game. One study found that one sleepless night contributed to a 20-32% increase in the number of errors made by surgeons. People playing sports that require precision — shooting, sailing, cycling, etc. — also make more mistakes when they've been awake for extended periods of time.
Source: The Lancet, 1998; Physiology & Behavior, 2007
21. Cancer
Scientists are just beginning to investigate the relationship between sleep and cancer, and different kinds of cancer behave differently. But since disrupted circadian rhythm and reduced immunity are direct results of sleep deprivation, it's no surprise that preliminary research seems to indicate that people who don't get enough sleep are at increased risk for developing certain kinds of cancer, most notably colon and breast cancers.
Source: Journal of the National Cancer Institute, 2003; Pathologie-biologie, 2003; Cancer, 2011; AAOHN Journal, 2011
22. Memory problems
Sleep disruptions in the elderly can lead to structural changes in the brain that are associated with impaired long-term memory — and sleep-related memory deficits have been observed in the general adult population as well. As early as 1924, researchers noticed that people who slept more forgot less. Poor sleep and not enough of it have also been linked to higher levels of β-Amyloid, a biomarker for Alzheimer's.
Source: Cell Signal, 2012; Nature Neuroscience, 2013; JAMA Neurology, 2013
23. Genetic disruption
A 2013 study shed some light on why sleep is tied to so many different aspects of our health and wellness. Poor sleep actually disrupts normal genetic activity. After one week of sleeping less than 6 hours per night, researchers found that more than 700 genes were not behaving normally, including some that help govern immune and stress responses.
Some genes that typically cycle according to a daily (circadian) pattern stopped doing so, while others that don't normally follow a daily pattern began doing so. What does this mean? Just one week of less-than-ideal sleep is enough to make some of your genetic activity go haywire.
Source: Proceedings of the National Academy of Sciences, 2013
24. Unhappiness and depression
In a classic study led by Nobel Prize-winning psychologist Daniel Kahneman, a group of 909 working women kept detailed logs of their moods and day-to-day activities. While differences in income up to $60,000 had little effect on happiness, a poor night's sleep was one of two factors that could ruin the following day's mood. (The other was tight deadlines at work.)
Another study reported higher marital happiness among women with more peaceful sleep, although it's hard to say whether happy people sleep better, better sleep makes people happier, or — most likely — some combination of the two. Insomniacs are also twice as likely to develop depression, and preliminary research suggests that treating sleep problems may successfully treat depressive symptoms.
Source: Science, 2004; Behavioral Sleep Medicine, 2009; Journal of Affective Disorders, 2011
25. Death
Many health problems are associated with sleep deprivation and poor sleep, but here's the big one: People who consistently do not get 7-8 hours of sleep are more likely to die during a given time period. Put more simply: We all die eventually, but sleeping too little — or even too much — is associated with a higher risk of dying sooner than you otherwise might.
Source: Sleep, 2010; Sleep Medicine Reviews, 2010
The lifestyles of 91,427 pregnant women in Denmark were analysed for the study
The growth of an embryo during the early stages of pregnancy is linked to its risk of miscarriage, says a University of Nottingham study. Scientists found that 78% of single-baby pregnancies which ended in miscarriage were in the smallest 5% of embryos.
Researchers measured the length of more than 500 single and twin embryos during the first trimester. An expert said the study added to our knowledge of miscarriage risk. The research was presented at the British Fertility Society annual meeting in Leeds. The Nottingham researchers tracked the growth of 247 single and 264 twin embryos conceived through IVF, because this allowed them to know the embryos' precise gestational age.
For each embryo, the distance from the top of the embryo's head to the bottom of its buttocks (the crown-rump length), was measured once during the first trimester using an ultrasound scan. The pregnancy was then monitored until birth. Poor growth Using the measurements, the researchers discovered that poor growth in the first 12 weeks of pregnancy was a good predictor of miscarriage.
They calculated that 77.8% of single embryo pregnancies that miscarried were growth restricted, while 98.1% of single embryo pregnancies that did not miscarry were not growth restricted. This was not the case in twin pregnancies, however, where only 28.6% of pregnancies that miscarried were growth restricted. Ninety-eight per cent of twin pregnancies that did not miscarry were not growth restricted. Dr Shyamaly Sur, who led the research, said the findings should help to identify pregnancies at risk of miscarriage.
"There are various reasons why some embryos show restricted growth in the early stages of pregnancy. It could be down to an abnormality in the foetus or something in the environment of the womb."
Underlying causes "More research is now needed to investigate the relationship between growth and the underlying causes of miscarriage in more detail. We are focusing on how blood flow to the womb lining and embryo quality influence conception rates and subsequent miscarriage." Dr Raj Mathur, consultant gynaecologist at Addenbrooke's Hospital in Cambridge, said it was a very good study which made biological sense.
But he said there were other factors to consider when looking at miscarriage risk.
"We also need to consider the woman's health history, look at the picture of the whole woman.
"This study adds to our knowledge about risk but we also need to look at blood supply to the embryo and whatever genes are passed on from the father too.
The study also found that twin embryos grew at the same rate as single embryos during the first trimester, which was not expected. There is something else going on with twin embryos. We need more research in this area. It could be that twins grow normally and then miscarry. There is something else going on with twin embryos. We need more research in this area. It could be that twins grow normally and then miscarry.
Dr Sur said the research seemed to suggest that embryo growth patterns were similar in non-IVF pregnancies.
2. Diabetes quadruples birth defects risk, say researchers.
Insulin can be used to control sugar levels during pregnancy.
The risk of birth defects increases four-fold if the pregnant mother has diabetes, researchers say.
The Newcastle University study, published in the journal Diabetologia, analysed data from more than 400,000 pregnancies in North East England.
The risk of defects such as congenital heart disease and spina bifida were increased.
National guidelines already recommend having good control over blood sugar levels before trying to conceive. Both Type 1 diabetes, which tends to appear in childhood, and Type 2 diabetes, largely as a result of diet, lead to problems controlling the amount of sugar in the blood. This is known to cause problems in pregnancy, such as birth defects, miscarriage and the baby being overweight due to too much sugar.There is concern that rising levels of diabetes, particularly Type 2, could make the issue worse. Researchers analysed data from 401,149 pregnancies between 1996 and 2008 - 1,677 women had diabetes.
The risk of birth defects went from 19 in every 1,000 births for women without pre-existing diabetes to 72 in every 1,000 births for women with diabetes. Their report said that sugar levels in the run-up to conception were the "most important" risk factor which could be controlled. The lead researcher, Dr Ruth Bell from Newcastle University, told the BBC: "Many of these anomalies happen in the first four to six weeks." She said the number of pregnancies with poor sugar control were "more than we would like".
"It is a problem when the pregnancy is not intended or when people are not aware they need to talk to their doctors before pregnancy," she said.
Guidelines from the National Institute of Health and Clinical Excellence say women should reduce their blood sugar levels to below 6.1% before trying to have a baby.
Sugar levels at conception Risk of birth defect
6.1% One in 34
7% One in 26
8% One in 17
9% One in 12
10% One in nine
Dr Bell said: "The good news is that, with expert help before and during pregnancy, most women with diabetes will have a healthy baby. The risk of problems can be reduced by taking extra care to have the best possible glucose control before becoming pregnant.
The charity Diabetes UK funded the study. Its director of research, Dr Iain Frame, said: "We need to get the message out to women with diabetes that if they are considering becoming pregnant, then they should tell their diabetes healthcare team, who will make sure they are aware of planning and what next steps they should be taking.
"It also highlights the importance of using contraception if you are a woman with diabetes who is sexually active but not planning to become pregnant."
3. Men can inherit a form of heart disease from father via Y chromosome
The Y chromosome determines that a baby will be a boy.
Men can inherit heart disease from their father say scientists who have tracked the condition to the Y chromosome that dads pass to sons.
By studying the DNA of over 3,000 men they found a particular version of the sex chromosome increases the risk of coronary artery disease by 50%.
As many as one in five British men carry this version of Y. And the risk it confers is in addition to other heart risk factors like cholesterol, The Lancet reports. Experts already know that men develop heart disease a decade earlier than women, on average. By the age of 40, the lifetime risk of heart disease is one in two for men and one in three for women.
Lifestyle factors like smoking and blood pressure are important contributors. This latest work suggests the male Y chromosome can also play a role in coronary artery disease - a common form of heart disease that kills thousands each year in the UK. Doctors usually associated the Y chromosome with maleness and fertility but this shows it is also implicated in heart disease.
Dr Maciej TomaszewskiLead researcher, from the University of Leicester, and colleagues studied 3,233 biologically unrelated British men who were already enrolled in other medical studies investigating heart disease risk. When they carried out genetic tests on the men they found that 90% possessed one of two common versions of Y chromosome - named haplogroup I and haplogroup R1b1b2.
And the risk of coronary artery disease among the men carrying the haplogroup I version was 50% higher than in other men. The scientists say they now need to pinpoint precisely which genes on the Y chromosome are responsible. But they believe they already know how they exert their effect - by upsetting a man's immune system.
Dr Maciej Tomaszewski, a clinical senior lecturer at the University's Department of Cardiovascular Sciences, said: "We are very excited about these findings as they put the Y chromosome on the map of genetic susceptibility to coronary artery disease. "Doctors usually associated the Y chromosome with maleness and fertility but this shows it is also implicated in heart disease."
He said, ultimately, the discovery could lead to new ways to treat and prevent heart disease in men, as well as a genetic test to spot those greatest risk. In the meantime, he said men should focus on risk factors that they already have the power to modify themselves, such as getting enough exercise and eating a healthy diet to keep their blood pressure and cholesterol down. Dr Hélène Wilson of the British Heart Foundation, which part-funded the work, said: "Coronary heart disease is the cause of heart attacks, which claim the lives of around 50,000 UK men every year.
"Lifestyle choices such as poor diet and smoking are major causes, but inherited factors carried in DNA are also part of the picture. The next step is to identify specifically which genes are responsible and how they might increase heart attack risk."
4. Pregnant women who eat low-fat yoghurt can increase the risk of their child developing asthma and hay fever, a study says
At the European Respiratory Society conference, researchers will suggest this could be due to an absence of protective fatty acids in yoghurt.
The diets of more than 70,000 Danish women were analysed and their children followed until the age of seven.
Asthma UK says pregnant women should follow a balanced diet.
Pregnant women who ate low-fat yoghurt with fruit once a day were found to be 1.6 times more likely to have children who developed asthma by age seven, compared with children of women who did not eat low-fat yoghurt.
The study also found that the children of these women were more likely to have allergic rhinitis (hay fever) and current asthma symptoms. But the results showed that milk intake during pregnancy was not linked to any increased risk of asthma.
In fact, milk was shown to protect against asthma development.
The absence of fatty acids in low-fat yoghurt could play a part in increasing asthma risk. We would recommend that pregnant women discuss any drastic changes to their diet with their GP. Leanne Metcalf Asthma UK. Ekaterina Maslova, lead study author form the Harvard School of Public Health, who worked with the data at the Statens Serum Institut in Copenhagen, said: "It is a puzzling finding. The absence of fatty acids in low-fat yoghurt may be key to the results. "The results suggest that fatty acids play an important role or it could be that people who ate this kind of yoghurt had similar lifestyle and dietary patterns, but we cannot make any conclusions at this stage. "We need to replicate these results in other studies first. "Leanne Metcalf, director of research at Asthma UK, said there is plenty of evidence to suggest that the pre-natal environment can influence a child's health. "However, the impact of a pregnant woman's diet on her child's health continues to be debated, as it is difficult to assess how particular aspects of a woman's diet during pregnancy are linked to the risk of developing asthma and allergies. "Eating a healthy, balanced diet at any time, but especially during pregnancy is advisable and we would recommend that pregnant women discuss any drastic changes to their diet with their GP first."
5. Be Slimmer, happier and Healthier
A new study has found that people who wake up early are slimmer, happier and healthier than those who get up later in the day. However, people who have the habit of sleeping late night have a higher chance of feeling depressed or stressed and becoming overweight.
6. Daily dose of ginger may cut cancer risk
New research finds that ginger's anti-inflammatory properties may play a role in reducing colon cancer risk. The study, published Tuesday in Cancer Prevention Research, found a link between daily ginger supplements and a reduction of inflammation in the colon, which researchers suggest is one step toward better understanding the role ginger root might play in preventing colon cancer. Prior studies in mice and rats have shown that ginger helped prevent the formation of tumors when the animals were exposed to a chemical that causes colon cancer. For the new study, researchers from the University of Michigan Medical School in the US randomly assigned 30 healthy adults to take capsules containing either 2 grams of powered ginger root (about two tablespoons of ground-up ginger root, noted the researchers) or a placebo powder every day for four weeks.
Before and after the study, the researchers took tissue samples from the lining of the colon. They "tested these samples for chemicals called eicosanoids that increase inflammation in the gut," stated WebMD, noting that the ginger-eating subjects showed reduced inflammation.
Another recent study published in The Lancet found that low doses of aspirin, taken daily and over the long term, cut cases of colorectal cancer by a quarter and the death toll from this disease by a third.
7. Signs of ageing halted in the lab
The onset of wrinkles, muscle wasting and cataracts has been delayed and even eliminated in mice, say researchers in the US.
It was done by "flushing out" retired cells that had stopped dividing. They accumulate naturally with age. The scientists belive their findings could eventually "really have an impact" in the care of the elderly. Experts said the results were "fascinating", but should be taken with a bit of caution.
The study, published in Nature, focused on what are known as "senescent cells". They stop dividing into new cells and have an important role in preventing tumours from progressing.
These cells are cleared out by the immune system, but their numbers build up with time. The researchers estimated that around 10% of cells are senescent in very old people.
Scientists at the Mayo Clinic, in the US, devised a way to kill all senescent cells in genetically engineered mice.
The animals would age far more quickly than normal, and when they were given a drug, the senescent cells would die.
The researchers looked at three symptoms of old age: formation of cataracts in the eye; the wasting away of muscle tissue; and the loss of fat deposits under the skin, which keep it smooth.
Researchers said the onset of these symptoms was "dramatically delayed" when the animals were treated with the drug. When it was given after the mice had been allowed to age, there was an improvement in muscle function.
One of the researchers, Dr James Kirkland, said: "I've never seen anything quite like it."
His colleague Dr Jan van Deursen told the BBC: "We were very surprised by the very profound effect. I really think this is very significant."
The treatment had no effect on lifespan, but that may be due to the type of genetically engineered mouse used.
Eternal youth? The study raises the tantalising prospect of slowing the signs of ageing in humans. However, senescent cells cannot be just flushed out of human beings.
Dr Deursen said: "I'm very optimistic that this could really have an impact. Nobody wants to live longer if the quality of life is poor."
He argued that young people were already clearing out their senescent cells.
"If you can prime the immune system, boost it a little bit, to make sure senescent cells are removed, that might be all it needs.
"Or develop a drug that targets senescent cells because of the unique proteins the cells make."
Dr Jesus Gil, from the Medical Research Council's Clinical Sciences Centre, said the findings needed to be "taken with a bit of caution. It is a preliminary study".
However, he said it was a fascinating study which "suggests if you get rid of senescent cells you can improve phenotypes [physical traits] associated with ageing and improve quality of life in aged humans".
8. Daily aspirin 'blocks bowel cancer'
Daily dose of aspirin should be given to people at high risk of bowel cancer, say scientists.
Two pills a day for two years reduced the incidence of bowel cancer by 63% in a group of 861 at-risk patients, a study reported in The Lancet said.
Newcastle University's Prof Sir John Burn, who led the study, said the evidence "seems overwhelmingly strong" Other experts said the findings added to a growing body of proof that aspirin could be used in the fight with cancer.
The study was conducted on 861 patients with Lynch syndrome, which affects one in every 1,000 people.
They struggle to detect and repair damaged DNA which means they are more likely to develop a range of cancers including those of the bowel, womb and stomach. When looking at all patients in the trial, those in the group given 600 milligrams of aspirin every day developed 19 tumours compared to 34 tumours in the other "control" group, a reduction of 44%.
When the researchers looked at just those patients who took the medication for at least two years the reduction was 63%. There was also an effect on other cancers linked to Lynch syndrome, which fell by half in the treatment group. Prof Sir John Burn, from Newcastle University, said there were 30,000 adults in the UK with Lynch syndrome. If all were given the treatment he said it would prevent 10,000 cancers over 30 years and he speculated that this could possibly prevent 1,000 deaths from the disease.
However, there would also be side effects.
"If we can prevent 10,000 cancers in return for 1,000 ulcers and 100 strokes, in most people's minds that's a good deal," he said.
"People who've got a clear family history of, particularly, bowel cancer should seriously consider adding low dose aspirin to their routine and particularly those people who've got a genetic predisposition."
Aspirin is already well known to reduce the risk of heart attack and stroke in high risk patients.
Audrey Francis describes herself as "a bit of a walking time bomb".
There is a history of cancer in her family and she has been diagnosed with Lynch syndrome. Seventeen years ago she had a hysterectomy. That was when doctors discovered she had not one but two cancers - in the womb and the ovaries. Tests showed she had a chunk of DNA missing which was causing the cancers: "I actually had the inability to stop the cancers developing," she said. She took part in the trial and has since decided to self medicate with aspirin: "I've got my fingers crossed and I'm hoping it'll do the trick for me." Other studies over the past two decades have suggested the pain killer reduced cancer risk, but this was the first randomised control trial, specifically for aspirin in cancer, to prove it.
In 2010, a study suggested patients given aspirin had a 25% lower risk of death during that trial. Prof Peter Rothwell, from Oxford University, who conducted that study said the latest research "certainly helps to build a consistent picture, all pointing in the same direction that there is a link with cancer" Cancer Research UK's Prof Chris Paraskeva said: "This adds to the growing body of evidence showing the importance of aspirin, and aspirin-like drugs, in the fight against cancer."
'Balanced argument'.
One of the questions asked by the research into aspirin was whether healthy people with no family risks should take the drug.
The lower the risk of heart attack or cancer, the lower the benefit of taking aspirin, yet there are still potentially deadly side effects.
Sir John said that it was a "finely balanced argument" and that he decided the risks were worth it for him. "I think where we're headed for is people that are in their 50s and 60s would look very seriously at adding a low dose aspirin to their daily routine because it's giving protection against cancer, heart attack and stroke.
"But if they do that they've got to have their eyes wide open. They will increase their risk of ulcers and gastrointestinal bleeds and very rarely they will have a stroke caused by the aspirin."
His colleague Dr Jan van Deursen told the BBC: "We were very surprised by the very profound effect. I really think this is very significant."
The treatment had no effect on lifespan, but that may be due to the type of genetically engineered mouse used.
Eternal youth? The study raises the tantalising prospect of slowing the signs of ageing in humans. However, senescent cells cannot be just flushed out of human beings.
Dr Deursen said: "I'm very optimistic that this could really have an impact. Nobody wants to live longer if the quality of life is poor."
He argued that young people were already clearing out their senescent cells.
"If you can prime the immune system, boost it a little bit, to make sure senescent cells are removed, that might be all it needs.
"Or develop a drug that targets senescent cells because of the unique proteins the cells make."
Dr Jesus Gil, from the Medical Research Council's Clinical Sciences Centre, said the findings needed to be "taken with a bit of caution. It is a preliminary study".
However, he said it was a fascinating study which "suggests if you get rid of senescent cells you can improve phenotypes [physical traits] associated with ageing and improve quality of life in aged humans".
8. Daily aspirin 'blocks bowel cancer'
Daily dose of aspirin should be given to people at high risk of bowel cancer, say scientists.
Two pills a day for two years reduced the incidence of bowel cancer by 63% in a group of 861 at-risk patients, a study reported in The Lancet said.
Newcastle University's Prof Sir John Burn, who led the study, said the evidence "seems overwhelmingly strong" Other experts said the findings added to a growing body of proof that aspirin could be used in the fight with cancer.
The study was conducted on 861 patients with Lynch syndrome, which affects one in every 1,000 people.
They struggle to detect and repair damaged DNA which means they are more likely to develop a range of cancers including those of the bowel, womb and stomach. When looking at all patients in the trial, those in the group given 600 milligrams of aspirin every day developed 19 tumours compared to 34 tumours in the other "control" group, a reduction of 44%.
When the researchers looked at just those patients who took the medication for at least two years the reduction was 63%. There was also an effect on other cancers linked to Lynch syndrome, which fell by half in the treatment group. Prof Sir John Burn, from Newcastle University, said there were 30,000 adults in the UK with Lynch syndrome. If all were given the treatment he said it would prevent 10,000 cancers over 30 years and he speculated that this could possibly prevent 1,000 deaths from the disease.
However, there would also be side effects.
"If we can prevent 10,000 cancers in return for 1,000 ulcers and 100 strokes, in most people's minds that's a good deal," he said.
"People who've got a clear family history of, particularly, bowel cancer should seriously consider adding low dose aspirin to their routine and particularly those people who've got a genetic predisposition."
Aspirin is already well known to reduce the risk of heart attack and stroke in high risk patients.
Audrey Francis describes herself as "a bit of a walking time bomb".
There is a history of cancer in her family and she has been diagnosed with Lynch syndrome. Seventeen years ago she had a hysterectomy. That was when doctors discovered she had not one but two cancers - in the womb and the ovaries. Tests showed she had a chunk of DNA missing which was causing the cancers: "I actually had the inability to stop the cancers developing," she said. She took part in the trial and has since decided to self medicate with aspirin: "I've got my fingers crossed and I'm hoping it'll do the trick for me." Other studies over the past two decades have suggested the pain killer reduced cancer risk, but this was the first randomised control trial, specifically for aspirin in cancer, to prove it.
In 2010, a study suggested patients given aspirin had a 25% lower risk of death during that trial. Prof Peter Rothwell, from Oxford University, who conducted that study said the latest research "certainly helps to build a consistent picture, all pointing in the same direction that there is a link with cancer" Cancer Research UK's Prof Chris Paraskeva said: "This adds to the growing body of evidence showing the importance of aspirin, and aspirin-like drugs, in the fight against cancer."
'Balanced argument'.
One of the questions asked by the research into aspirin was whether healthy people with no family risks should take the drug.
The lower the risk of heart attack or cancer, the lower the benefit of taking aspirin, yet there are still potentially deadly side effects.
Sir John said that it was a "finely balanced argument" and that he decided the risks were worth it for him. "I think where we're headed for is people that are in their 50s and 60s would look very seriously at adding a low dose aspirin to their daily routine because it's giving protection against cancer, heart attack and stroke.
"But if they do that they've got to have their eyes wide open. They will increase their risk of ulcers and gastrointestinal bleeds and very rarely they will have a stroke caused by the aspirin."
9. Delay cord clamping for baby health, say experts
Waiting a few minutes after delivery to cut the umbilical cord is best for a newborn's health, research suggests.
Delaying cord clamping reduces the risk that the baby will have iron deficiency anaemia without substantial side effects, the authors told the BMJ.
The World Health Organization dropped early clamping from its guidelines some years ago.
But there are no formal guidelines for NHS staff about when the cord should be cut.
A few years ago found many UK hospitals advocate early clamping, as soon as the baby is delivered. Blood boost
Mounting evidence suggests this may not be best practice and could be causing health problems.
Globally, about a quarter of preschool children have iron deficiency anaemia, the most severe form of iron deficiency. In Europe, the prevalence is 3-7%.
This is a significant health problem because it can harm a child's brain development.
A simple solution, say researchers, is to ensure babies get the best start in life by maximising the blood and iron stores they get from the placenta.
Waiting three minutes before clamping the umbilical cord at birth can boost a newborn's blood volume by a third.
In the latest study, experts in Sweden looked at the outcomes of 400 babies born after a low-risk pregnancy.
Some had their umbilical cords clamped after at least three minutes and others had them clamped in less than 10 seconds after delivery.
Routine practice
Babies with delayed clamping had better iron levels at four months of age and were far less likely to suffer newborn anaemia.
And there were no obvious adverse health effects, despite previous concerns raised by researchers about the possibility that delayed clamping could make the baby jaundiced.
The researchers estimate that, for every 20 babies having delayed clamping, one case of iron deficiency would be prevented.
They say that delayed cord clamping "should be considered as standard care for full term deliveries after uncomplicated pregnancies".
The Royal College of Obstetricians and Gynaecologists (RCOG) has no specific recommendation on when the umbilical cord should be clamped, but its scientific opinion paper admits: "Immediate cord clamping became routine practice without rigorous evaluation."
It calls for more research into the area: "Iron deficiency in the first few months of life is associated with neurodevelopmental delay, which may be irreversible. Whether increasing placental transfusion by deferring cord clamping will improve neurodevelopment in early childhood is not known but this hypothesis should be tested in large randomised trials."
Patrick O'Brien, of the RCOG, said the weight of evidence to support delayed clamping was growing and that many more hospitals in the UK were adopting the practice.
"The college will look at this and other evidence and consider if it is enough to change policy."
10
10. Sense of smell 'can be improved through training'
The sense of smell can be improved through training, a study on rats suggests.
The study, published in Nature Neuroscience, also suggests if we do not use our sense of smell, we begin to lose it.
The New York University Langone Medical Center team says their work also raises hopes of reversing loss of smell caused by ageing or disease.
But a UK expert thought that was unlikely.
Impairment in the sense of smell is associated with Alzheimer's disease, Parkinson's disease, schizophrenia, and even normal ageing.
Exactly why smell weakens remains a mystery, but the Langone team have pinpointed a half-inch-sized area of the rat brain called the piriform (olfactory) cortex where the problems appear to occur.
Rewards
The researchers placed thirsty rats in boxes with a snout-sized hole in each of three walls and exposed them to brief blasts of odours through the middle hole.
There were three different smells: a mix of 10 chemicals from fruits, oils, and cleaning agents; the same mixture with one chemical replaced by another; and the same mixture minus one of the chemicals.
When the rodents identified one smell, they were rewarded with a sip of water by going to the hole in the left side wall, for another smell they received water by going to the right side wall.
Rats could readily distinguish between odours when a chemical had been replaced in one mixture, but when one component had simply been removed, they could not differentiate.
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Sense of smell
Sense of smell
- Smell is one of our oldest senses, and the one most closely linked to memory
- It is probably related to simple chemo-sensation exhibited by some of the very first uni-cellular creatures on this planet
- The olfactory bulb, a structure in the brain that receives nerve signals from the nose, has direct connections to other parts of the brain such as the amygdala, which controls memory, and the prefrontal cortex, which is involved in processing thoughts
The researchers anaesthetised the rats and inserted electrodes into their brains.
Within the olfactory bulb, each smell produced a different pattern of electrical activity.
But in the piriform cortex the odours that rats could tell apart produced distinct patterns of activity, while those they could not distinguish produced identical patterns.
The researchers then trained a new group of rats to discriminate between the odours the first animals could not tell apart by rewarding them over and over with sips water for choosing the appropriate hole.
In the rats' piriform cortex, activity patterns elicited by these similar odours were now different as well.
A third group of animals were trained to ignore the difference between odours the first rats could readily distinguish by giving them water at the same hole after exposure to either odour.
This effectively dulled their sense of smell: the rats could not tell one smell from the other, even for a reward.
Their loss of discrimination was reflected in the piriform cortex, which now produced similar electrical patterns in response to both odours.
'Use it or lose it'
Lead researcher Prof Donald Wilson said: "We located where in the brain loss of smell may happen.
"And we showed that training can improve the sense of smell, and also make it worse.
"Our findings suggest that while olfactory impairment may reflect real damage to the sensory system, in some cases it may be a 'use it or lose it' phenomenon."
Andrew McCombe, honorary secretary of the British Association of Otorhinolaryngologists ENT-UK, said there was good evidence that keeping mentally active was good for brain function.
However, he said training our sense of smell was only likely to be helpful in its long-term preservation.
He said: "Loss of sense of smell is fortunately not too common but it is miserable when it happens as you usually lose your sense of taste - particularly flavour - to some extent too.
"Whilst interesting research, I am not sure it's going to suddenly lead to a significant change in the way we treat loss of sense of smell which sadly is usually permanent and complete when it happens."
11. Being bilingual 'boosts brain power'
Differences were seen in the brainstem (coloured orange in this picture)
Learning a second language can boost brain power, scientists believe. The US researchers from Northwestern University say bilingualism is a form of brain training - a mental "work out" that fine-tunes the mind. Speaking two languages profoundly affects the brain and changes how the nervous system responds to sound, lab tests revealed. Experts say the work in Proceedings of the National Academy of Sciences provides "biological" evidence of this.
For the study, the team monitored the brain responses of 48 healthy student volunteers - which included 23 who were bilingual - to different sounds. They used scalp electrodes to trace the pattern of brainwaves. Under quiet, laboratory conditions, both groups - the bilingual and the English-only-speaking students - responded similarly.
But against a backdrop of noisy chatter, the bilingual group were far superior at processing sounds. They were better able to tune in to the important information - the speaker's voice - and block out other distracting noises - the background chatter.
Powerful benefits
And these differences were visible in the brain. The bilingualists' brainstem responses were heightened.
Prof Nina Kraus, who led the research, said: "The bilingual's enhanced experience with sound results in an auditory system that is highly efficient, flexible and focused in its automatic sound processing, especially in challenging or novel listening conditions. "Co-author Viorica Marian said: "People do crossword puzzles and other activities to keep their minds sharp. But the advantages we've discovered in dual language speakers come automatically simply from knowing and using two languages. "It seems that the benefits of bilingualism are particularly powerful and broad, and include attention, inhibition and encoding of sound.
"Musicians appear to gain a similar benefit when rehearsing, say the researchers.
Past research has also suggested that being bilingual might help ward off dementia.
Learning a second language can boost brain power, scientists believe. The US researchers from Northwestern University say bilingualism is a form of brain training - a mental "work out" that fine-tunes the mind. Speaking two languages profoundly affects the brain and changes how the nervous system responds to sound, lab tests revealed. Experts say the work in Proceedings of the National Academy of Sciences provides "biological" evidence of this.
For the study, the team monitored the brain responses of 48 healthy student volunteers - which included 23 who were bilingual - to different sounds. They used scalp electrodes to trace the pattern of brainwaves. Under quiet, laboratory conditions, both groups - the bilingual and the English-only-speaking students - responded similarly.
But against a backdrop of noisy chatter, the bilingual group were far superior at processing sounds. They were better able to tune in to the important information - the speaker's voice - and block out other distracting noises - the background chatter.
Powerful benefits
And these differences were visible in the brain. The bilingualists' brainstem responses were heightened.
Prof Nina Kraus, who led the research, said: "The bilingual's enhanced experience with sound results in an auditory system that is highly efficient, flexible and focused in its automatic sound processing, especially in challenging or novel listening conditions. "Co-author Viorica Marian said: "People do crossword puzzles and other activities to keep their minds sharp. But the advantages we've discovered in dual language speakers come automatically simply from knowing and using two languages. "It seems that the benefits of bilingualism are particularly powerful and broad, and include attention, inhibition and encoding of sound.
"Musicians appear to gain a similar benefit when rehearsing, say the researchers.
Past research has also suggested that being bilingual might help ward off dementia.
12. Light-powered bionic eye invented to help restore sight
A retinal implant - or bionic eye - which is powered by light has been invented by scientists at Stanford University in California.
Implants currently used in patients need to be powered by a battery.
The new device, described in the journal Nature Photonics, uses a special pair of glasses to beam near infrared light into the eye.
This powers the implant and sends the information which could help a patient see.
Diseases such as age-related macular degeneration and retinal pigmentosa result in the death of cells which can detect light in the eye.
Eventually this leads to blindness.
Wiring eliminated
Retinal implants stimulate the nerves in the back of the eye, which has helped some patients to see.
Early results of a trial in the UK mean two men have gone from being totally blind to being able to perceive light and even some shapes.
However, as well as a fitting a chip behind the retina, a battery needs to be fitted behind the ear and a cable needs to join the two together.
The Stanford researchers say their method could be a step forward by "eliminating the need for complex electronics and wiring".
A retinal implant, which works in a similar way to a solar panel, is fitted in the back of the eye.
A pair of glasses fitted with a video camera records what is happening before a patient's eyes and fires beams of near infrared light on to the retinal chip.
This creates an electrical signal which is passed on to nerves.
Natural light is 1,000 times too weak to power the implant.
The researchers said: "Because the photovoltaic implant is thin and wireless, the surgical procedure is much simpler than in other retinal prosthetic approaches.
"Such a fully integrated wireless implant promises the restoration of useful vision to patients blinded by degenerative retinal diseases."
The implant has not been tested in people, but has been shown to work in rats.
Dr Keith Mathieson, now at the Institute of Photonics at the University of Strathclyde, was one of the lead researchers on the project. He said: "Age-related macular degeneration is a huge medical challenge and, with an aging population, is continuing to grow.
"This means that innovative, practical solutions are essential if sight is to be restored to people around the world with the condition.
"The implant is thin and wireless and so is easier to implant. Since it receives information on the visual scene through an infra-red beam projected through the eye, the device can take advantage of natural eye movements that play a crucial role in visual processing."
13. NHS 'should consider giving statins to healthy people'
Thousands of heart attacks and strokes could be prevented if the cholesterol-lowering drugs, statins, were more widely prescribed, research suggests.
The study of 175,000 patients, in the Lancet, said even very low-risk patients benefited from the medication.
The Oxford researchers says the NHS should consider giving statins to healthy people. The NHS drugs watchdog, NICE, is reviewing the evidence.
However, statins have been linked to side-effects such as kidney failure.
'Unparalleled' detail
They are among the most widely prescribed drugs in the UK and have long been known to help people at high risk of heart attack and stroke.
However, there has been considerable debate over medicating healthy people - both whether it works at all and if it would be socially acceptable.
Researchers at the University of Oxford say they have investigated the issue in "unparalleled" detail.
Their review of 27 trials concluded that statins significantly reduced the risk of heart attack and stroke for everyone.
Current rules from NICE - the National Institute for Health and Clinical Excellence - recommend statins for people who have a 20% or greater chance of developing cardiovascular disease within 10 years.
Doctors look at a patient's age, blood pressure, cholesterol levels and lifestyle to work out the risk.
One of the researchers, Prof Colin Baigent, told the BBC: "We've been taught over the years that high cholesterol is the thing that matters; you mustn't have high cholesterol.
"But what we've actually learned is that, whatever your level of cholesterol, reducing it further is beneficial.
"Whatever your level of risk, the benefits greatly exceed any known hazard."
He calculates that lowering the threshold for prescribing statins to a 10% risk of cardiovascular disease within a decade would lead to five million more people taking the drugs.
This in turn would save 2,000 lives and prevent 10,000 heart attacks or strokes every year, he said.
Prof Baigent said: "Half of [these] deaths come out of the blue in people who were previously healthy.
"If we are going to prevent that half of cardiac or stroke deaths, then we've got to consider treating healthy people.
"It can't be done any other way."
Caution urged
He, alongside fellow researchers, is now calling on NICE to review the evidence for giving statins to more people.
NICE, which sets drugs policy for England and Wales, said it was updating its guidelines.
The organisation said: "New evidence on statin treatment thresholds that has become available since publication of the original NICE guideline, including the study reported in the Lancet, will be considered as part of our review."
Their conclusions will be published towards the end of 2013.
One of the questions will be over side-effects. Statins have been linked to liver problems, kidney failure, muscle weakness and an increased risk of diabetes.
Prof Shah Ebrahim, from the London School of Hygiene and Tropical Medicine, conducted a large review of the evidence last year.
His results urged caution, and Prof Shah said doctors should stop prescribing to healthy patients.
He now says: "This research provides further evidence that statins are an effective and safe way of reducing the risk of heart attacks and strokes even among people at quite low risk of these conditions."
He suggests that universal prescribing to the over-50s might be appropriate, as 83% of 50-year old men have a 10% risk of cardiovascular disease in the next 10 years.
"The benefits of giving statins to everyone over the age of 50 would probably save the NHS money in the long run, owing to the savings in health care costs from the heart attacks and strokes prevented."
However, he questioned whether it would be good for people or society to resort to mass medication for lifestyle issues.
14. Male pill: gene discovery may lead to contraceptive
It may be possible to develop a new male contraceptive pill after researchers in Edinburgh identified a gene critical for the production of healthy sperm.
Experiments in mice found that the gene, Katnal1, was vital for the final stages of making sperm.The authors of a study in PLos Genetics said a drug which interrupts Katnal1 could be a reversible contraceptive.
A fertility expert said there was "certainly a need" for such a drug.
Contraception in men is largely down to condoms or a vasectomy.
Infertility search Researchers at the Centre for Reproductive Health at the University of Edinburgh were investigating the causes of male infertility.
They randomly altered the genetic code of mice to see which became infertile. They then traced the mutations which led to infertility, which led them to Katnal1.
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“Start Quote
Dr Lee SmithUniversity of EdinburghIf we can find a way to target this gene in the testes, we could potentially develop a non-hormonal contraceptive”
It contains the blueprints for a protein which is important in cells which support the development of sperm. Without the protein, sperm do not fully form and the body disposes of them.
Scientists hope they will be able to perform a similar trick in humans to stop sperm developing, without causing lasting damage.One of the researchers Dr Lee Smith said: "If we can find a way to target this gene in the testes, we could potentially develop a non-hormonal contraceptive.
"The important thing is that the effects of such a drug would be reversible because Katnal1 only affects sperm cells in the later stages of development, so it would not hinder the early stages of sperm production and the overall ability to produce sperm.
He said it would be "relatively difficult" to do as the protein lives inside cells, however, he said there was "potential" to find something else that protein worked with, which might be an easier target.
'Holy Grail' Dr Allan Pacey, senior lecturer in andrology at the University of Sheffield, said there was "certainly a need" for a non-hormonal contraceptive for men and that this had been a "Holy Grail" of research for many years.
He added: "The key in developing a non-hormonal contraceptive for men is that the molecular target needs to be very specific for either sperm or other cells in the testicle which are involved in sperm production.
"If they are not, then such a contraceptive could have unwanted side effects on other cells and tissues in the body and may even be dangerous.
"The gene described by the research group in Edinburgh sounds like an exciting new possible target for a new male contraceptive, but it may also shed light on why some men are sub-fertile and why their sperm does not work properly."
15. Premature birth linked to worse mental health
Being born prematurely is linked to an increased risk of a range of mental health problems much later in life, according to researchers.Bipolar disorder, depression and psychosis were all more likely, the study in The Archives of General Psychiatry suggested.
The overall risk remained very low, but was higher in premature babies.Experts cautioned there have since been significant advances in caring for premature babies.
Full-term pregnancies last for around 40 weeks, but one in 13 babies are born prematurely, before 36 weeks.
Heightened risk
Researchers at the Institute of Psychiatry at King's College London and the Karolinska Institute in Sweden analysed data from 1.3m people born in Sweden between 1973 and 1985.
They found 10,523 people were admitted to hospital with a psychiatric disorders, 580 of those had been born prematurely.
The academics showed full-term children had a two in 1,000 chance of being admitted. The risk was four in 1,000 for premature babies born before 36 weeks and six in 1,000 for those born before 32 weeks.
Very premature babies were more than seven times more like to have bipolar disorder and nearly three times as likely to have depression.
One of the researchers, Dr Chiara Nosarti, said the real figures may be higher as milder conditions would not have needed a hospital visit.However, she cautioned that the risk was low and the vast majority of premature babies are perfectly healthy.
She told the BBC: "I don't think parents should be worried, but we know that preterm birth confers an increased vulnerability to a variety of psychiatric conditions and perhaps parents should be aware of this and monitor early signs of later more serious problems."
She speculate that "disrupted development" may affect the babies' brains.
Striking
The chief executive of the mental health charity SANE, Marjorie Wallace, said: "We already knew that premature birth may be linked to schizophrenia, but to see evidence linking it to a range of psychiatric conditions which required hospitalisation is striking."
The baby care charity Bliss said it was well-established that early birth can affect the developing brain.
However, its chief executive Andy Cole cautioned that some of the people in the study were born "40 years ago and that neonatal clinical practice to limit neurological damage has been transformed over the past four decades, with significantly improved outcomes seen today."
There have been developments in cooling the brain to reduce any damage as well as improvements in ventilation to ensure enough oxygen is getting to brain.
16. Tomatoes are 'stroke preventers'
A diet rich in tomatoes may reduce the risk of having a stroke, according to researchers in Finland.
They were investigating the impact of lycopene - a bright red chemical found in tomatoes, peppers and water-melons.A study of 1,031 men, published in the journal Neurology, showed those with the most lycopene in their bloodstream were the least likely to have a stroke.
The Stroke Association called for more research into why lycopene seemed to have this effect.
The levels of lycopene in the blood were assessed at the beginning of the study, which then followed the men for the next 12 years.
They were split into four groups based on the amount of lycopene in their blood. There were 25 strokes in the 258 men in the low lycopene group and 11 strokes out of the 259 men in the high lycopene group.
The study said the risk of stroke was cut by 55% by having a diet rich in lycopene.
'Major reduction' Dr Jouni Karppi, from the University of Eastern Finland in Kuopio, said: "This study adds to the evidence that a diet high in fruits and vegetables is associated with a lower risk of stroke.
"The results support the recommendation that people get more than five servings of fruits and vegetables a day, which would likely lead to a major reduction in the number of strokes worldwide, according to previous research."
He said lycopene acted as an antioxidant, reduced inflammation and prevented blood clotting.
Dr Clare Walton, from the Stroke Association, said: "This study suggests that an antioxidant which is found in foods such as tomatoes, red peppers and water-melons could help to lower our stroke risk.
"However, this research should not deter people from eating other types of fruit and vegetables as they all have health benefits and remain an important part of a staple diet.
"More research is needed to help us understand why the particular antioxidant found in vegetables such as tomatoes could help keep our stroke risk down."
17. Drug 'may prevent stroke damage'
Clots block the flow of blood, starving the brain of oxygen
It may be possible to use a drug to prevent some of the lasting and crippling damage caused by a stroke, according to doctors in the US and Canada.
A safety trial, published in the Lancet Neurology medical journal, suggested the chemical NA-1 was safe to use. The study on 185 people also hinted that patients given the drug developed fewer regions of damaged brain tissue.
The Stroke Association said that it was promising, but needed more research.
Tests in primates had suggested NA-1 prevented brain cells dying when a stroke starved them of oxygen.
A small trial was set up at 14 hospitals in the US and Canada.
Patients who took part were having an operation to repair a brain aneurysm, a weakened blood vessel which could rupture, are at increased risk of a stroke.
Ninety-two people had the drug injected into a vein, while another 93 were injected with salty water.
'Safe' The doctors concluded that NA-1 was safe, with only two patients having mild side effects.
However, brain scans also showed that fewer brain lesions, damaged areas of tissue, formed in patients given the drug.
The doctors involved said the study provided evidence that "neuroprotection is achievable" but said that "a larger trial is necessary to investigate the robustness of the effect".
Prof Markku Kaste, from Helsinki University Central Hospital, said: "Age is the greatest risk factor for stroke. Because of the global population ageing, the number and burden of strokes will increase."
He said previous trials to use drugs to protect the brain had resulted in failure. His said this drug still need to be assessed in much larger clinical trials before its effectiveness was known.
Dr Peter Coleman, from the Stroke Association charity said: "We welcome any treatment that could protect brain cells after a stroke and limit the amount of brain damage. This potential treatment appears promising, but a lot more research is needed."
The trial was funded by the biopharmaceutical companies NoNO and Arbor Vita.
18. Closing hospital windows 'increases infection risk'
Keeping the windows open on traditional NHS wards can dramatically reduce the risk of infection, say researchers.
The University of Leeds study suggests closing windows, for example to cut heating bills, increases the risk of infection fourfold.The researchers used experiments and computer modelling to map the passage of air and germs through wards.
They say fitting household extractor fans to windows could maintain sufficient air flow in winter.
The researchers used computer modelling to trace air flows through open and partitioned wards Balloons filled with carbon dioxide - to represent an airborne pathogen - were popped and the gas followed throughout the ward using tracer devices.
Smoke sticks were also used to visually track the passage of air and wind streams.
The results showed that while the modern trend to partition wards to increase patient privacy changed the air-flow dynamics within a ward, good ventilation could be maintained if windows remained open.
"One of the biggest problems we have in the UK at the moment is that we don't have the money to just knock down every hospital and rebuild it," said Dr Cath Noakes, who led the study.
"We have to deal with what we've got, and many of the wards we've got are going to remain in use for a number of years to come.
"Our research was looking at these big naturally ventilated spaces to see what the risk of infection might be in there.
"What we found was that when the windows are open, these wards are very good.
"But if you close the windows and don't provide any alternative ventilation, the risks go up and they go up about fourfold.
"People are being told to seal up their buildings to save energy.
"We found, if you do that without alternative ventilation systems, you could be increasing the airborne infection risk significantly."
The researchers also looked at what could be done to maintain ventilation in winter months, when the windows had to be shut to keep patients warm.
"We actually used the little extractor fans - the type of thing you get in your bathroom at home.
"We installed those into the window and when we ran those, we found the risks became comparable to a naturally ventilated system."
Co-author Dr Miller Camargo-Valero said: "These simple, low-energy and low-cost solutions could also be of significant benefit for hospitals in the developing world, particularly in countries where airborne diseases such as tuberculosis are a major concern."
Funded by the Engineering and Physical Sciences Research Council, the study was published in the Building and Environment Journal.
Hermetic seals
While the research could help inform practices in older NHS buildings, many newer UK hospital buildings feature no opening windows and complex computer-controlled ventilation systems.
David Docherty, head of estates at the Royal London Hospital, part of Barts Health NHS Trust, told the BBC there were other considerations when it was decided to move the hospital from its old Whitechapel premises to a new adjacent building - namely, air pollution.
"Obviously, the air quality of London meant that we had to consider our patients first and we have to consider the quality of the air that's coming to them," he said.
Instead of opening windows, the new Royal London Hospital has 200 units that bring clean filtered air into the hospital's 3,500 rooms.
19. Nerve cells 're-grown' in rats after spinal injury
US scientists say they have made progress in repairing spinal cord injuries in paralysed rats.
Rats regained some bladder control after surgery to transplant nerve cells into the spinal cord, combined with injections of a cocktail of chemicals.
The study, published in the Journal of Neuroscience, could raise hopes for one day treating paralysed patients.
But UK experts say it will take several years of research before human clinical trials can be considered.
Scientists have tried for decades to use transplants of nerve cells to restore function in paralysed animals by bridging the gap in the broken spinal cord.
However, coaxing the cells to grow and form new connections has proved elusive.
One problem is the growth of scar tissue as the body's responds to injury, which seems to block cell regeneration.
Quote
Quote Dr Jerry Silver Case Western Reserve Medical School, Cleveland, Ohio"If we can show in a larger animal that our technique works and does no additional harm I see no reason why we couldn't move rapidly in humans”
US scientists carried out complex surgery to transplant nerves from the rodents' ribs into the gap in the middle of their spinal cord.
They also used a special "glue" that boosts cell growth together with a chemical that breaks down scar tissue in an attempt to encourage the nerve cells to regenerate and connect up.The researchers found for the first time that injured nerve cells could re-grow for "remarkably long distances" (about 2cm).
They said that while the rats did not regain the ability to walk, they did recover some bladder function.
Lead author Dr Jerry Silver of Case Western Reserve Medical School, Cleveland, Ohio, said: "Although animals did not regain the ability to walk, they did recover a remarkable measure of urinary control."
Co-author Dr Yu-Shang Lee of the Cleveland Clinic, Ohio, added: "This is the first time that significant bladder function has been restored via nerve regeneration after a devastating cord injury."
The findings may help future efforts to restore other functions lost after spinal cord injury.
They also raise hope that similar strategies could one day be used to restore bladder function in people with severe spinal cord injuries.
Dr Silver said further animal experiments will be needed to see if the technique could work in humans.
He told BBC News: "If we can show in a larger animal that our technique works and does no additional harm I see no reason why we couldn't move rapidly in humans."
'Remarkable advance'
Commenting on the study, Dr Elizabeth Bradbury of King's College London said several challenges must be overcome before the therapy can be trialled in patients.
"There are a number of challenges before this therapy can be brought to the clinic," she said.
"Nevertheless this is a remarkable advance which offers great hope for the future of restoring bladder function to spinal injured patients and if these challenges can be met we could be reaching clinical trials within three to five years."
Dr John Williams, head of neuroscience and mental health at the Wellcome Trust, said the implications for people are not yet clear.
"This is one of a number of ways that one can approach restoration of bladder function in paralysed patients, but careful studies will be needed to optimise which of the technologies under investigation might be of most benefit to patients."
20. Asthma genetic risk research could lead to future test
Research into the genetic risks for asthma could lead to a test which predicts which children will never grow out of it, says a study in The Lancet.
Scientists found that those at higher genetic risk of asthma were 36% more likely to develop serious, life-long asthma than those with lower risk.
But they said it was too soon to be used as a reliable clinical test.
Asthma UK says the findings could help identify people whose asthma could become severe.
Earlier studies had linked several genes to small increases in asthma risk.
This study, led by researchers from Duke University in North Carolina, identified 15 separate locations in the human genome which are associated with asthma.
Using this knowledge combined with data from a major New Zealand health study of more than 1,000 people since birth, the researchers were able to calculate the genetic risk score for 880 individuals.
They then tracked the development and progression of their asthma from early childhood through to their late 30s.
Those with higher genetic risk scores were more likely to have severe asthma which continued into adulthood, and they more often developed problems with lung function.But they said it was too soon to be used as a reliable clinical test.
Asthma UK says the findings could help identify people whose asthma could become severe.
Earlier studies had linked several genes to small increases in asthma risk.
This study, led by researchers from Duke University in North Carolina, identified 15 separate locations in the human genome which are associated with asthma.
Using this knowledge combined with data from a major New Zealand health study of more than 1,000 people since birth, the researchers were able to calculate the genetic risk score for 880 individuals.
They then tracked the development and progression of their asthma from early childhood through to their late 30s.
They were also more likely to miss school or work and to be admitted to hospital because of their asthma.
At present, there are no tests that can predict which children will recover as they grow older.
'Long way'
What is asthma?
Asthma affects the airways in the lungs and can cause a cough, wheezing and breathlessness.
It is one of the most common long-term medical conditions in the UK.
-
Dr Daniel Belsky, a post-doctoral fellow at the Duke Institute for Genome Sciences and Policy, said it was too early to talk about a predictive test for severe asthma.
"As additional risk genes are discovered, the value of genetic assessments is likely to improve."
He said there was still a long way to go before genetic risk scores could be used routinely in medical practice.
But the study could lead to a better understanding of asthma and how to treat it, he said.
Leanne Reynolds, from the charity Asthma UK, said it was misleading to assume that some children 'grow out' of the condition.
"We know that some children with asthma no longer experience symptoms when they reach adulthood, however... the underlying tendency still remains and so symptoms can still return in later life."
However, she said further research in this area would be welcomed.
"This could mean that in the future we're able to identify those people whose asthma will put them at greatest risk so we can ensure they get the support they need."
Genetic risk prediction for asthma is still in its infancy.”
End Quote Dr Daniel Belsky Duke University
21. 25 Horrible Things That Happen If You Don't Get Enough Sleep
In our 24/7 culture, sleep loss is a major problem. Back in 1942, we averaged almost 8 hours of sleep a night — now that's down to 6.8. (Seven to 9 hours per night are what's generally recommended.)
Almost 40% of Americans get less than 7 hours of sleep a night, a recent Gallup poll found, and an estimated 70 million Americans have a sleep disorder.
Everyone knows that it's important to get enough sleep — but you may not realize just how many things can go wrong when you don't.
Here are 25 unfortunate risks of partial and total sleep deprivation, some more common than others.
1. Irritability
"Complaints of irritability and [emotional] volatility following sleepless nights" are common, a team of Israeli researchers observed. They put those complaints to the test by following a group of underslept medical residents. The study found that the negative emotional effect of disruptive events — things like being interrupted while in the middle of doing something — were amplified by sleep loss.
Source: Sleep, 2005
2. Headaches
Scientists don't yet know exactly why sleep deprivation leads to headaches — but it's a connection doctors have noticed for more than a century. Migraines can be triggered by sleepless nights, and 36 to 58% of people with sleep apnea wake up with "nondescript morning headaches."
Source: Headache, 2003; Headache, 2005
3. Inability to learn
Sleepiness has long been an issue among adolescents. One study of middle school students found that "delaying school start times by one hour, from roughly 7:30 to 8:30, increases standardized test scores by at least 2 percentile points in math and 1 percentile point in reading."
But it's not just kids. Short-term memory is a crucial component of learning, and sleep deprivation significantly impaired the ability of adult volunteers to remember words they'd been shown the day before. In another study, researchers found that while people tend to improve on a task when they do it more than once, this isn't true if they are kept awake after they try it the first time — even if they sleep again before doing it again.
Source: Nature, 1999; Nature Neuroscience, 2000; Education Next, 2012
4. Weight gain
People who are underslept seem to have hormone imbalances that are tied to increased appetite, more cravings for high-calorie foods, a greater response to indulgent treats, and a dampened ability to control their impulses — a very dangerous combination. It's true that you burn more calories when awake, but not nearly enough to cancel out the many excess calories you consume when exhausted.
Source: Journal of Clinical Endocrinology & Metabolism, 2012; PLOS Medicine, 2004; Nature Communications, 2013; PNAS, 2013
5. Poor vision
Sleep deprivation is associated with tunnel vision, double vision, and dimness. The longer you are awake, the more visual errors you'll encounter, and the more likely you are to experience outright hallucinations.
Source: International Journal of Occupational Medicine and Environmental Health, 2010
6. Heart disease
When researchers kept people awake for 88 hours, their blood pressure went up — no big surprise there. But even subjects who were allowed to sleep for 4 hours a night had an elevated heart rate when compared to those getting 8 hours. Concentrations of C-reactive protein, a marker of heart disease risk, increased in those fully and partially deprived of sleep.
Source: Journal of the American College of Cardiology, 2004; PLOS ONE, 2009; Sleep Medicine Reviews, 2012
7. Slowness
Your reaction time is severely impeded when you don't get enough sleep. When researchers gave West Point cadets two tests that require quick decision-making, some were allowed to sleep between the tests, while others were not. Those who had slept did better the second time — those who had not did worse, and their reactions slowed down. A study in college athletes found similar results.
Source: Sleep, 2009; Asian Journal of Sports Medicine, 2012
8. Infection
You know that great thing your immune system does, where when you get an open wound of some kind it doesn't always get infected immediately? Prolonged sleep deprivation and even one night of sleeplessness can impede your body's natural defenses against microorganisms.
Source: American Journal of Physiology, 1993; The FASEB Journal, 1996
9. Economic risk-taking
Planning to make some changes to your portfolio? You might want to make sure you're well-rested. "A single night of sleep deprivation evoked a strategy shift during risky decision making such that healthy human volunteers moved from defending against losses to seeking increased gains," researchers concluded.
Source: The Journal of Neuroscience, 2011
10. Overproduction of urine
When people sleep, the body slows down its normal urine production. This is why most people don't have to pee in the night as much as they do during the day. But when someone is sleep deprived, this normal slowdown doesn't happen, leading to what researchers call "excess nocturnal urine production." This condition may be linked to bed wetting in children and, in adults, it's tied to what's called nocturia — the need to use the bathroom many times during the night.
Source: American Journal of Physiology, 2010; American Journal of Physiology, 2012
11. Distractedness
Having trouble paying attention to what you're reading or listening to? Struggling with anything that requires you to truly focus? "Attention tasks appear to be particularly sensitive to sleep loss," researchers have noted. If you want to stay alert and attentive, sleep is a requirement. Otherwise, you enter "an unstable state that fluctuates within seconds and that cannot be characterized as either fully awake or asleep," and your ability to pay attention is variable at best.
Source: Archives of Italian Biology, 2001; Seminars in Neurology, 2009
12. Less effective vaccines
Vaccines work by spurring your body to create antibodies against a specific virus. But when you don't sleep, your immune system is compromised, and this doesn't work quite as well. In one small study, 19 people were vaccinated against Hepatitis A. Ten of them got 8 hours of sleep the following night, while the rest pulled an all-nighter. Four weeks later, those who had slept normally had levels of Hepatitis A antibodies almost twice as high as those who'd been kept awake.
Another study found that a sleepless night did not have a long-term effect on immunity after a flu vaccine, it concludes that the effect might be specific to certain diseases. "Sleep should be considered an essential factor contributing to the success of vaccination," the Hep A researchers wrote.
Source: Psychosomatic Medicine, 2003; Journal of Immunology, 2011; BMC Immunology, 2012
13. Impaired speech
Severe sleep deprivation might make you sound like a bumbling idiot — much like having way too much to drink. "Volunteers kept awake for 36 hours showed a tendency to use word repetitions and clichés; they spoke monotonously, slowly, [and] indistinctly," one study noted. "They were not able to properly express and verbalize their thoughts."
Source: Sleep, 1997; International Journal of Occupational Medicine and Environmental Health, 2010
14. Colds
If you're wondering why you're sick all the time and seem to pick up every bug that travels around the office, it's probably because you're not getting enough sleep. When a group of 153 people were exposed to a common cold, those who had gotten less than 7 hours of sleep in the two weeks prior were almost 3 times more likely to get sick than those who'd had 8 or more hours of sleep. How well you sleep is also a factor – those who had spent 92% of their time in bed actually asleep were 5.5 times more likely to catch a cold than those who had been peacefully slumbering 98-100% of the time they were in bed.
Source: Archives of Internal Medicine, 2009
15. Gastrointestinal problems
One in 250 Americans suffer from Inflammatory Bowel Disease (IBD), and sleep deficiencies make its symptoms much worse. Regular sleep loss also makes you more likely to develop both IBD and inflammatory bowel syndrome, which affects an estimated 10-15% of people in the U.S. And patients with Crohn's disease were twice as likely to experience a relapse when they weren't getting enough sleep.
Source: World Journal of Gastroenterology, 2013
16. Car accidents
Drowsy driving is often compared to drunk driving: You really shouldn't do either. "Motor vehicle accidents related to fatigue, drowsy driving, and falling asleep at the wheel are particularly common, but often underestimated," one review concluded. Pilots, truck drivers, medical residents, and others required to stay awake for long periods of time "show an increased risk of crashes or near misses due to sleep deprivation."
Source: Seminars in Neurology, 2009
17. Depleted sex drive
Testosterone is an important component of sexual drive and desire in both women and men. Sleeping increases testosterone levels, while being awake decreases them. Sleep deprivation and disturbed sleep, consequently, are associated with reduced libido and sexual dysfunction, and people suffering from sleep apnea are at particular risk.
Source: American Journal of Obstetrics and Gynecology, 2007; Behavioral Brain Research, 2009; Journal of Sexual Medicine, 2009; Sleep Medicine, 2010; Brain Research, 2011
18. Pain
People in pain — especially those suffering from chronic pain — tend not to get enough sleep. This makes sense: Pain can wake you up in the night and make it hard to fall asleep in the first place. But recently, researchers have begun to suspect that sleep deprivation may actually cause pain or at least increase people's sensitivity to pain. One study found that after research subjects were kept awake all night, their pain threshold — the amount of painful stimulus they were able to endure — was lower.
Source: Journal of Sleep Research, 2001; Sleep Medicine Reviews, 2006
19. Diabetes
Being awake when your body wants you to be asleep messes with your metabolism, which in turn increases your risk for insulin resistance (often called "pre-diabetes") and type 2 diabetes. "Interventions to extend sleep duration may reduce diabetes risk," one study in adolescents concluded. And four large studies in adults found a strong association — though not a cause-effect relationship — between regular sleep loss and the risk of developing diabetes, even after controlling for other habits that might be relevant.
Source: Journal of Applied Physiology, 2005; Sleep, 2012; Annals of Internal Medicine, 2012
20. Sloppiness
Most people notice that when they're sleepy, they're not at the top of their game. One study found that one sleepless night contributed to a 20-32% increase in the number of errors made by surgeons. People playing sports that require precision — shooting, sailing, cycling, etc. — also make more mistakes when they've been awake for extended periods of time.
Source: The Lancet, 1998; Physiology & Behavior, 2007
21. Cancer
Scientists are just beginning to investigate the relationship between sleep and cancer, and different kinds of cancer behave differently. But since disrupted circadian rhythm and reduced immunity are direct results of sleep deprivation, it's no surprise that preliminary research seems to indicate that people who don't get enough sleep are at increased risk for developing certain kinds of cancer, most notably colon and breast cancers.
Source: Journal of the National Cancer Institute, 2003; Pathologie-biologie, 2003; Cancer, 2011; AAOHN Journal, 2011
22. Memory problems
Sleep disruptions in the elderly can lead to structural changes in the brain that are associated with impaired long-term memory — and sleep-related memory deficits have been observed in the general adult population as well. As early as 1924, researchers noticed that people who slept more forgot less. Poor sleep and not enough of it have also been linked to higher levels of β-Amyloid, a biomarker for Alzheimer's.
Source: Cell Signal, 2012; Nature Neuroscience, 2013; JAMA Neurology, 2013
23. Genetic disruption
A 2013 study shed some light on why sleep is tied to so many different aspects of our health and wellness. Poor sleep actually disrupts normal genetic activity. After one week of sleeping less than 6 hours per night, researchers found that more than 700 genes were not behaving normally, including some that help govern immune and stress responses.
Some genes that typically cycle according to a daily (circadian) pattern stopped doing so, while others that don't normally follow a daily pattern began doing so. What does this mean? Just one week of less-than-ideal sleep is enough to make some of your genetic activity go haywire.
Source: Proceedings of the National Academy of Sciences, 2013
24. Unhappiness and depression
In a classic study led by Nobel Prize-winning psychologist Daniel Kahneman, a group of 909 working women kept detailed logs of their moods and day-to-day activities. While differences in income up to $60,000 had little effect on happiness, a poor night's sleep was one of two factors that could ruin the following day's mood. (The other was tight deadlines at work.)
Another study reported higher marital happiness among women with more peaceful sleep, although it's hard to say whether happy people sleep better, better sleep makes people happier, or — most likely — some combination of the two. Insomniacs are also twice as likely to develop depression, and preliminary research suggests that treating sleep problems may successfully treat depressive symptoms.
Source: Science, 2004; Behavioral Sleep Medicine, 2009; Journal of Affective Disorders, 2011
25. Death
Many health problems are associated with sleep deprivation and poor sleep, but here's the big one: People who consistently do not get 7-8 hours of sleep are more likely to die during a given time period. Put more simply: We all die eventually, but sleeping too little — or even too much — is associated with a higher risk of dying sooner than you otherwise might.
Source: Sleep, 2010; Sleep Medicine Reviews, 2010
Miscarriage risk 'reduced by lifestyle changes'
More than a quarter of first-time miscarriages could be prevented by making a combination of lifestyle changes, research in Denmark suggests.
Researchers said lifting more than 20kg (44lbs) each day during pregnancy and being obese or underweight increased the risk of miscarriage.
Women beyond their early 30s, who drank alcohol and worked night shifts during pregnancy were also more likely to miscarry, they said.
The study analysed 91,427 women.
In the UK, more than one in seven pregnancies ends in miscarriage.
'Subject for prevention'
Researchers at the University of Copenhagen, which carried out the work, said only by reducing all of the risk factors could they be prevented.
The paper was published in the International Journal of Obstetrics and Gynaecology.
Anne-Marie Nybo Andersen, senior researcher at the University of Copenhagen, said: "The main message from the paper is that miscarriages are a subject for prevention."
Ms Nybo Andersen said the paper was significant as it showed the relative importance of different lifestyle factors in causing miscarriage, rather than more specific factors, such as certain pharmaceutical drugs.
As the findings were from the health perspective of a population, they could apply to lots of people - from individual couples to people in charge of maternity policies, work place regulations and supporting students who get pregnant, she said.
She added: "Everybody, young men and women, as well as those who have political responsibilities should bear in mind that postponing pregnancy to the mid-30s implies a seriously increased risk of miscarriage."
Healthy-pregnancy advice
Pregnancies included in the Danish National Birth Cohort between 1996 and 2002 were analysed for the study. Researchers found 3.5% of the women miscarried.
They looked for links between the miscarriages and lifestyle by collecting data through computer-assisted telephone interviews.
Caroline Overton, spokesperson at the Royal College of Obstetricians and Gynaecologists, said: "This is a very interesting study in terms of the very large population size."
She said it confirmed much of the advice currently given out in the UK to promote healthy pregnancy, such as not drinking, but questioned how applicable the study would be to British women.
On the subject of the findings, Ms Overton added: "Twenty kilograms is the size of a large holiday suitcase. Most of us would only lift that very occasionally."
Women wanting to conceive should also eat a balanced diet, make sure they are not "too skinny", or overweight, cut out smoking and ask their partners to follow suit, she said.
