Fish-rich Diet Lowers Heart Risk

A seafood-rich diet typically served in Japan could help you protect against heart disease, a new study published in the August 5, 2008 issue of the Journal of the American College of Cardiologydefine suggests.

Despite the fact that Japanese smoke much more than Americans, they are still far less likely to have dangerous plaque build-up in their blood vessels, and this is all because of their habit of eating diet loaded with omega-3 fatty acids from fish.

"Japanese living in Japan eat fish every day, about 100 grams every day," said study author Dr. Akira Sekikawa, an assistant professor of epidemiology at the Graduate School of Public Health at the University of Pittsburgh in Pennsylvania. "They also have very low rates of coronary heart disease, even with a high rate of smoking and other risk factors."

Sekikawa and colleagues reach their conclusion after studying 281 Japanese men from Kusatsu, Shiga, Japan, 306 white American men from Allegheny County, Pennsylvania; and 281 Japanese-American men from Honolulu, Hawaii, all between the ages of 40 and 49.

The researchers found that the total level of fatty acids was similar in the three groups, but the Japanese men had two times higher levels of omega-3 fatty acids (9.2%) than white Americans (3.9%) or Japanese Americans (4.8%). The Japanese men also had the lowest levels of atherosclerosis than their counterparts.

Overall, the researchers found that the Japanese men living in Japan though had far higher rates (47%) of smoking, one of the most significant heart disease risk factors, but they still had remarkably less coronary arterydefine calcifications and less build-up in their carotid arteriesdefine.

On contrary, Japanese-American men had the highest number of heart disease risk factors of all three groups, like the highest average body-mass index, blood pressure, triglycerides and the highest levels of diabetes.

"The death rate from coronary heart disease in Japan has always been puzzlingly low," said Sekikawa. "Our study suggests that the very low rates of coronary heart disease among Japanese living in Japan may be due to their lifelong high consumption of fish."

The study concludes that very high levels of omega-3 fatty acids have strong properties that may help prevent the buildup of cholesterol in the arteries

Japanese men consume an average of 100 grams, equivalent to about 3.75 ounces, of fish every day from early in life, while typical Americans eat oily fish, such as salmon or albacore tuna, less than two times a week.

Omega-3 fatty acids are a type of polyunsaturated fat found primarily in fish. The two most potent omega-3 fatty acids are known as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) and are usually found in oily fishes, such as mackerel, salmon and tuna.

Although the findings determine a link between higher intake of marine-derived omega-3 fatty acids and the lower intima-media thickness and coronary artery calcification, but the researchers said further research is also needed to test whether long-term, mega-dose omega-3 fatty acid could minimize coronary heart disease rates.