Higher Levels of This 1 Thing in the Blood Is Linked to a Longer Life, According to New Research

Being optimistic, eating these 9 foods (beans, whole grains and salmon for the win!) and following these 7 secrets have all been proven to help improve the chances that we'll lead longer, healthier lives.

And now, new research adds another detail that certainly can't hurt in our overall longevity landscape. A study published June 16 in The American Journal of Clinical Nutrition found that having higher levels of omega-3 fatty acids in the blood is associated with a life expectancy of 5 years longer than their low-omega-3 peers.

We've known for years that omega-3 fats—the heart-healthy kind found in salmon, mackerel, sardines, these 8 vegan sources and more—can reduce risk for certain cancers, heart disease and chronic inflammation. And this study builds on the evidence that omega-3s are a boon for our health.

Grilled Fish with Peperonata
Grilled Fish with Peperonata

Scientists at the Hospital del Mar Medical Research Institute (IMIM) in Barcelona, The Fatty Acid Research Institute in the United States and several universities in the United States and Canada dove into 11 years of data from 2,240 people over the age of 65 enrolled in the Framingham Offspring Cohort. Their goal was to see how fatty acid levels in the blood might be related to mortality. Four types of fatty acids, including omega-3s, contribute to a longer life expectancy.

"Having higher levels of these acids in the blood, as a result of regularly including oily fish in the diet, increases life expectancy by almost five years," says Aleix Sala-Vila, Ph.D., a postdoctoral researcher in the IMIM's Cardiovascular Risk and Nutrition Research Group and author of the study. By comparison, "being a regular smoker takes 4.7 years off your life expectancy, the same as you gain if you have high levels of omega-3 acids in your blood."

Just a 1% increase of omega-3s in the blood is enough to move the needle, Dr. Sala-Vila confirms in a research brief by Institut Hospital del Mar d'Investigacions Mèdiques in Barcelona. The adequate intake suggested by the National Institutes of Health: 1.1 grams per day for adult females and 1.6 grams per day for adult males. For reference, 1 tablespoon of flaxseed oil has 7.26 grams, 1 ounce of English walnuts has 2.57 grams, 3 ounces of wild Atlantic salmon has 1.57 grams and 1 tablespoon of canola oil has 1.28 grams.

Related: Healthy Omega-3 Recipes

While they still need to test this theory on a larger pool of individuals outside of the U.S. and with broader economic and racial diversity, Dr. Sala-Vila says that the length and scope of this study means that, "what we have found is not insignificant. It reinforces the idea that small changes in diet in the right direction can have a much more powerful effect than we think, and it is never too late or too early to make these changes."

Whole foods are always going to be your best bet over supplements, although the latter can help fill in the gaps if needed. Since oily fish are high in protein and two of the more potent forms of omega-3 (eicosapentaenoic acid, or EPA, and docosahexaenoic acid, DHA; both of which are found to be easier for the body to utilize than the alpha-linolenic acid, or ALA, found in plant-based sources), the American Heart Association recommends eating two 3 ½-ounce servings of low-mercury, fatty fish at least twice a week.

If you think you might be coming up shy, a speedy at-home test like this Omega Quant Omega-3 Index Blood Test Kit (buy it: $49.95, Amazon) can confirm or deny. Simply use the kit to submit a blood sample and they'll email you within a week or two about your current blood levels of omega-3s.

Up next: Doing This Walking Workout Every Day Could Help You Live Longer.