Omega-3 fatty acids from fish help reduce coronary artery calcification promoting a healthier heart, a new study finds.

Japanese men eat ten times more fish than American men. This probably explains why Japanese men are three times less likely to suffer from coronary artery calcification, which is the hardening of arteries in the body. This condition increases the risk of heart attacks, strokes and other cardiovascular diseases.

University of Pittsburgh Graduate School of Public Health researchers found that omega-3 fatty acids sourced from fish help to reduce coronary artery calcifications. For the study, researchers examined 300 men over the course of five years. During this time, they tracked factors affecting cardiovascular health such as cigarette smoking, alcohol consumption, high blood pressure, diabetes rate and cholesterol in the blood. One of the findings revealed that American men had three times the incidence of coronary artery calcification compared to the Japanese men.

"Multiple studies have looked at the effect of fish oil on cardiovascular health, with mixed results," said lead author Akira Sekikawa, M.D., Ph.D., associate professor of epidemiology at Pitt Public Health in a statement. "Previous studies investigated substantially lower intake of omega-3 fatty acids than what people in Japan actually get through their diet. Our study seems to indicate that the level of marine-derived omega-3 fatty acids consumed must be higher than previously thought to impart substantial protection."

Researchers also found that the levels of fish-derived omega-3 fatty acid in the blood of Japanese men were more than 100 percent higher than in white men. Researchers noted that omega 3 fatty acids, derived especially from oily fish like squid and krill, help to reduce inflammation and slow the formation of fatty plaques in arteries.

"The vast difference in heart disease and levels of marine-derived omega-3 fatty acid are not due to genetic factors," said Dr. Sekikawa, according to NY Times. "When we look at Japanese Americans, we find that their levels of coronary artery calcification are actually higher than that of the rest of the U.S. population."

The average dietary intake of fish by Japanese people living in Japan is nearly 100 grams each day, which the American Heart Association considers to be 1.5 servings. According to Daily Mail, the average American man eats approximately seven to 13 grams of fish daily, which accounts to about one serving a week.  

"I am not encouraging Americans to start consuming massive amounts of fish, which may have harmful contaminants, such as mercury, in their flesh," authors of the study said. "However, our findings indicate that it is worthwhile to take another look at the effect of marine-derived omega-3 fatty acids on heart disease, particularly when consumed at higher rates than previously investigated."

This study follows another study conducted by Uppsala University researchers who found that people who eat a lot of fish are less likely to develop a "muffin top", the Daily Mail reported.

The study was funded by grants from the Japanese Ministry of Education Culture, Sports, Science and Technology and National Institutes of Health (NIH). Findings were published online in the journal Heart.