Science and knowledge
New frog discovered in New York City
Why the 'Man in the Moon' faces Earth
Jilted fruit flies turn to alcohol
Fertilisers behind increase in N2O levels
Early Earth hazy one day, clear the next
Could air pollution be making us fat?
Frog skin protein may help fight superbugs
Electrotherapy dampens brain connections
Satellite images spot early settlements
Chemistry helps sperm find the right egg
Social butterflies find safety in numbers
Ibuprofen reduces altitude sickness: study
Mercury findings raise new questions
Megafauna collapse led to mega changes
New device invisible to magnetic fields
Travelling gnome answers weighty question
Study throws Moon theory up in the air
James Cameron reaches bottom of Pacific
Link builds between extremes and warming
Some chocolate-eaters have lower BMI
Dingoes, devils may be angels in disguise
Barefoot running less energy efficient
Dolphin males share human social network
Recycled spectacles twice that of new: study
Omega-3 pills may not help heart disease
Fish oil supplements of so-called omega-3 fatty acids may not do much to ward off heart attacks and strokes in people who already have heart disease, according to an international analysis.

The research, which appeared in the Archives of Internal Medicine and covered 14 studies, found that there was no difference in the number of heart attacks, strokes or deaths among more than 20,000 people with heart disease who were randomly assigned to take either fish oil supplement or fish oil free placebo pills.

Research has been mixed on the possible heart-related benefits of the omega-3 fatty acids, specifically those known as EPA and DHA, which can be taken as fish oil supplements as well as eaten. Groups such as the American Heart Association recommend at least two servings of such fish a week.

"There is a common perception that fish oil supplements have been proven to prevent cardiovascular disease, and in fact the evidence has been inconsistent and inconclusive," says JoAnn Manson, head of preventive medicine at Brigham and Women's Hospital in Boston, who co-wrote a commentary published with the study.

"It's an important issue, because a large percentage of the population is taking fish oil supplements over-the-counter," she says.
Meta-analysis of studies

Researchers from Korea combined the results of 14 studies that tracked heart disease patients taking fish oil or a placebo, without knowing which they were getting, for between one and five years. That included reports from the United States and India, as well as Italy, Germany and elsewhere in Europe.

The patients were mostly male and in their mid-60s, on average.

Those who were assigned to take the fish oil supplements were just as likely to have a range of heart-related emergencies, or to die, as study participants taking placebos containing vegetable oil or other substances not associated with heart health.

For example, in one study from the Netherlands, 14 per cent of people in either group had a stroke or heart attack, or needed a stent implanted, over about three and a half years.

There were also no differences in deaths or other heart and blood vessel problems when the researchers looked specifically at people taking higher or lower doses of fish oil, or among those who took the supplements for only a year or two or for longer, says Seung-Kwon Myung of the National Cancer Center in Ilsan, and colleagues.

Myung says he doesn't recommend that people, either with or without a history of heart disease, take the supplement to prevent future problems.
Longer-term studies needed

"At this point, we don't have enough hard-and-fast data to suggest routine supplementation with fish oil," says Alice Lichtenstein, a nutritional scientist at Tufts University in Boston, who wasn't involved in the study.

She notes that the studies in the review tended to only cover a couple of years on the supplements, and a heart attack or stroke can take much longer to develop.

Longer-term studies are needed on the impact of fish oil, says Manson. But for now people should continue to follow recommendations that advise at least two servings a week of fatty fish.

"Supplements will never be a replacement for a healthy dietary pattern, because often the healthier food choices such as fish can take the place of less-healthy food such as red meat," she added.

Для печати
Astronomers uncover stardust origins
Guns make people seem bigger
Traditional Chinese medicines under scrutiny
Baboons leave scientists spell-bound
Mars Viking robots 'found life'
Nothing helps create pure randomness
Jet lagged bees may help patient recovery
Study calls for regulating salt in fast foods
NASA clears SpaceX for space supply run
Egg size was dinos ultimate undoing
Peripheral vision snaps brain 'video' power
Study raises hopes of cure for baldness
Cosmic rays leave scientists in the dark
Bone-protecting protein discovered
Thylacine DNA reveals lacks of diversity
Aspirin's fat burning mechanism found
Polar bears are no new kids on the block
Calls back evolutionary gender theory
Asteroid impact pushes life underground
Arctic Ocean could be source of methane
Statins don't reduce melanoma risk
Facebook beauty is more than screen deep
Your brain could become your password
One hit of ecstasy 'resets body clock'
Antacid armour key to tetrapod survival
Fathers just as likely to get baby blues
Maths explains left-handed boxer success
Scientist claims to have found G-spot
Sprawling cities pressure environment
Fossil raindrops reveal early atmosphere
Fossil find reveals steps back in time
Report suggests new formula for Earth
Handprints may give away your height, gender
Monster solar tornadoes discovered
Study reveals why some soccer players dive
Teen brains undergo neural pruning
Martian dark spots reveal heart of glass
Cave holds earliest sign of fire-use
Stress may alter body's immune response
Japanese bees cook enemy in 'bee ball'
Tired locusts hold breath to rest their brains
X-rays shed new light on lung function
Mutant bird flu 'much less lethal'
T-rex had a giant feathered ancestor
Carbon dioxide ended last Ice Age: study
Saving ships from Titanic's fate
Dental x-rays linked to brain tumours
Fire-free farming in pre-Columbian Amazon
Teamwork made humans brainier: study
Drug data should be made public: report
Omega-3 pills may not help heart disease
Pigeons' sixth sense eludes scientists
Visit Statistics