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Eating fish no help for heart? What new study says

fish oil capsules
Some doctors seem to think that fish oil capsules help lower levels of LDL (bad) cholesterol. Dr. Richman says they don't - though they can help lower levels of fatty substances known as triglycerides, which also play a role in heart disease. istockphoto

(CBS) Is there something fishy about the scientific evidence that suggests eating fish and fish oil helps prevent heart disease? A new study shows that the risk of developing heart disease is just as high in people who eat lots of the omega-3 fatty acids found in fish and fish oil as it is in people who eat less of the stuff.

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At least that was the case among men. The study showed that women who eat lots of omega-3's are significantly less likely to develop heart disease.

The study, published in the October issue of the American Journal of Clinical Nutrition, seems to throw cold water on the conventional wisdom about fish and heart disease.

In 2004, the FDA said there was evidence that consuming omega-3 fatty acids can reduce the risk for heart disease, according to Reuters.

In light of such evidence, the American Heart Association recommends eating at least two weekly servings of fish (and possibly taking fish oil supplements), saying that the acids can lower triglycerides and blood pressure and slow the growth of fatty plaques in coronary arteries - all factors that have been linked to heart disease. One NIH website says that "some investigators believe that fish oil may be even more effective in reducing death from heart attacks than a group of commonly used cholesterol-lowering drugs called "statins."

For the study, researchers in Denmark tracked the health and dietary habits of 3,277 Danish men and women who were known to be free of heart disease at the study's beginning. During more than two decades of follow-up, there were 471 cases of ischemic heart disease (the form caused by the buildup of fatty plaques within the coronary arteries). Consumption of omega-3's had no effect on men's heart risk. Among women, those who consumed the most omega-3's were about 40 percent less likely to develop heart disease than women who consumed the least.

What does it all mean?

Dr. Penny M. Kris-Etherton, distinguished professor of nutrition at Penn State University, expressed doubts about the study's findings. She told CBS news that the study may have included too few people to have yielded reliable data, adding that clinical trials involving more than 100,000 people had demonstrated clear benefits to the heart from eating fish.

What advice does she have for people who have been eating fish or fish oil (or omega-3 fortiified foods)? "Continue to do that," she said. "Everybody should be eating fish."

In other words, when it comes to heart-healthy eating, the study doesn't mean you're off the hook.

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