After a hemorrhagic stroke—in which a blood vessel ruptures in the brain—32-year-old Kelly Fucheck changed her diet to restore her overall physical and mental health. Now 46, she and her family eat plenty of fruits, vegetables, whole grains, and lean protein—and Fucheck fits in fish, nuts, and seeds packed with omega-3 fatty acids, sometimes in surprising ways.

“Chia seeds are a good source of omega-3s, but my kids wouldn’t eat them,” says Fucheck, co-owner with her husband of Industrious Spring gym in Spring, TX, and the mother of a son, 17, and daughter, 11. She found a way around her kids’ aversion, though: soaking the seeds and blending them into spaghetti sauce or smoothies. “They don’t notice them,” she says.

Foods rich in omega-3s may be associated with a lower risk for dementia, depression, certain ischemic strokes, and diminishing memory skills, according to recent research. Studies also suggest an association between omega-3 consumption and a slight reduction in the risk or severity of Parkinson’s disease, although a review by researchers published in Clinical Nutrition Open Science in June 2024 concluded that while the evidence sounds promising, more research is needed.

The story is similar for multiple sclerosis; a Kaiser Permanente Southern California study published in October 2021 in the journal Multiple Sclerosis found that regular consumption of seafood and fish oil was associated with a lower risk of developing MS, but it noted that more studies are needed. Brain researchers say omega-3s—the docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) found in fish in particular—may inhibit inflammation, prevent blood clots, and reduce elevated blood pressure as well as keep blood vessels in the brain and body pliable. But experts say focusing on these good fats alone is misleading.

Other Factors at Play

Plenty of diet and health population studies—those that ask large groups of people to track what they eat and then monitor their health over time—suggest brain benefits for foods packed with omega-3s. But well-designed, randomized controlled trials—in which participants take set amounts of omega-3s (usually as fish oil capsules) and researchers check for specific brain outcomes—haven’t backed up the claims, says David Knopman, MD, FAAN, professor of neurology at the Mayo Clinic in Rochester, MN.

“While there is pretty good epidemiological evidence for an association between fish consumption and reduced risks of incident dementia, it is fundamentally wrong to assume automatically that the link is due to omega-3s,” he says. “More affluent people eat more fish. Socioeconomic status has a very strong relationship to all aspects of disease, including diseases of the brain.… Eating more fish may also mean you’re eating less of something else, like chips and beef jerky.”

It’s also not clear that omega-3s are the only source of brain benefits found for fish in population studies, says Giuseppe Grosso, MD, PhD, professor of human nutrition at the University of Catania in Italy. In a recent meta-analysis of 35 studies, published in Aging Clinical and Experimental Research in August 2024, Dr. Grosso and his team found that people who ate more fish had a lower dementia risk.

“Factors other than fatty acids have been lately considered important mediators of the healthfulness associated with fish consumption,” Dr. Grosso said by email. Preclinical studies have shown that specific oligopeptides—small proteic structures composed of a few amino acids—exert antioxidant and anti-inflammatory action, support the health of blood vessels, and promote neuroprotective effects, he adds.

Fish also provides selenium and vitamin D, which discourage inflammation, regulate blood pressure, and guard against plaque buildup. This may help prevent blood vessel damage in the brain that can contribute to nerve-fiber degeneration and loss of brain tissue, according to French researchers. Nuts, meanwhile, deliver fiber, B vitamins, cell-protecting chemical compounds found in plants, and several types of good fats that can benefit the brain. They also are associated with better thinking and memory, according to a report in the journal Nutrients.

These foods don’t act alone. An overall healthy diet like the Mediterranean or MIND (Mediterranean-DASH Intervention for Neurodegenerative Delay) diets may offer stronger brain protection by keeping blood vessels healthier, tamping down inflammation, and neutralizing compounds called free radicals that can damage brain cells. The Mediterranean diet focuses on fruits, vegetables, whole grains, fish, and legumes while limiting foods high in saturated fat and sugar. Following the MIND diet, meanwhile, involves consuming at least three servings of whole grains, a salad, another vegetable, and a glass of wine daily; beans and legumes every other day; berries and poultry at least twice weekly; and a type of fish at least once weekly.

Dr. Knopman recommends that people also engage in regular physical activity, get high-quality sleep; not smoke; and control their blood pressure, cholesterol, and diabetes.

Fitting in Omega-3 Rich Foods

Registered dietitians offer these recommendations for fitting more foods rich in omega-3s into your diet.

Have fish twice a week. The American Heart Association and the American Stroke Association recommend aiming for two 3-ounce servings of fish a week—especially fatty, cold-water fish higher in omega-3s like salmon, sardines, mackerel, anchovies, herring, and bluefin tuna. But in some large studies, people who ate any kind of fish also reported a lower risk for dementia, so don’t rule out lower-fat types like cod, tilapia, and flounder, says Kristin Gustashaw, MS, RDN, LDN, a registered dietitian, nutritionist, and advanced-level clinical dietitian at Rush University Medical Center in Chicago. These provide some amount of omega-3s, as do shrimp, scallops, and lobster.

Consider budget-friendly fish. “Canned fish is a great option if you are watching your bottom line,” says registered dietitian nutritionist Amy Bragagnini, MS, RD, CSO, a clinical dietitian at Trinity Health Richard J. Lacks Cancer Center in Grand Rapids, MI, and a spokesperson for the Academy of Nutrition and Dietetics. “You can chop anchovies and add them to a spicy tomato-based pasta dish or add canned tuna to a Mediterranean salad. Canned fish is also shelf-stable, which makes it a great addition to your pantry.

“Another economical way to shop for fish is to buy frozen,” Bragagnini says. “I tend to keep an eye out for the best local sales and then stock up on a variety of frozen fish like cod, swordfish, salmon, or mackerel. I simply take a few portions out of the freezer the night before and thaw them in the refrigerator overnight.”

Include plant-based omega-3s. For individuals who follow plant-based, vegetarian, or vegan diets devoid of fish, there are additional ways to consume plant-based omega-3s. Ground flaxseed, flaxseed oil, ground chia seeds, soybeans (like edamame), soybean oil, walnuts, and canola oil are good sources of alpha-linolenic acid (ALA), which your body converts into DHA and EPA. “Nutrients are absorbed better from ground flax and chia than from whole seeds,” Gustashaw says. “I add them to salad dressings, soups, stews, chili, and hot breakfast cereals. Buy them in small quantities and store in the refrigerator, following label directions, to keep them fresh.”

Drizzling flaxseed oil on salads or vegetables or using it in sauces or dips works well, too. “You should not use flaxseed oil to cook at high temperatures, given its low smoke point,” Bragagnini says.

And savor a handful of walnuts, instead of chips, for a snack. “Nuts are satisfying and full of nutrients but contain a lot of calories, so stick with one serving,” she says. A palm-sized amount—about a quarter cup—of 14 English walnuts has 185 calories. A quarter cup of black walnuts, also a source of ALA, has 170 calories.

Try other sources. If you don’t like fish or nuts, you can also try fortified eggs, yogurt, juices, milk, and soy-based drinks for some omega-3s.