Japan's Heart-Healthy Diet: Fish Is Key
Study Shows High Omega-3 Levels in Japanese Diet Cuts Heart Disease Rates
High Omega-3 Levels continued...
He adds that the average omega-3 intake in Japan of 1 gram a day is about eight times higher than the amount the typical American gets.
"We are not a nation that loves fish, and that isn't likely to change," he says. "But it is increasingly clear that we need to get more omega-3 into our diets."
Fish oil supplements are one way of doing this. Studies in individuals with heart disease have shown a benefit of supplemental omega-3 fatty acids. Based on these studies, the American Heart Association recommends that people with heart disease take 1 gram of EPA plus DHA daily.
Other good sources of omega-3 include foods such as flaxseed and canola oils, soybean, tofu, and walnuts. Omega-3 fatty acids are often sold as capsules but can upset the stomach and should be taken with food.
Harris is working to develop a soybean-based omega-3-enriched oil through a grant from the company Monsanto.
He believes that many of the foods we eat will soon be fortified with omega-3 in the same way that they are now fortified with folic acid and other vitamins.
"Either we get people in the U.S. to start liking oily fish, which probably isn't going to happen, or we find another way of getting it into our food," he says.
Fish Eaters Had Less Plaque
The study by Sekikawa and colleagues included 281 Japanese men living in Japan, an equal number of Japanese men living in the U.S., and 306 white men who lived in the U.S.
All the men were in their 40s, and all underwent blood testing to determine serum levels of fatty acids, including omega-3. The men also had two tests for atherosclerosis -- one measuring the thickness of the artery wall in a major neck artery that sends blood to the brain and the other measuring plaque in arteries leading to the heart.
While total fatty acid levels were similar in the three groups, blood omega-3 levels in the Japanese men living in Japan were 45% higher and 80% higher, respectively, than in Japanese men and white men living in the U.S.
And both measures of artherosclerosis showed less plaque buildup in the arteries of the Japanese men living in Japan. Atherosclerosis levels were similar in both Japanese-Americans and in white Americans.
The study appears in the Aug. 5 issue of the Journal of theAmerican College of Cardiology.
"This indicates that much lower death rates from coronary heart disease in the Japanese in Japan is very unlikely due to genetic factors," Sekikawa says.