Omega-3 Fatty Acids Are Linked to Longevity

Omega-3 fatty acids, from fish like salmon and other sources, have for years been shown to help lower levels of heart disease and cardiac death.

New research suggests the fatty acids may possess an even more fundamental benefit: Heart patients with high omega-3 intake had relatively longer “telomeres,” which are stretches of DNA whose length correlates with longevity.

Researchers at the University of California, San Francisco, have discovered that omega-3 fatty acids protect heart cells from cellular aging. People with high levels of omega-3 had an associated lower rate of telomere shortening.

Ramin Farzaneh-Far, M.D., of the University of California, San Francisco, and colleagues conducted a study to determine whether omega-3 fatty acid blood levels were associated with changes in leukocyte (a type of blood cell) telomere length in a study of 608 outpatients with stable coronary artery disease. The patients were recruited between September 2000 and December 2002 for the Heart and Soul Study, and followed up to January 2009 (median [midpoint], 6.0 years). The researchers measured leukocyte telomere length at the beginning of the study and again after 5 years of follow-up. Multivariable models were used to examine the association of baseline levels of omega-3 fatty acids (docosahexaenoic acid [DHA] and eicosapentaenoic acid [EPA]) with subsequent change in telomere length.

The researchers found that individuals in the lowest levels of DHA+EPA experienced the most rapid rate of telomere shortening, whereas those in the highest levels of  DHA+EPA experienced the slowest rate of telomere shortening.

“Levels of DHA+EPA were associated with less telomere shortening before and after sequential adjustment for established risk factors and potential confounders. Each 1-standard deviation increase in DHA+EPA levels was associated with a 32 percent reduction in the odds of telomere shortening,” the authors writes.

A telomere is a repeating DNA sequence (for example, TTAGCG) at the end of the body’s chromosomes. The telomere can reach a length of 15,000 base pairs. Telomeres function by preventing chromosomes from losing base pair sequences at their ends. They also stop chromosomes from fusing to each other. However, each time a cell divides, some of the telomere is lost (usually 25-200 base pairs per division). When the telomere becomes too short, the chromosome reaches a “critical length” and can no longer replicate. This means that a cell becomes “old” and dies by a process called apoptosis.