Brain health and prevention — what the research actually says

Reviewed by the How To Help Your Elders medical review team

The supplement aisle will not save your parent's brain. The things that actually protect cognitive function are exercise, sleep, social connection, cardiovascular health, and a decent diet. These interventions are backed by decades of research from the NIH and the Alzheimer's Association. They are not expensive, not proprietary, and not mysterious, which is exactly why no one is marketing them to you at the drugstore.

The Supplement Aisle Is Built on Your Fear

Your mother is forgetting more things. You notice it when you call. She asks questions she asked two weeks ago. She cannot remember if she took her medications this morning. So you start looking. You want to do something, anything, that might help slow this down. You wander into the supplement aisle at the drugstore, and there is an explosion of possibility. Ginkgo biloba. Phosphatidylserine. Huperzine A. Brain-supporting formulas with names designed to inspire confidence. Bottles with soothing colors and cheerful testimonials from people who say they are sharper than ever.

You stand there, reading labels, looking at price tags, feeling the weight of wanting to help. The AARP reports that Americans spend more than $5.7 billion annually on memory supplements. That number grows every year, not because the products work, but because the fear works.

When your parent starts forgetting things, you become willing to try something. When the doctor says there is not much we can do yet, you keep looking. When you are scared, you buy. The supplement industry understands this at a fundamental level.

Most brain health supplements have thin evidence behind them. Ginkgo biloba has been studied more than most, and the results are underwhelming. The NIH-funded GEM trial, one of the largest studies ever conducted on ginkgo, found no evidence that it reduced the rate of cognitive decline or the incidence of dementia. Some smaller studies show a tiny benefit for memory or attention in healthy people. In people with actual cognitive decline or dementia, the evidence shows almost nothing.

Vitamin B12 and folate are a different story. These actually matter for brain health, but only if your parent is deficient. The CDC estimates that up to 15 percent of adults over 60 have low B12 levels. If your parent has normal levels, taking more will not sharpen their memory. It will just make their urine more expensive. If they are deficient, supplementing makes sense. Get the blood test first.

The FDA does not regulate supplements the way it regulates medications. A medication has to prove it works and is safe before it can be sold. A supplement can be sold first, and then the FDA has to prove it does not work or is unsafe before it can be removed from the market. You can market a supplement with impressive language about what it might do, and there is a reasonable chance no one will stop you.

What the Research Consistently Shows

If you look at the actual research on aging brains and cognitive decline, some things stand out because they keep appearing in study after study, the effect is consistent, and the research is good and reproducible.

Exercise matters more than any supplement on the market. The Alzheimer's Association identifies physical inactivity as one of the top modifiable risk factors for dementia. The NIH reports that regular physical activity improves blood flow to the brain, protects connections between brain cells, reduces inflammation, and improves mood, sleep, and blood pressure control. Walking matters. Strength training matters. Swimming matters. Dancing matters. What matters is that your parent is moving their body regularly, at a level that raises their heart rate, for at least 150 minutes a week.

The problem is that exercise is boring. It does not come in a bottle. You cannot decide to take it once and be done. You have to keep doing it, day after day, week after week. It costs less than supplements, which somehow makes it seem less valuable.

Sleep matters, and this is something many people get wrong. During sleep, the brain clears out metabolic waste products, consolidates memories, and performs maintenance that only happens when we are sleeping. The NIH has identified a system called the glymphatic system that flushes toxins from the brain during sleep, including amyloid-beta, the protein implicated in Alzheimer's disease. Poor sleep contributes to cognitive decline. Good sleep is protective. This means paying attention to sleep hygiene: keeping the bedroom cool and dark, maintaining a consistent sleep schedule, avoiding screens in the hour before bed, managing medications that interfere with sleep.

Social connection matters deeply. The CDC identifies social isolation as a risk factor for dementia, associated with about a 50 percent increased risk of developing the condition. People with strong social connections have better cognitive outcomes. The mechanism is not entirely clear. It may be that social connection provides mental stimulation, reduces stress, provides motivation to stay engaged, or all of these at once. For your parent, this means regular contact with people they care about. Conversation. Being known, and knowing others. If your parent is isolated, that is something worth working on, not with a supplement but with actual change to their daily life.

Diet matters, though less dramatically than the other factors. Mediterranean-style eating patterns, with lots of vegetables, olive oil, fish, whole grains, nuts, and legumes, are associated with better cognitive outcomes. The NIH-funded MIND diet study showed that people who followed the diet most closely had brains that functioned as if they were 7.5 years younger. But you do not need a special supplement version of this. You need actual food.

The Crossword Puzzle Myth

There is a persistent belief that keeping the brain active with puzzles protects it from decline. The evidence says that is not how brains work. Activities that are fun and engaging are good for general well-being, and they are worth doing for that reason. But doing a crossword puzzle does not prevent cognitive decline the way exercise does. Playing word games does not protect memory the way sleep does.

What does seem to help is learning something genuinely new and complex. Not more of the same type of puzzle your parent has always done, but something that requires building new skills and knowledge. Picking up a language, learning an instrument, taking up woodworking. These things may help more because they are harder and more complex. But the research is still developing, and it is hard to know if the benefit comes from the activity itself or from the fact that people who take up new challenges tend to be healthier overall.

There is nothing wrong with crosswords and puzzles. If your parent enjoys them, that is reason enough. Do not do them because you think they are preventing dementia. Do them because they are enjoyable. And do not substitute them for exercise, sleep, connection, and the other things that actually affect brain health.

Cardiovascular Health Is Brain Health

About 15 to 20 percent of the blood pumped by the heart goes to the brain. When blood vessels in the brain become damaged, when blood pressure is not controlled, when plaques build up and narrow the blood vessels, the brain suffers. The Alzheimer's Association reports that managing cardiovascular risk factors could prevent up to 40 percent of dementias worldwide, based on a landmark 2020 Lancet Commission report.

If you want to protect your parent's brain, you are really protecting their heart and blood vessels. Controlling blood pressure is at the top of that list. The NIH-funded SPRINT MIND trial showed that intensive blood pressure control (targeting systolic blood pressure below 120) significantly reduced the risk of mild cognitive impairment. Quitting smoking matters. Maintaining a healthy weight reduces strain on the cardiovascular system. Managing diabetes matters.

These are not flashy interventions. They are not supplements that come in bottles with inspiring names. But they do more for brain health than anything in the supplement aisle.

Sitting With the Hard Truth

Even if your parent does everything right, exercises regularly, sleeps well, stays socially engaged, maintains excellent cardiovascular health, eats well, they can still develop cognitive decline. You cannot prevent everything. Some people develop dementia despite doing everything right. Genetics matter. Luck matters.

What you can do is reduce risk. You can shift the odds in a healthier direction. You can slow decline in some cases. You can delay the onset of serious cognitive problems. But you cannot guarantee anything.

This is not a reason to do nothing. It is a reason to focus on the things that actually work, the things supported by good evidence. It is a reason to skip the expensive supplements with impressive marketing and focus on the basics: movement, sleep, connection, cardiovascular health, engagement with life.

When you are standing in the supplement aisle wondering what to buy, remember that the answer is not on those shelves. It is in the walking shoes in the closet. It is in the phone call you make to suggest dinner together. It is in the conversation with their doctor about whether their blood pressure is well controlled. The marketing wants you to believe that brain health is mysterious and requires special products. It does not. It requires attention, consistency, and effort. But it does not require spending money on things that probably do not work.

Frequently Asked Questions

Do brain supplements work for preventing dementia?
The NIH and Alzheimer's Association have found no strong evidence that any supplement prevents or slows dementia. The largest study on ginkgo biloba, the GEM trial, showed no benefit. The exception is correcting actual deficiencies: if your parent is low in B12, folate, or vitamin D, supplementing those specific nutrients to normal levels does matter.

How much exercise does my parent need for brain health?
The CDC and the Alzheimer's Association recommend at least 150 minutes per week of moderate-intensity aerobic activity, like brisk walking. Strength training two or more days per week adds additional benefit. The exercise does not need to be intense. Consistency matters more than intensity.

Can social isolation really increase dementia risk?
Yes. The CDC reports that social isolation is associated with about a 50 percent increased risk of dementia. The National Academies of Sciences has identified social isolation and loneliness as a serious public health concern for older adults. Regular meaningful contact with other people is one of the most protective things for an aging brain.

Is it too late to start lifestyle changes if my parent already has cognitive decline?
No. While the greatest benefit comes from lifelong habits, the Alzheimer's Association states that it is never too late to adopt healthier behaviors. Exercise, social engagement, better sleep, and cardiovascular management can help at any stage, though the benefits are more pronounced when started earlier.

What is the MIND diet and does it help?
The MIND diet combines elements of the Mediterranean and DASH diets, emphasizing green leafy vegetables, berries, nuts, whole grains, fish, poultry, olive oil, and beans. The NIH-funded MIND diet study found that people who followed it most closely had significantly slower cognitive decline. It does not require special products or supplements.

Should my parent get their blood pressure checked more often to protect their brain?
Yes. The NIH SPRINT MIND trial showed that intensive blood pressure management significantly reduced the risk of mild cognitive impairment. Regular monitoring and good blood pressure control are among the most effective things your parent can do for their brain health. Talk to their doctor about appropriate targets.