Fishing for ways to protect your heart? The first international study is out that compares omega-3 levels in Japan and the west.

The August 5, 2008 issue of the Journal of the American College of Cardiology (JACC) reports that Omega-3 fatty acids from fatty or oily fish appear to prevent clogged arteries, even in middle aged men with risk factors.

This new research indicates a seafood rich diet high in tuna, sardines, salmon, and other fatty fish appears to protect against clogged arteries regardless of other cardiovascular risk factors. In the article, it is reported that Japanese men, living in Japan, on average had twice the blood levels of omega-3 fatty acids. This finding was independently linked to low levels of atherosclerosis.

Akira Sekikawa, M.D., PhD, an assistant professor of epidemiology at the University of Pittsburgh, PA, and an adjunct associate professor at Shiga University of Medical Science, Otsu, Japan stated, “The death rate from coronary heart disease in Japan has always been puzzlingly low” and ”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.”

An earlier study by Dr. Sekikawa’s team reported that Japanese men had less cholesterol build up in their arteries as compared to white men living the in the US, regardless of similar blood cholesterol levels and blood pressure readings, and similar rates of diabetes. Very surprising was the fact that rates of cholesterol buildup were less even though Japanese men have a much higher incidence of cigarette smoking! In previous studies it was not clear whether the low levels of clogged arteries was due to strong genes, increased consumption of fish, or some other factor.

To determine the answer to that question, the ERA JUMP Study (Electron-Beam Tomography, Risk Factor Assessment Among Japanese and U.S. Men in the Post-World War II Birth Cohort) signed up 868 randomly selected men from ages 40-49. Study participants were examined and had blood work to evaluate cardiovascular health. Lab tests measured the blood levels of fatty acids and the omega-3 fatty acids that come from fish (EPA, DHA, DPA).

Ultrasounds and EB-CT scans were also used to measure cholesterol buildup and intimal-medial thickness and calcification (calcium deposits, coronary arterial calcification (CAC)), respectively.

The study found that total levels of fatty acids were similar across the represented groups, however the percentage of fish based omega-3 fatty acids was two-fold higher in Japanese men living in Japan (9.2%) when compared to white men (3.9%) and Japanese-American men (4.8%) residing in the US.

The data from the study showed significant correlation between the percent of omega-3 fatty acids in the blood and intimal media thickness of arteries, incidence of atherosclerosis, and overall cardiovascular risk in Japanese men, living in Japan. Also, it was shown that coronary arterial calcification (CAC) went down as omega-3 fatty acids levels went up, but the relationship was not statistically significant.

“Our study clearly demonstrated that whites and Japanese-Americans have similar levels of atherosclerosis, which are much higher than in the Japanese in Japan,” Dr. Sekikawa said. “This indicates that much lower death rates from coronary heart disease in the Japanese in Japan is very unlikely due to genetic factors.”(1)

This article is the latest in a plurality of reports that underscore the importance of fish-derived omega-3 fatty acids in reducing the risk for heart disease. Science Daily (2) reported comments from William W. Harris, Ph.D. and senior scientist and director of the Metabolism and Nutrition Research Center, Sanford Research/University of South Dakota, Sioux Falls. “Japanese men in Japan have equally bad or worse cardiovascular risk profiles as Americans, but less heart disease. How can this be?” said Dr. Harris, who was not involved in the ERA JUMP study. “What really distinguishes the Japanese men from the Americans is the fact that blood levels of the omega-3 fatty acids are twice as high in Japan as they are in the West.”

Article written by Jim Mosbaugh, Vice President with PanGenex Corporation. Visit www.PanGenex.com for more information.

1. Sekikawa et al. Marine-Derived n-3 Fatty Acids and Atherosclerosis in Japanese, Japanese-American, and White Men: A Cross-Sectional Study. J Am Coll Cardiol, 2008 52: 417-424 DOI: 10.1016/j.jacc.2008.03.047
2. Japanese Diet Rich In Fish May Hold Secret To Healthy Heart: Omega-3 Fatty Acids From Fish Appear To Prevent Clogged Arteries ScienceDaily (July 29, 2008)