Lead author Dariush Mozaffarian of the Harvard School of Public Health and colleagues at the University of Washington also found seniors with the highest level of omega-3 fatty acids lower their risk of dying by 2.2 years and reduce their risk of heart disease by about 35 percent.
"Although eating fish has long been considered part of a healthy diet, few studies have assessed blood omega-3 levels and total deaths in older adults," Mozaffarian said in a statement. "Our findings support the importance of adequate blood omega-3 levels for cardiovascular health, and suggest that later in life these benefits could actually extend the years of remaining life."
The research teams examined 16 years of data from about 2,700 U.S. adults age 65 or older who participated in the Cardiovascular Health Study, a long-term study supported by the National Heart, Lung, and Blood Institute.
At the beginning of the study and regularly during follow-up, participants had blood drawn, underwent physical examinations and diagnostic testing, and were questioned about their health status, medical history and lifestyle.
The study, published in the Annals of Internal Medicine, found after adjusting for demographic, cardiovascular, lifestyle and dietary factors, the study found the three fatty acids -- docosahexaenoic acid, or DHA, eicosapentaenoic acid, or EPA, and docosapentaenoic acid, or DPA -- were most strongly associated with lower risk of stroke death.
"The findings suggest that the biggest bang-for-your-buck is for going from no intake to modest intake, or about two servings of fatty fish per week," Mozaffarian said.