Live longer and reduce death by heart disease significantly: Eat more fish

A longevity study has found that eating fatty fish and seafood -- rich in Omega-3 fatty acids -- can increase life expectancy and decrease mortality via heart disease.

A study conducted by Harvard School of Public Health (HSPH) and the University of Washington has found that, after reviewing the data derived from 2,700 older adults over a period of 16 years, those participants whose blood levels of Omega-3 fatty acids were high in fatty acids lived 2.2 years longer on average than did those with lower levels. Science Daily reported this week (April 1) that the study also discovered that, again on average, death by heart disease was reduced by about 35 percent among those with the higher fatty acid levels.

"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," said Dariush Mozaffarian, associate professor in the Department of Epidemiology at HSPH and lead author of the study. "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."

Other studies have held that fish could reduce the risk of death by heart disease. However, Mozaffarian's study hoped to clear up unclear areas concerning total mortality and death via various causes. The study hoped to find if the consumption of fish produced detectable blood biomarkers that would indicate possible causes of death.

The researchers analyzed the data for the proportion of fatty acids in participants' blood of three specific fatty acids and the cumulative levels of all three.

They found that docosahexaenoic acid, or DHA -- lowered the risk of coronary heart disease (CHD) death by 40 percent. This was especially true of CHD death due to arrhythmias, which saw a 45 percent lowered risk. Docosapentaenoic acid (DPA) was most strongly associated with lower risk of stroke death. Eicosapentaenoic acid (EPA) was most strongly linked with lower risk of nonfatal heart attack. At the same time, not one of the fatty acids were strongly related to other, noncardiovascular causes of death.

Taken in all, participants with higher levels of all three fatty acids were 27 percent more to reduce death via all the causes.

Findings also suggest that increasing fish and seafood in the diet from none to a medium intake of fish (about two servings per week) increased the levels of fatty acids significantly but tapered down to gradual increased levels thereafter.

The fatty acids study also built on earlier studies regarding fish, like the 2008 University of Kuopio (Finland) research that indicated that eating fish could lower the risk of stroke and the risk of cognitive decline in older people.

Still, the good news may be tempered by pre-existing conditions. According to Dr. Frank B. Hu and Dr. JoAnn E. Manson from the Harvard School of Public Health, increasing Omega-3 fatty acids intake via supplements when one already suffers from heart disease may have little to no effect on the progress of the disease. There was also no evidence to suggest that supplements strengthen or protect the heart. However, the researchers suggested their 2011 study may not have covered enough time. However, they suggested that eating actual fatty fish could possibly make a greater long-term difference, something Mozaffarian's more recent research seems to support.

(photo credit: Lucarelli, Creative Commons)