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Can more omega-3 in the blood increase your life span?

Can more omega-3 in the blood increase your life span?Apparently so. Omega-3 is a class of essential fatty acids with a host of different functions in the body. We primarily get omega-3 from oily fish but it is also found in certain other foods. Our intake of omega-3 has been reduced substantially as a result of altered diets and the use of unnatural animal feed. It appears that having more omega-3 in the blood can help us live longer. This was shown in a study that is published in American Journal of Clinical Nutrition. The question is how do we get enough omega-3?

Omega-3 and omega-6 are essential fatty acids that we humans are unable to synthesize in the body. Therefore, we need to get them from different dietary sources. Both omega-3 and omega-6 fatty acids are found in our cells membranes where they work together in an intricate biochemical interplay. It is important to get them in the proper ratio. We primarily get omega-6 from plant oils and industrially processed foods, while we primarily get omega-3 from oily fish. The problem with modern diets is that they often contain far too much omega-6 and too little omega-3. This is a problem because of omega-3’s numerous functions such as:

  • Helping to build cell membranes
  • Brain and nervous system
  • The retina of the eye
  • Cardiovascular functions
  • Immune defense and regulation of inflammatory processes
  • Keeping skin and other tissues soft and pliable

How can omega-3 affect our lifespan?

The new study was conducted at Hospital del Mar Medical Research Institute (IMIM) in Barcelona and at The Fatty Acid Research Institute (FARI) in Sioux Falls, South Dakota, USA. The aim of the study was to investigate how omega-3 fatty acids affect our life expectancy. The relative percentage of omega-3 fatty acids in relation to other lipids in our cell membranes is called the “omega-3 index”. For a period of 11 years, the scientists followed 2,240 participants with an average of 65 years. Blood levels of omega-3 were measured in all participants. Afterwards, the people were divided into four groups:

  • Non-smokers with high omega-3 levels
  • Smokers with high omega-3 levels
  • Smokers with low omega-3 levels
  • Non-smokers with low omega-3 levels

The scientists used the Kaplan-Meier curve, which is a highly reliable method used to estimate the survival function. Over the course of the 11 years that the study lasted, 384 out of 2,240 participants died.

What is the omega-3 index?

The omega-3 index is a simple measure of the relative amount of EPA and DHA in the membranes of the red blood cells. If you have, say, 64 fatty acids in a red blood cell membrane and three of them are EPA and DHA, your omega-3 index is 4.6%. The higher your index is, the better it is for your overall health. According to the new research paper, a low omega-3 index is just as powerful in predicting early death as smoking.

High blood levels of omega-3 increase life expectancy by around five years

According to the researchers’ analysis, non-smoking participants with high blood levels of omega-3 had the highest life expectancy. Smokers with high blood levels of omega-3 had approximately the same life expectancy as non-smokers with low omega-3 levels in their blood. Finally, smokers with low omega-3 levels in their blood had the shortest life expectancy. According to the results, smoking reduced lifespan by 4.7 years on average, while having high omega-3 levels in the blood increased lifespan by the same number of years. The new study is published in The American Journal of Clinical Nutrition. According to lead researcher, Dr. Aleix Sala-Vila, this study confirms earlier studies.

»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.«
Dr. Aleix Sala-Vila

Oily fish and fish oil as part of a healthy diet

Dr. Williams S. Harris, a co-author of the study, tells MedicalNewsToday that doctors should encourage their patients to consume more omega-3 because it also helps reduce other important risk factors such as cholesterol and blood pressure. It appears that a person’s omega-3 index is important for both cholesterol and blood pressure, and it is also easy, cheap, and safe to eat more fish or to take a fish oil supplement.
In addition, fish contains other beneficial nutrients such as vitamin D, selenium, and zinc. The researchers also mention that people who consume more oily fish have a healthier lifestyle, which may have affected the study results. They explain that fish oil supplements can not be used to cancel out the negative effect of smoking.

Omega-3 sources:

  • ALA: Mainly flaxseed oil and rapeseed oil, walnuts, and chia seeds
  • EPA and DHA: Oily fish, fish oil supplements, and cod liver oil

Note: Many people have difficulty with converting ALA into EPA and DHA

How do we get enough omega-3?

It is primarily the two omega-3 fatty acids, EPA and DHA, that have many different physiological functions in the body. They are incorporated into cell membranes, they regulate inflammatory processes, they are involved in our lipid balance, etc. EPA and DHA are found in oily fish, shellfish, fish oil supplements, and cod liver oil. You get an adequate amount of EPA and DHA if you eat 50-100 grams of oily fish (herring, anchovies, or mackerel) every day. Farmed salmon contains around half as much omega-3 as wild salmon because of the unnatural feed that is given to farmed fish. Predatory fish like tuna that belong to the upper part of the food chain contain more mercury and other environmental toxins. Therefore, you should be careful not to eat this type of fish in large quantities. We need around 500 mg of EPA and DHA every day. Certain conditions such as inflammation may increase your need for EPA and DHA to around 1,000 – 2,000 mg. You can read on the package label how much EPA and DHA is in the fish oil supplements you buy.


Michael McBurney et al. Using an erythrocyte fatty acid fingerprint to predict risk of all-cause mortality: the Framingham Offspring Cohort. The American Journal of Clinical Nutrition. 2021

Erika Watts. Omega-3 levels in the blood may boost life span. MedicalNewsToday 2021

The Norwegian University of Science and Technology (NTNU). Understanding how omega-3 dampens inflammatory reactions. ScienceDaily 2017

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