|now they tell them-lol|
March 24, 2006]
Omega 3 might not be the lifesaver you thought it was
(Western Mail Via Thomson Dialog NewsEdge)Scientists have cast doubt on whether fish oils can really help protect against heart disease. Research published today suggests that omega 3 essential fats, which are found in oily fish, may not be as beneficial as thought. Current food guidance advises that everyone should eat two portions of fish a week - one of which is oily - to obtain optimum levels of omega 3. And supplements containing the essential fatty acids are among some of the best-selling, as consumers increasingly reach for a daily pill in the hope of protecting themselves against future disease. But the research published on BMJ online said there was little evidence to support the findings that omega 3 can protect against heart disease or even prevent a second heart attack. Despite the findings, leading dieticians said the public should not stop eating oily fish as omega 3 is associated with a huge range of health benefits. Lee Hooper, a lecturer at the University of East Anglia's School of Medicine, said the evidence from 89 studies into omega 3 showed no strong evidence of its beneficial effects on cardiovascular disease or mortality. She said when the results of studies on long-chain omega 3 fats were analysed separately, total mortality and cardiovascular events were not reduced.
And she said that no study showed increased risk of cancer or stroke with higher intake of omega 3, but there were too few events to rule out important effects.
But she said, 'UK guidelines advising people to eat more oily fish should continue at present but the evidence should be reviewed regularly.
'However, it is probably not appropriate to recommend a high intake of omega 3 fats for people who have angina but have not had a heart attack.'
Omega 3 is thought to have several effects on individual factors, such as blood pressure, which contribute to heart disease.
Research involving the Caerphilly men study, one of the studies the new review looked at, revealed the link between omega 3 and a 30% reduction in the number of secondary heart attacks suffered by people who had already had one heart attack. But when the study was repeated the results did not confirm that finding.
Despite current advice about eating oily fish, only about a third of the population eat one serving a week, while the remainder eat none.
Ursula Arens, a registered dietician and spokeswoman for the British Dietetic Association, said there would have to be a three-fold increase in oily fish consumption to meet current guidelines.
She said, 'We should definitely carry on with the advice to eat one serving of oily fish a week - I don't think this is in any way unhealthy.
'There is lots of evidence about the positive effects of omega 3 and these findings should not be a prompt for us to stop eating it.'
Dr Mike Knapton, director of prevention and care for the British Heart Foundation, said, 'People should not stop consuming omega 3 fats or eating oily fish as a result of this study. Until now, medical research has demonstrated a benefit from omega 3 fats in protecting people from heart and circulatory disease.
'This systematic review of numerous studies concludes that there is no clear evidence either way.
'More research is needed to establish why some studies have shown a slightly increased risk associated with eating very high amounts of oily fish, which is possibly related to mercury levels.
'However, whatever amount of oily fish you consume, the impact on your risk of heart disease is negligible compared to the benefits of quitting smoking, doing regular exercise and eating a diet low in saturated fats.': Fatty acids that do a world of good:Omega 3 is the name given to a family of polyunsaturated fatty acids. Although described as essential, from the point of view of human nutrition, the long-chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are considered much more valuable as these are the forms the body requires.
Omega 3 fats provide the body with energy, but they also have important health roles. Research has suggested they help an unborn baby's brain to develop, and studies have found that children who regularly ate oily fish had a four times lower risk of developing asthma than children who rarely ate such fish. Other research has found fish oil to be beneficial in the treatment of other lung diseases such as cystic fibrosis. Omega 3 has also been found to have beneficial effects on osteoarthritis and eyesight in later life. It even reduces the risk of the lung disease chronic obstructive pulmonary disease in smokers.
JUST IN TIME-VBG-
March 27, 2006
Pork That's Good for the Heart May Be Possible With Cloning
By GINA KOLATA
A group of university researchers said yesterday that they had created what sounds like a nutritional holy grail: cloned pigs that make their own omega-3 fatty acids, potentially leading to bacon and pork chops that might help your heart.
For now, the benefits of the research are theoretical. Omega-3 fatty acids, which have been linked to a lowered incidence of heart disease, are primarily found in fish. No one knows whether they would have the same effect if eaten in pork.
And government approval for such genetically modified foods is certain to face monumental opposition from some consumer groups. Some already object to feeding farm animals genetically modified grain, and genetically modifying the animals themselves and cloning them would be "a double whammy," said Joseph Mendelson, the legal director for the Center for Food Safety, a nonprofit group that opposes the use of genetically engineered products. "I am confident that consumers would not want them."
Still, some scientists say the findings, published online by the journal Nature Biotechnology, are an important forerunner of things to come. Although close to a dozen animals have been cloned in the decade since Dolly the sheep, using cloning to change the nutritional value of farm animals is groundbreaking.
"At this point, it's a new era," said Alice H. Lichtenstein, a professor of nutrition science and policy at the Gerald J. and Dorothy R. Friedman School of Nutrition Science and Policy at Tufts University School of Medicine.
Alexander Leaf, an emeritus professor of clinical medicine at Harvard, said he was confident that pork and other foods with omega-3's would eventually get to American consumers and that they would be better for it.
"People can continue to eat their junk food," Dr. Leaf said. "You won't have to change your diet, but you will be getting what you need."
For years, people have been urged to eat fish rich in omega-3 fatty acids. But fish can be expensive, not everyone likes it, and omega-3's are in greatest abundance in oily fish like tuna, which contains mercury.
That nutritional conundrum led a group of scientists from Harvard Medical School, the University of Missouri and the University of Pittsburgh Medical Center to think of modifying pigs.
What resulted was five white piglets with muscle tissue larded with omega-3 fatty acids. They live at the University of Missouri in individual pens with fiberglass-railed sides, concrete floors and black foam pads for beds.
Pigs with their own omega-3 fatty acids exist in nature, notably a Spanish breed called Ibérico. But Dr. Jing X. Kang, an associate professor of medicine at Harvard Medical School and the lead author of the new paper, said pigs were only the beginning, adding that he was also developing cows that made omega-3's in their milk and chickens that had the fatty acids in their eggs.
It will be years before such products make their way to market, if ever. Michael Herndon, a spokesman for the Food and Drug Administration, said in an e-mail message that research with genetically engineered animals would probably require approval from the agency and that the F.D.A. "also expects documentation of plans regarding the disposition of all investigational animals after their participation in the study is completed."
Mr. Herndon said the F.D.A. had not yet approved any genetically modified animals for food.
Mr. Mendelson of the Center for Food Safety added that his group worried about the ability of the food and drug agency to determine the safety of genetically modified foods. And he said the cloning process could produce unhealthy animals.
For those who do not object to genetically modified or cloned animals, the question is whether eating such altered foods will make a difference in health. And on that, "all bets are off," said Dr. Lichtenstein of Tufts.
Many questions remain, she said: How important are omega-3 fatty acids to human health? Would getting the fatty acids in meat be the same as getting them in fish? And is it really such a good idea to put omega-3's into foods like pork that contain saturated fats and cholesterol, which could increase risk of heart disease?
Dr. Kang said the work began a few years ago when he put a gene for the production of omega-3 fatty acids into mice. Mammals do not have that gene; it is found instead in microorganisms, plankton, algae and worms, he said. Fish get the fatty acids by eating algae.
Dr. Kang used a gene from roundworms that converts an abundant form of fatty acid, omega-6, to omega-3. He had to modify the worm enzyme, making it into one that would function in mammals.
Then he injected the gene for the enzyme into mouse embryos, some of which took it up, yielding mice that made their own omega-3's. (In a paper that is being readied for publication, he says these mice are protected from a variety of chronic illnesses, presumably because they make the fatty acids.)
The next step was to create pigs with the enzyme. That work was done by Randall S. Prather, a pig cloning expert at the University of Missouri, who used genetically modified pig cells to create the five cloned pigs that had the gene in every cell of their bodies and made their own omega-3 fatty acids in their muscles.
Although pigs have been cloned before — along with a growing list of animals, including sheep, mice, rats, cows, goats, rabbits, cats, a mule, a horse and a dog — these are the first livestock to be cloned and genetically modified to make omega-3's.
Dr. Prather said the omega-3 pigs, born in November, will be bred when they reach puberty. Then, he said, "we will distribute them to researchers who are interested."
Pigs are often used to study heart disease, and the cloned pigs offer a new opportunity, Dr. Prather said. Instead of comparing human populations who happen to eat, or not eat, foods with abundant omega-3, scientists can ask their question directly: Compared with pigs without the omega-3 fatty acids, do these cloned pigs have a reduced heart attack risk, or don't they?