With Lee Hooper, PhD, Andrew Freeman, MD, and Rai-Chi Huang, MD, PhD
Omega 3 fatty acids—found in supplements and naturally in some foods like certain fish, and nuts and seeds—have long been touted for their health benefits, especially heart health. Yet a lot is still unknown, including whether it's better to your omega 3 fats from pills or in food—and the debate continues regarding how much they may actually help you avoid heart disease.
Recent studies on omega 3 fatty acids and heart health are shedding a bit more light on this ongoing controversy. And the evidence, at least from a recent analysis, is pointing to foods over supplements when it comes to helping your heart—and not to expect the moon.
Omega 3 supplements are worthwhile only if you have high triglycerides, otherwise stick to foods for heart health.
A Crash Course on Omega 3 Fatty Acids—What Are They and Why Do We Need Them?!
To put this topic into proper context, it’s helpful to know that there are three different types of omega 3 fats:
- ALA (alpha-linolenic acid)f
- EPA (eicosapentaenoic acid)
- DHA (docosahexaenoic acid)
ALA is an essential fatty acid, which means that you need it but you must get this fat from your diet because your body is unable to produce it. In general, omega 3 fats are a crucial component of all cell membranes, including the eye (retina) and brain as well as aiding in the process of energy production to support functions involving the heart, lungs, immune system, and hormones (endocrine system), work properly.1
Your body can convert some ALA into EPA and then DHA, but not enough to meet all your body’s needs but the best way to assure you are getting enough heart healthy fats is to eat foods high in the omega 3 fats, and if you can’t or don’t get enough of these necessary fats in your diet, you might consider taking an omega 3 supplement to boost these needed fats. More on this later.
One important note—if you are taking a medication for blood clotting, you should discuss the need for a fish oil supplement with your doctor before you begin taking it; this is because omega 3 fatty acids interact in a way that could cause a serious bleeding problem.
Omega 3 fatty acids are monounsaturated fats that come from food sources—primarily cold water fish (eg, salmon, trout, tuna, mackerel, and herring)—that contain EPA (eicosapentaenoic acid) and docosahexaenoic acid (DHA). Other fatty acids are derived from plant-derived sources of food—including nuts (especially walnuts) and seeds (eg, flax, chia, sunflower)—that have primarily ALA (alpha-linolenic acid).
Omega 3 supplements, also known as fish oil pills, contain both EPA and DHA types of omega 3 fatty acids.
Evidence for Taking Omega 3 Pills: Supplements Offer No Help
In a major analysis, researchers commissioned by the World Health Organization, examined the data to determine whether omega 3 fatty acids have any benefits for heart health, including preventing first time cardiovascular disease (CVD) from the beginning as well as other health problems.
"We tried to bring together all of the high-quality studies that looked at omega 3 fats and cardiovascular outcomes,'' says Lee Hooper, PhD, RD, the study's lead author and a researcher at Norwich Medical School at the University of East Anglia in the United Kingdom.
Her team identified 79 randomized clinical trials, considered the gold standard in scientific research, to evaluate the evidence.2 In all, the studies included 112,000 men and women who were followed for at least a year and sometimes up to eight years.
Most of the studies involved omega 3 supplements, with very few measuring the amount of oily fish and plant-based omega 3s, the ALAs that were consumed. There were not enough food-related studies to make a solid conclusion about whether dietary sources of omega 3s were beneficial or not.
"What we found was not encouraging; in fact, we didn't see anything" in terms of CVD benefit, Dr. Hooper tells Endocrine Web. "It really doesn't seem that taking an omega 3 supplement affects our cardiovascular health in any good way," she says.
Overall Benefits to Heart Seem Unlikely, But Omega 3s Do Reduce Triglycerides
The studies evaluated the effects of omega-3 on the rate of deaths from heart disease, all causes, heart attack, strokes, and heart arrhythmias (irregular heartbeats).2 In effect, omega 3 fats simply didn't help or harm.
They did find a very small beneficial effect from ALAs, which may slightly reduce the risk of heart attacks and perhaps death from heart disease but the effect is small, Dr. Hooper says. She estimates that “it would translate to 1 in 1,000 persons who might get some a benefit.”
However, the researchers do have some good news. They concluded that omega 3 fatty acids do appear to reduce the type of blood cholesterol known as triglycerides, but that supplements probably are not useful for preventing or improving heart and circulatory problems. And, upping your intake of plant-based omega 3s high in ALA (ie, walnuts, flaxseed and flax oil, chia seeds) may help your heart somewhat.2
For Omega 3 Fats, Pick Foods Sources Over Fish Oil Supplements
Cardiologists say it's best to get your omega 3s from foods, not omega 3 pills based on another review of evidence published in medical journals.3
Andrew Freeman, MD, FAAC, FACP, associate professor and director of cardiovascular prevention and wellness at National Jewish Health, in Denver, Colorado, and his colleagues looked at several trending controversies about nutrition and heart health, including the role of omega-3s in CVD.3
"There appear to be some benefits from eating certain fish," he tells EndocrineWeb. However, he adds that there are a number of concerns, too, about fish—their declining populations and contamination with heavy metals like mercury (especially high in albacore tuna), for instance.
"We are pushing [people] towards eating more plant-based omega-3 fats," he says. But he isn't completely down on fish.
"Fish is still the mainstay of the diet in many parts of the world where there is very little heart disease," he says. "I think when you replace higher fat foods and highly processed foods with fish there is going to be some benefit.'' So it may be that by substituting fish for red meats, bacon and luncheon meats, and similar high-fat foods, you are making a change that will lead to improving your health outcomes, he says.
Another reason to consider your source of omega 3 fats, he says, eating more plant-based foods means a ''cleaner" diet. However, ''our bodies are not very efficient at converting plant sources of omega-3 [ALA to DHA and EPA], so you may need to eat more of them to get enough beneficial fats."
Easy ways to get enough omega 3 fats in your diet, he says: Put a tablespoon of ground flaxseed in your oatmeal. Throw some walnuts in your salad or stirfry. Make chia breakfast pudding or sprinkle some in your yogurt.
His evidence review, like the Cochrane research analysis, suggests some cardiovascular health improvement may result when a diet contains plenty of foods rich in omega-3s. Yet, he emphasizes that he prefers food to supplements.
"I usually tell those people who are taking fish oil capsules to come off them unless they are prescribed omega 3 supplements for a high triglyceride level," Dr. Freeman says.
It Seems There May Be Some Benefit to Early Supplementation, In Babies
In another study, Australian researchers looked at whether giving infants added omega-3 fatty acids might improve health,4 including reducing their risk for heart disease. They gave 420 infants either an omega 3 supplement or olive oil from birth through six months, then revisited that at age 5 years to see if either group appeared healthier from a heart risk point of view.
The children who received a supplement with omega 3 fats had a smaller waist circumference (one risk factor for heart disease) at age 5 than those who had olive oil. The boys, but not the girls, who were given omega 3 fatty acids also had better insulin profiles than those who got the olive oil.4
"These findings suggest a potential benefit to future heart health from early supplementation with omega-3s during infancy," Rae-Chi Huang, MD, PhD, associate professor at the University of Western Australia, Perth, told EndocrineWeb.
However, he stresses that longer-term studies are needed before it would be prudent to advocate that everyone consider giving babies omega 3 supplements, he says. For now, it’s interesting but too soon to act.
So Is the Story on Omega 3 Fatty Acids Over?
The studies examining the possible benefits of omega-3s continue. Researchers are looking at a range of health outcomes and the impact of a heart healthy diet rich in omega 3 fatty acids on a range of chronic disease. For instance, Dr. Hooper's team is beginning to evaluate the effects that omega-3 fats may have on diabetes, dementia, and some cancers.
So the full story may be known quite yet. But the enthusiasm for omega 3 supplements should be curtailed other than for reducing high triglycerides. Best to spend your money of salmon, trout, and walnuts.
Last updated on 08/06/2018
Heart Healthy Diet to Improve Cardiovascular Health, Lower Diabetes Risk