Telomeres, structures at the end of chromosomes that are involved in the stability and replication of chromosomes, are markers of biological aging. Genetic factors, exposure to certain chemicals and environmental stressors shorten the length of telomeres and are believed to contribute to the aging process. New research just published in the Journal of the American Medical Association (JAMA) shows that omega-3s slow down the shortening of telomeres -- this means omega-3 fatty acids may protect against aging on a cellular level.
Previous studies have shown that people with established cardiovascular disease who have a high dietary intake of marine omega-3 fatty acids live longer than others with the same health problems who do not have adequate omega-3s in their diet. However, the exact way omega-3s exert this protective effect is not well understood, according to background information in the JAMA study.
So Ramin Farzaneh-Far, M.D., of the University of California, San Francisco, and colleagues decided to investigate whether omega-3 fatty acid blood levels were linked to changes in leukocyte (a type of blood cell) telomere length in a study of 608 people who had stable coronary artery disease. The scientists studied the patients for about five years, measuring leukocyte telomere length at the beginning of the study and at the end of 5 years of follow-up. Their goal? To see if there was any association between baseline levels of two types of omega-3 fatty acids -- docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) -- in the patients' bodies and any subsequent change in telomere length. There was.
The scientists found that the research subjects with the least amount of DHA and EPA experienced the most rapid rate of telomere shortening. However, those with the highest levels of the omega-3 fatty 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 wrote in their study. "These findings raise the possibility that omega-3 fatty acids may protect against cellular aging in patients with coronary heart disease."
This also raises the very real possibility that an abundance of omega-3s in the diet could offer protection from cellular aging for all people -- whether they have heart disease or not.