New Study Suggests the Best Strategy for Protecting Brain Health With Age

You may already know that exercise supports the brain, and you’ve likely seen stories about diets that help preserve cognition.

But new research points to a clearer answer: the most effective approach is not picking one or the other, but improving both together.

Why exercise and nutrition should be combined

Dementia affects more than 55 million people around the world, and because there is no cure, prevention has become a major focus for researchers, especially through lifestyle habits people can change.

Studied separately, exercise and nutrition programs have produced mixed findings. Some trials report benefits, while others do not, leaving scientists unsure whether either approach is strong enough on its own.

This new meta-analysis took a broader view. Researchers reviewed 14 randomized controlled trials involving more than 4,000 adults age 65 and older. In every trial, exercise was paired with dietary advice or nutritional supplements. Compared with control groups, the combined approach produced a statistically significant improvement in cognitive function.

Why the pairing appears to work better

So what makes the combination more effective than either intervention alone?

Exercise boosts neuroplasticity and increases blood flow to the brain. It also raises levels of brain-derived neurotrophic factor, or BDNF, a protein that plays an important role in memory and in maintaining neurons over time. Nutrition can strengthen those effects. Omega-3 fatty acids and Mediterranean-style eating patterns have both been linked to supporting BDNF expression and extending its brain-protective impact.

The muscle-brain connection may also help explain the results. During exercise, muscles release signaling proteins known as myokines. One of them, cathepsin B, can cross the blood-brain barrier and encourage BDNF production in the hippocampus, a region central to memory.

Because skeletal muscle is the main source of cathepsin B, preserving muscle through resistance training and enough protein becomes even more important with age.

Inflammation is another factor. Exercise causes contracting muscles to release interleukin-6, or IL-6. In this setting, IL-6 functions as an anti-inflammatory myokine and helps stimulate other anti-inflammatory mediators.

Dietary strategies, especially omega-3 supplementation and moderate calorie intake, may reduce inflammatory markers and reinforce the anti-inflammatory environment created by exercise.

What the studies actually examined

The trials in this meta-analysis used a wide range of methods, which makes the overall result more compelling because the benefit appeared across different approaches.

On the exercise side, the programs included resistance training, aerobic exercise, and multicomponent routines that combined strength, cardio, balance, and flexibility work. Frequency ranged from one to five sessions a week, and the interventions lasted anywhere from 12 weeks to four years.

On the nutrition side, some studies used dietary counseling based on the Mediterranean diet, the MIND diet, or national nutrition guidelines from Finland and Japan. Others relied on specific supplements, including omega-3 fatty acids such as DHA and EPA, vitamin D, protein, creatine, and HMB, a derivative of the amino acid leucine.

The variety suggests there is no single ideal formula. The key takeaway is that exercise and nutrition appear to work best when addressed together.

A small effect, but one that matters

To be clear, the numerical effect was not large. The meta-analysis found a standardized mean difference of 0.15 for overall cognitive function, which is statistically modest.

Still, the context is important. Cognitive decline tends to progress gradually with biological aging. A small positive effect may not mean a dramatic turnaround, but it can mean slower decline and better stability. Over many years, that can add up to preserved function, a later onset of dementia symptoms, and more time living independently.

In other words, exercise and nutrition are not a cure, but they may provide meaningful protection.

Practical changes that can build over time

The idea of modest gains having meaningful long-term value also applies when putting these findings into practice. The studies that showed benefits used realistic, scalable strategies. Evidence-backed options include:

• Add resistance training once or twice a week. Several trials relied on bodyweight movements and resistance bands, making them easy to do at home. Strength work helps maintain muscle, which supports the release of brain-protective myokines.
• Target 150 minutes of moderate aerobic activity each week. Walking counts. The FINGER trial, one of the best-known studies in this field, used personalized walking plans as its main aerobic intervention. Even people who already exercise may benefit from more movement throughout the day.
• Include omega-3-rich foods or consider supplements. Good dietary sources include fatty fish, walnuts, and flaxseeds. Some trials used DHA and EPA supplements to raise omega-3 intake.
• Follow Mediterranean or MIND diet principles. Both patterns emphasize vegetables, fruit, whole grains, legumes, fish, and olive oil while limiting red meat and processed foods. Perfect adherence is not necessary; small changes can still help.
• Focus on consistency rather than intensity. The interventions that worked were not extreme. They were sustainable, and that may be the most important brain-health lesson of all.

The takeaway

If you’ve been treating exercise and nutrition as separate wellness goals, this research suggests a better way to think about them. The brain benefits of lifestyle changes appear stronger when movement and nourishment are combined, not because one matters more than the other, but because they support the brain through different but complementary pathways.

The benefit is modest, but over time modest changes can make a real difference in how you think, function, and age.

Rather than trying to build the perfect routine, aim for practical habits you can keep up for years.