Consumption of fish oil may help ward off heart diseases, says new study.
According to the study, led by the University of Pittsburgh Graduate School of Public Health, middle-aged men in Japan had lower incidence of coronary artery calcification, a predictor of heart disease, than middle-aged white men living in the US, likely due to the significantly higher consumption of omega-3 fatty acids found in fish.
Lead author Akira Sekikawa, associate professor of epidemiology at Pitt Public Health, said that 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," she said.
Marine-derived omega-3 fatty acids, which are found in fish, especially oily fish, as well as in squid and krill, may help to reduce inflammation and slow the formation of fatty plaques in arteries.
Researchers at Pitt partnered with scientists in Japan, Hawaii and Philadelphia to follow nearly 300 men for five years, tracking multiple factors that affect cardiovascular health, including cigarette smoking, the level of cholesterol in the blood and alcohol consumption, as well as their rates of diabetes and high blood pressure.
After accounting for risk factors for heart disease, the U.S. men had three times the incidence of coronary artery calcification as the Japanese men.
Meanwhile, the levels of marine-derived omega-3 fatty acid in the blood were more than 100 percent higher in the Japanese than in the white men.
The vast difference in heart disease and levels of marine-derived omega-3 fatty acid are not due to genetic factors, Sekikawa said.
The average dietary intake of fish by Japanese people living in Japan is nearly 100 grams each day, which the American Heart Association considers 1 1/2 servings.
The average American eats about 7 to 13 grams of fish a day, or about one serving a week.
The study is published in the journal Heart.