Are Omega-3 Fats the Key to a Long and Healthy Life? New Study Finds Omega-3 Supplements Diminish Stress-Induced Cellular Aging
From the salty salmon in Scandinavia to the sardines swimming in the Mediterranean Sea to the fatty tuna consumed by centenarians in Okinawa, Japan, many countries around the world are heavy consumers of seafood rich in omega-3 fats. Eating fish and seafood has long been recommended as part of a healthy diet, as these water-dwelling animals are loaded with protein, vitamins, minerals, and fats — especially the health-promoting omega-3s. However, most Americans tend to be relatively low consumers of healthy fish and seafood, leading many doctors and researchers to recommend taking omega-3 supplements to pick up the slack.
With benefits ranging from cardiovascular to cognitive to cosmetic, adequate omega-3 consumption has been linked to healthier aging, reduced risk of chronic diseases, and increased longevity. One lesser-studied area of omega-3’s impact on human health involves our body’s internal stress responses, which are thought to play a significant role in both physical and mental health disorders.
With this theory that these healthy fats can mitigate dysregulated stress responses, researchers out of Ohio State University looked at how supplemental omega-3s impact biomarkers of stress, inflammation, and cellular aging in a group of sedentary, middle-aged, and overweight adults — a subset of people at high risk for accelerated aging. Published recently in Molecular Psychiatry, Madison and colleagues show that omega-3 supplements are a strong contender for fighting the internal signs of aging caused by stress, which could be one way that omega-3 fats boost longevity.
Omega-3 Fats Fight Aging
Several studies have linked omega-3 fat consumption to boosted longevity, both from population-based research looking at lifespan, and studies that look at internal aging biomarkers, like telomeres. Telomeres are the endcaps on the tips of our chromosomes, protecting sensitive genetic information from being snipped off during cell divisions. Instead, these protective endcaps shorten with each cell division to save the rest of the DNA within the chromosome. With this gradual shortening, telomeres can be used as a proxy for biological age — rather than the birthday-based chronological age we celebrate each year, biological age measures how quickly your cells, organs, and tissues are aging.
In a study published in JAMA, adults who had the highest blood levels of two types of omega-3s (DHA and EPA) exhibited the slowest rates of telomere shortening over a 5-year period, compared to those with the lowest DHA and EPA levels. This slowing of internal aging from omega-3s has also translated to longer lifespans. One recent study of over 42,000 individuals found that people with the highest blood levels of omega-3 fats had a 15-18% reduced risk of dying from any cause over 16 years compared to those with the lowest levels.
How Stress Ages Us
As blood levels of omega-3 fats have been linked to increased longevity and slower internal aging, Madison and colleagues aimed to uncover if one potential reason behind these benefits was omega-3’s role in dampening the stress response. After a stressful situation — this could be psychological stress, like being put on the spot for an impromptu speech, or internal stress, like smoking a pack of cigarettes — levels of the stress hormone cortisol and pro-inflammatory molecules called cytokines are elevated.
Although levels of cortisol, our body’s primary stress hormone, naturally rise and fall throughout the day, overly exaggerated cortisol responses from repeated stressors are linked to shorter telomeres, chronic inflammation, and oxidative stress — a buildup of reactive molecules that damage cells and DNA and accelerate aging.
In this study, the Ohio State research team used a well-known test to induce stress, which involves giving a speech on camera and doing complicated math problems out loud to a panel of judges. To assess omega-3’s effects on mitigating this stress response — and its subsequent impacts on inflammation, oxidative stress, and biological aging — Madison and colleagues tested two doses of supplemental omega-3 fats in a group of 138 sedentary, overweight, and middle-aged adults. For four months, the adults took a daily supplement of either 2.5 grams of omega-3s (equivalent to about a 5-ounce portion of salmon), 1.25 grams of omega-3s, or a placebo.
Suppressing Stress With Omega-3s
After taking the supplements for four months, those in the high-dose omega-3 group had significantly lower cortisol responses throughout and after the stress test, with a 19% reduced cortisol release compared to the placebo group. The low-dose omega-3 group did not show any differences compared to the placebo group, suggesting that 1.25 grams of omega-3s per day is an insufficient dose to thwart an exaggerated stress response.
The researchers also looked at internal inflammation by measuring levels of two cytokines, one that tends to be pro-inflammatory, interleukin-6 (IL-6), and the anti-inflammatory IL-10. Both omega-3 groups experienced higher IL-10 levels two hours after the stress test, while the placebo group had declines in the anti-inflammatory cytokine.
Conversely, the high-dose omega-3 group saw lower IL-6 levels after the stress test, with a 33% reduction compared to the placebo group, while the low-dose omega-3 group did not have significantly lower IL-6. An imbalance of pro- and anti-inflammatory cytokines promotes increased oxidative stress, which, in turn, creates more inflammation in the body and quickens internal aging. Similar to the cortisol tests, these markers indicate that 2.5 grams of omega-3s are the optimal dose to flip the cytokine signaling pathways from pro-inflammatory to anti-inflammatory.
Tamping Down on Telomere Loss
The research team also looked at levels of telomerase — the enzyme that maintains and restores telomere length — in immune cells called peripheral blood lymphocytes. It was hypothesized that omega-3 supplements could mitigate telomere attrition, as high cortisol and inflammation are thought to play a role in their shortening. As stated by lead author Annelise Madison, "The assumption based on past work is that telomerase can help rebuild telomere length, and you want to have enough telomerase present to compensate for any stress-related damage.”
They found that although telomerase levels did not increase in the omega-3 groups, both doses maintained and prevented the rapid drop in telomerase seen in the placebo group, which was reduced by 24% two hours after the stress test. This indicates that, without the stress-buffering effects of omega-3s, telomerase will likely drop after stressful events, reducing the ability to repair lost telomere length. In those with chronic stress, this would lead to rapidly shortening telomeres and subsequently accelerated aging.
A Serving of Salmon Per Day Keeps the Stress Away
While the higher dose of 2.5 grams per day of omega-3s did show the most significant benefits in dampening the cortisol stress response and lowering inflammatory cytokines, the smaller amount of 1.25 grams was still able to ward off the post-stress drop in telomerase and reduction in anti-inflammatory IL-10.
As this study sample was made up of sedentary, overweight, and middle-aged adults, the results will likely translate to a large proportion of the American population. These results suggest that a daily supplement of omega-3 fats could mitigate the damaging effects of stress — and, hopefully, reduce the risk of physical and mental disease that comes with chronic stress.
Although these findings are preliminary, they suggest that supplemental omega-3 may limit the impact of repeated stress on cellular aging, which could translate to increased longevity. As concluded by Madison, “The findings suggest that omega-3 supplementation is one relatively simple change people could make that could have a positive effect at breaking the chain between stress and negative health effects." Until we have more research to back this up, we could try to eat more omega-3-rich seafood — a serving of salmon per day would be suf-fish-cient to keep the stress away!
Farzaneh-Far R, Lin J, Epel ES, Harris WS, Blackburn EH, Whooley MA. Association of marine omega-3 fatty acid levels with telomeric aging in patients with coronary heart disease. JAMA. 2010;303(3):250-257. doi:10.1001/jama.2009.2008
Harris WS, Tintle NL, Imamura F, et al. Blood n-3 fatty acid levels and total and cause-specific mortality from 17 prospective studies. Nat Commun. 2021;12(1):2329. Published 2021 Apr 22. doi:10.1038/s41467-021-22370-2
Madison AA, Belury MA, Andridge R, et al. Omega-3 supplementation and stress reactivity of cellular aging biomarkers: an ancillary substudy of a randomized, controlled trial in midlife adults [published online ahead of print, 2021 Apr 20]. Mol Psychiatry. 2021;10.1038/s41380-021-01077-2. doi:10.1038/s41380-021-01077-2