The researchers analyzed the total proportion of blood omega-3 fatty acids, including three specific ones, in participants' blood samples at baseline. After adjusting for demographic, cardiovascular, lifestyle, and dietary factors, they found that the three fatty acidsboth individually and combinedwere associated with a significantly lower risk of mortality. One type in particulardocosahexaenoic acid, or DHAwas most strongly related to lower risk of coronary heart disease (CHD) death (40% lower risk), especially CHD death due to arrhythmias (electrical disturbances of the heart rhythm) (45% lower risk). Of the other blood fatty acids measuredeicosapentaenoic acid (EPA) and docosapentaenoic acid (DPA)DPA was most strongly associated with lower risk of stroke death, and EPA most strongly linked with lower risk of nonfatal heart attack. None of these fatty acids were strongly related to other, noncardiovascular causes of death.
Overall, study participants with the highest levels of all three types of fatty acids had a 27% lower risk of total mortality due to all causes.
When the researchers looked at how dietary intake of omega-3 fatty acids related to blood levels, the steepest rise in blood levels occurred when going from very low intake to about 400 mg per day; blood levels rose much more gradually thereafter. "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," said Mozaffarian.
|Contact: Marge Dwyer|
Harvard School of Public Health