High omega-3 fatty acid levels may lower risk of death

Older adults who have higher blood levels of omega-3 fatty acids may be able to lower their overall mortality risk by up to 27% and their mortality risk from heart disease by about 35%, says a new US study.

The observational study analyzed blood omega-3 fatty acid concentrations of 2,692 healthy adults with an average age of 74 along with cases of death and incidents of fatal or nonfatal coronary heart disease (CHD) as well as stroke over a period of16 years (1). The results showed that – after adjusting for demographic, cardiovascular, lifestyle, and dietary factors – increased blood concentrations of three fatty acids, both individually and combined, were associated with a significantly lower risk of mortality: in particular docosa-hexaenoic acid (DHA) was most strongly related to lower risk of CHD-related death (40% lower risk), especially CHD death due to disturbances of the heart rhythm (45% lower risk). Increased blood levels of eicosapentaenoic acid (EPA) and docosapentaenoic acid (DPA) were most strongly associated with lower risk of death due to stroke, and EPA was most strongly linked with lower risk of nonfatal heart attack. Study participants with the highest levels of all three types of fatty acids had a 27% lower risk of all-cause mortality overall. The steepest rise in blood omega-3 fatty acid levels occurred when participants went from very low intake to a modest intake of about 400 mg per day or about two servings of fatty fish per week.

The researchers concluded that participants who had the highest blood levels of omega-3 fatty acids lived, on average, 2.2 years longer than those with lower levels. The findings would thus support the importance of adequate blood levels for cardiovascular health, and suggest that later in life these benefits could actually extend the years of remaining life. Previous studies have found that increased intakes of fish, which is rich in omega-3 fatty acids, may reduce the risk heart disease-related death. However, the effect on other causes of death or on total mortality remains unclear.

1. Mozaffarian D. et al. Plasma phospholipid long-chain omega-3 fatty acids and total and cause-specific mortality in older adults: a cohort study. Ann Intern Med. 2013; 158(7):515–525.