According to a large-scale analysis published in the journal Nature Communications, having a higher omega-3 index (blood concentrations of EPA and DHA) is associated with overall increased life expectancy, compared to participants who had low levels of circulating omega-3 fatty acids. With all else being equal, those with low omega-3 fatty acid levels might have lived past their premature deaths, the authors of the study, who were from FORCE (Fatty Acids and Outcomes Research Consortium), said.
 
While a wide range of studies have examined the link between omega-3s and specific diseases affecting the heart, brain, eyes, and joints, few studies have examined possible effects on lifespan. Those few studies also had significant limitations – they used diet records which carry little weight due to imprecisions in getting true EPA and DHA intakes. Studies using biomarkers, such as blood levels of omega-3s, are much more precise because the exposure variable is objective.
 
The report comprised an analysis of pooled data from 17 separate cohorts globally, which included 42,466 people who were followed for an average of 16 years – during that timespan, 15,720 people died. When FORCE researchers examined the risk for death from any cause, the people who had the highest omega-3 index, at the 90^th percentile, had a 13% lower risk for death than people with EPA and DHA levels in the 10^th percentile. When they looked at the three major causes of death, cardiovascular disease, cancer, and all other causes combined, they saw significant risk reductions of 15%, 11%, and 13% respectively.
 
The range between the 10^th and 90^th percentile for EPA and DHA levels, in terms of red blood cell concentrations, spanned about 3.5% to 7.6%. Other studies have found that having an omega-3 index of 8% or higher is optimal.
 
The authors noted in the paper that these findings suggest the overall mortality risk reductions offered by having a high EPA and DHA level may extend beyond cardiovascular diseases, and that omega-3s may have more wide-ranging effects on overall health and the aging process. None of these same effects had any clinical significance for the non-marine ALA, an omega-3 fatty acid sourced from plants.
 
“Since all of these analyses were statistically adjusted for multiple personal and medical factors (i.e. age, sex, weight, smoking, diabetes, blood pressure, etc., plus blood omega-6 fatty acid levels), we believe that these are the strongest data published to date supporting the view that over the long-term, having higher blood omega-3 levels can help maintain better overall health,” Dr. Bill Harris, founder of the Fatty Acid Research Institute (FARI), and lead author on this paper, said.
 
Dr. Harris co-developed the Omega-3 Index test 17 years ago as an objective measurement of a person’s omega-3 status. Measuring omega-3s in red blood cell membranes offers an accurate picture of one’s overall omega-3 intake during the last four to six months, and, to date, the Omega-3 Index has been featured in more than 200 research studies.
 
“This comprehensive look at observational studies of circulating omega-3 fatty acids indicates that the long chain omega-3s EPA, DPA, and DHA, usually obtained from seafood, are strongly associated with all-cause mortality, while levels of the plant omega-3 alpha-linolenic acid (ALA) are less so,” Tom Brenna, PhD, professor of Pediatrics, Human Nutrition, and Chemistry, Dell Medical School of the University of Texas at Austin, said.