Are Omega-3 Supplements Good for the Brain?

Note: The U.S. Food and Drug Administration (FDA) does not approve supplements for safety or effectiveness. Talk to a healthcare professional about whether a supplement is the right fit for your individual health and about any potential drug interactions or safety concerns.

“We have pretty good evidence on fish intake and its role in brain health,” says Puja Agarwal, PhD, a nutritional epidemiologist and an assistant professor of internal medicine at Rush University Medical Center in Chicago. “A higher fish intake is associated with a lower rate of memory decline over time as well as a lower risk of developing Alzheimer’s disease.”

It’s important to get enough omega-3s in your diet to help maintain and improve cognition and memory — and to know which sources are best.

Fish oil contains the omega-3 fatty acids EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Both are crucial for brain health because they’re key structural components of neuronal membranes, the outer boundary of nerve cells.

“Synaptic plasticity is how we learn new things, form memories, and recover from brain injuries,” Dr. Avena says. “Think of it like a path in a forest: When you walk it often, it becomes clearer and easier to follow (a stronger connection), but if you stop using it, it fades away (a weaker connection). This flexibility helps the brain stay sharp and adapt to new challenges.”

Research has shown that diets rich in omega-3 are healthy for your brain. But very little evidence proves that taking omega-3 supplements, including fish oil, can completely prevent or slow down conditions that involve cognitive decline.

Instead, researchers found vulnerable regions of their brains were using glucose less efficiently, says Rab Nawaz Khan, MD, a neurologist and brain health researcher with MyMigraineTeam. This inefficiency could increase the risk of synaptic injury and further cognitive decline.

“This study complicates the usual message that omega-3s are automatically good for the brain,” Dr. Khan says. Still, because this was an observational study and contained several limiting factors, it cannot definitively prove whether omega-3 supplements worsen cognitive decline, Khan says.

The results suggest there isn’t a one-size-fits-all recommendation when it comes to whether older adults should take omega-3 supplements.

Consuming fish oil won’t give you an instant “memory boost,” but Avena says omega-3s are important for brain health at any age. “The earlier you introduce them, the better.”

But the research is mixed in this area, says Natalie Rizzo, RD, the author of Planted Performance. “Some studies do show that supplementing with fish oil may prevent cognitive decline that comes with aging. Other studies suggest this isn't the case in a healthy population.”

Always talk to your doctor first before trying any new supplement — they can help you determine which are right for you and your risk for cognitive decline.

Will Extra Omega-3s Make Me Smarter?

While fish oil and omega-3-rich foods may help preserve cognition in some people, taking more than recommended will not make you smarter.

“Taking fish oil will not make you smarter or help you remember more if you already have an adequate intake [of omega-3s],” says Hussein Yassine, MD, a professor of neurology at the Keck School of Medicine in Los Angeles. “If you’re already at baseline, more is not going to be better. This is not an ‘intelligent pill,’ — you can’t take it and start remembering things,” he adds.

Most experts agree that the best way to get omega-3 fatty acids is by eating fatty fish, which contain the highest amounts of EPA and DHA. These fish include salmon, mackerel, and trout. “Whole fish provides additional nutrients and bioavailability advantages over supplements,” says Avena.

Research generally supports this recommendation. Most trials examining the health benefits of fish oil supplements have been inconclusive, Dr. Yassine says. “Fish is complex. Even the actual DHA and EPA in fish is not the same as what is present in supplements,” he adds.

How Much Omega-3s Should I Get?

But even if you’re only getting one serving of fish per week, the brain may benefit. “Research shows that when comparing people who are consuming one or more servings of fish per week to those who are eating less, fish eaters experience less cognitive decline over the years,” Dr. Agarwal says.

“That should be encouraging, because this is a simple lifestyle modification to maintain brain health,” Agarwal says.

Always talk to your doctor before adding fish oil or any new supplement to your routine. It’s possible supplements could negatively interact with prescription medications, leading to dangerous side effects.

According to Avena, other steps people can take to improve memory include:

• Get regular physical exercise, which boosts blood flow to the brain and supports cognitive function.
• Prioritize quality sleep, which is essential for memory consolidation.
• Spend time doing activities that promote mental stimulation, such as playing word games, puzzles, or learning new skills. These strengthen neural connections and enhance cognitive resilience.
• Seek social engagement and manage stress through activities like meditation or mindfulness. These also contribute to brain health.

“While no single activity is a magic bullet, a combination of these habits can have a significant positive impact on memory over time,” Avena says.

• Fish oil, found in fatty fish like salmon, mackerel, and trout, contains omega-3 fatty acids, which have a positive effect on brain health and may stave off cognitive decline and problems with memory.
• It’s preferable to get fish oil from your diet rather than from supplements.
• Talk to your doctor before starting to take fish oil supplements.
• Other ways to boost brain health and cognition include adequate sleep, exercise, and stress reduction.