Other plant-based omega-3 food sources include seaweed, walnuts, edamame (soybeans), flax seeds, chia seeds, and hemp seeds. “Fortified foods like omega-3-enriched eggs and certain dairy products can also provide some omega-3s in the diet,” says Amy Goodson, a nutritionist and registered dietitian based in Dallas. Another beneficial omega-3 is known as alpha linolenic acid (ALA), which is found abundantly in canola and soybean oils.
No matter which animal-based or plant-based options you consume, “we know it’s preferable to increase omega-3 intake from foods rather than from supplements,” says JoAnn Manson, chief of preventive medicine at Brigham and Women’s Hospital and Harvard Medical School and the principal investigator of key omega-3s VITAL research.
Why fish oil supplements are not all they’re cracked up to be
Omega-3 properties are most powerful when they come directly from food—which offers a wider array of nutrients and more concentrated amounts of EPA, DHA, and ALA. There’s also a difference in the chemical structure of the fat in whole fish versus extracted fish oil, says Monti; and the manufacturing process can degrade the quality of nutrients in supplements and can even introduce worrisome contaminants.
An even more compelling reason to stick with food over omega-3 supplements? The purported cardiovascular benefits of fish oil supplements remain largely unproven in healthy people. “A lot of people became obsessed with fish oil about two decades back because there was initially some compelling data on improved heart health,” says Freeman, “but this data has since been largely refuted.”
(5 things you should know before trusting that supplement.)
Indeed, much of this early research relied almost entirely on observational studies that were unable to prove causation. In subsequent randomized controlled trials—where causation can be measured—”supplementation with omega-3 fatty acids have shown no benefits,” says Steven Nissen, chief academic officer of the Cleveland Clinic Heart, Vascular, and Thoracic Institute. Many recent randomized trials have even tested fish oil pills against placebos and found no one more beneficial than the other.
This hasn’t stopped over-the-counter fish oil supplement brands from touting purported heart-healthy benefits on their bottles though. “Over 20 years ago, the U.S. Food and Drug Administration (FDA) approved a qualified health claim for fish oil that it may reduce the risk of coronary heart disease—but we didn’t have the trial data we now do,” says Ann Marie Navar, a cardiologist at UT Southwestern Medical Center in Texas.
She explains that the FDA stipulated at the time that its approval was based largely on observational studies and that randomized controlled trials were still needed. “Although subsequent large, well-conducted trials have since been done for omega-3 supplements and shown no benefit on cardiovascular events,” Navar says, “this outdated claim still hasn’t been re-reviewed by the FDA.”
An FDA spokesperson tells National Geographic that qualified health claims like this one means they were originally supported by scientific evidence but are not required to “meet the more rigorous ‘significant scientific agreement’ standard required for an authorized health claim.”
To prevent consumers from being misled about the level of science supporting a claim, the FDA official notes that “a qualified health claim is accompanied by a disclaimer or other qualifying language that describes the level of scientific evidence supporting the claim.”