My dissertation research focused on the omega-3 fatty acids found in fish, so naturally it caught my attention when I started seeing ads touting fish oil pills as a “Fountain of Youth” anti-aging remedy. Surprisingly, when I looked into the scientific evidence, I found a kernel of truth at the bottom of the mountain of hype. So, should you smear fish oil on your face and walk around smelling like a sardine factory? Well, no. That would be crazy. But after reading the evidence, you might feel more inclined to order salmon for dinner, or you might even want to start taking fish oil pills.
Cellular Aging
The omega-3 fatty acids we’re talking about here are those found in fatty fish, like salmon, sardines or herring. All the hype really started from a 2010 study published in the journal JAMA, which found that people with high levels of the omega-3 fatty acids found in fish had longer structures called telomeres in their blood cells. Telomeres act like a protective cap on the ends of chromosomes, but they get shorter when cells are exposed to environmental stresses that trigger aging, like sun exposure. The same processes that make skin sag and wrinkle also shorten telomeres, and people with shorter telomeres have higher risk for death from age-related diseases like cancer and cardiovascular disease. As a result, the length of telomeres is like a biological clock, indicating that the fish eaters had biological ages younger than their chronological ages.
Staying Sharp
Perhaps even more important than not dying is continuing to lead a normal life in old age, and for that, staying mentally sharp is critical. At least three studies have found an association between fish consumption and slower rates of mental decline with aging. However, randomized clinical trials for Alzheimer’s Disease have so far only found a benefit of omega-3 supplements for people in the very earliest stages of mental decline. This may just mean that fish oil is only helpful if people start taking it while they are still relatively healthy.
Which came first, the chicken or the egg?
On the other hand, critics and seafood-haters like to point out that most of these results could just be due to coincidence. People who eat a lot of fish, or who go to the trouble to take fish oil pills, are probably health freaks in other ways, and have a whole constellation of healthy habits that may add up to make these people age more slowly. However, researchers in the field point to direct experiments in lab animals as evidence these effects are really due to fats in fish: for example, omega-3 supplementation in mice led to slower mental decline with aging, and longer life spans. (Note that most omega-3 researchers, including myself, aren’t waiting for clinical trial evidence to start taking fish oil or to make eating fish a priority. Interestingly, the pioneers in the field are now elderly, but seem to be aging remarkably well.)
Bottom Line
In the quest to delay aging, fish oil can’t hurt, and might help. Even if it doesn’t, there are other good reasons to eat fatty fish, like the well established benefit of preventing cardiovascular disease. Try to avoid types of fish that can have high mercury content, such as farm-raised salmon. Fish oil pills are safe as long as you keep to recommended doses (below 3 grams per day). But watch out for products that claim to have added omega-3’s; this usually refers to flax seeds, which may not have the same benefits as the omega-3 fatty acids in fish.
