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Could omega-3 be associated with life span? Jonathan Knowles/Getty Images
  • Omega-3 fatty acids are polyunsaturated fatty acids that occur widely in nature and appear in certain foods.
  • A new study has explored whether or not there is any connection between omega-3 and human life expectancy.
  • The researchers found that having higher levels of omega-3 in the blood could predict a lower mortality rate in people over the age of 65 years.

It is not unusual to walk into a pharmacy or nutrition store and find rows of supplements containing omega-3 fatty acids. It is no secret that this particular fatty acid has a range of health benefits.

A new study that appears in The American Journal of Clinical Nutrition now suggests that it might also add years to one’s life.

According to the National Institutes of Health (NIH), omega-3 is one of the two main types of polyunsaturated fatty acids. These acids, which contribute to forming cell membranes, are considered “essential” since the body cannot make them on its own.

The NIH says that omega-3s “provide energy for the body and are used to form eicosanoids,” which affect the body’s cardiovascular, pulmonary, immune, and endocrine systems.

There are three primary types of omega-3 fatty acids: alpha-linolenic acid, eicosapentaenoic acid, and docosahexaenoic acid (DHA). People commonly take DHA supplements during pregnancy, as they can help with fetal development.

Aside from supplements, some sources of omega-3s include:

  • flaxseed oil
  • soybeans
  • canola oil
  • certain fish, including salmon, tuna, and sardines
  • chia seeds

The NIH also notes that some studies have suggested that diets high in omega-3s are linked to lower rates of cancer, a reduced risk of Alzheimer’s disease, and a reduction in the symptoms of rheumatoid arthritis.

The recent study involved the Hospital del Mar Medical Research Institute (IMIM) in Barcelona, Spain, and the Fatty Acid Research Institute (FARI) in Sioux Falls, SD.

The researchers’ goal was to find out what role omega-3 plays in life expectancy. They tracked 2,240 participants over 11 years and analyzed omega-3 levels in the participants’ blood.

They divided the study participants into four groups:

  • people with a high omega-3 level who did not smoke
  • people with a high omega-3 level who did smoke
  • people with a low omega-3 level who did not smoke
  • people with a low omega-3 level who did smoke

According to the study authors, “Kaplan-Meier survival curves were used to estimate survival proportions by age given different risk profiles.”

According to their analysis, people with high omega-3 levels in their blood who did not smoke had the highest survival estimate. People with high omega-3 levels who did smoke and those with low omega-3 levels who did not smoke were almost identical in terms of survival estimates.

Finally, people with low omega-3 levels in their blood who did smoke had the lowest survival estimate.

“This reaffirms what we have been seeing lately,” says study author Dr. Aleix Sala-Vila, a postdoctoral researcher in IMIM’s Cardiovascular Risk and Nutrition Research Group.

“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 5 years.”

– Dr. Aleix Sala-Vila

“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.”

Study co-author Dr. William S. Harris, the president and founder of the FARI, spoke with Medical News Today about the results of the study.

He explained that doctors should encourage their patients to increase their omega-3 levels alongside addressing the other important risk factors, such as cholesterol and blood pressure.

“Knowing a person’s omega-3 index is just as — if not more — important than knowing a person’s cholesterol level or blood pressure, and ‘fixing’ the omega-3 index is much easier (and cheaper and safer) than treating all those other risk factors; eat more fish and/or take an omega-3 supplement.”

A person should talk with a doctor to learn about their own personal risk factors and whether or not they require medical treatment.

The study did have certain limitations. For example, Dr. Harris explained to MNT that, because of the study design, “You cannot be sure that some other factor that is associated with higher omega-3 levels — such as a healthy lifestyle — isn’t really what’s important in predicting risk for death.”

“So, we can’t conclude that there is an ‘effect’ of higher omega-3 on risk for death; all we can say is that there is ‘an association’ between higher omega-3 levels and risk for death,” he added.

Speaking with MNT, Dr. Harris also wanted to make it clear that although people with high omega-3 levels who did smoke and people with low omega-3 levels who did not smoke had almost identical survival estimates, “this should not be taken to mean that somehow taking fish oil capsules ‘erases’ the bad effects of smoking.”

The researchers plan to expand their study to participants who are not based in the United States. They want to see whether or not their findings are consistent with people from different backgrounds.

Kristin Kirkpatrick, a nutritionist with a master’s degree in health management and the founder of KAK Consulting, was not involved with the study but spoke with MNT about its findings.

“It’s notable that this study not only looked at the benefit that overall omega-3 fatty acid intake may have in benefiting longevity, but also that it can lead to diet recommendations based on biomarkers, such as blood concentrations of types of omega-3s.”

“The article also recommended discussing consuming fatty fish as well,” said Kirkpatrick. “This is consistent with other studies, which show that fatty fish consumption can benefit brain health (including mental health outcomes) and longevity. I’m not surprised by the research but would love to see if outcomes are consistent between both supplemental and whole food forms.”

The study authors noted a few conflicts of interest regarding the study. For instance, lead author Dr. Michael I. McBurney consults with OmegaQuant Analytics, which is a laboratory that offers omega-3 blood testing. Dr. Harris also holds an interest in OmegaQuant Analytics.

Also, Dr. Sala-Vila received institutional research funding and support to attend professional meetings from the California Walnut Commission.