Habits That Protect the Brain After 50, and the Trials Behind Them
Most brain health advice comes from studies that watch people over time, which can show a link but not prove that a habit helps. A handful of large randomized trials have tested the advice directly. Some results are encouraging, some are disappointing, and together they make a sensible plan for anyone over 50.
The big picture
In 2024 the Lancet's standing commission on dementia, an international group of researchers, updated its list of risk factors that can be changed. There are now 14 of them, and the commission estimated that nearly half of dementia cases might in theory be prevented or delayed if all were dealt with:
| Risk factor | What you can do about it |
|---|---|
| High blood pressure | Check it at least yearly and treat it |
| Diabetes | Keep blood sugar in range |
| High LDL cholesterol | Get it measured; treat if your doctor advises |
| Hearing loss | Get tested; use hearing aids if you need them |
| Untreated vision loss | Yearly eye checks; cataract surgery when due |
| Physical inactivity | Move most days |
| Obesity | Steady, modest weight loss if overweight |
| Smoking | Stop, at any age |
| Heavy drinking | Cut back |
| Depression | Get it treated |
| Social isolation | Keep regular contact with people |
| Traumatic brain injury | Helmets, seat belts, fall-proofing at home |
| Air pollution | Hard to control alone; avoid heavy traffic air when you can |
| Less education | Set early in life, but learning new things later still helps |
"In theory" is doing a lot of work in that estimate. It assumes the links are causal and that everything could be fixed at once. Still, the list is a useful checklist, and most items on it are good for the heart too.
Blood pressure: the strongest trial result
If you only do one thing on this page, get your blood pressure checked and treated. The SPRINT MIND trial followed 9,361 adults with high blood pressure and compared two treatment goals: a top number under 120, or under 140.
New cases of mild cognitive impairment with two blood pressure goals
Cases per 1,000 person-years in the SPRINT MIND trial.
Show the data as a table
| Treatment goal | Cases per 1,000 person-years |
|---|---|
| Goal under 140 (standard) | 18.3 |
| Goal under 120 (intensive) | 14.6 |
The stricter goal cut the risk of mild cognitive impairment by about 19%. It also lowered probable dementia, from 8.6 to 7.2 cases per 1,000 person-years, though that difference wasn't statistically certain because the trial stopped early. The NIA's page on cognitive health singles out this result. Your own target should come from your doctor, since lower isn't right for everyone.
Combined lifestyle programs
Two large trials tested a package of habits at once rather than one at a time.
FINGER, Finland
The FINGER trial enrolled 1,260 older adults at higher risk of dementia. Half got two years of diet advice, exercise, brain training and regular checks on blood pressure and other heart risks. Thinking test scores improved in both groups, but more in the program group, by a small and statistically significant margin.
US POINTER, United States
The American follow-up, published in JAMA in 2025, enrolled 2,111 adults at risk of decline. Everyone got a lifestyle program. Half followed a structured, higher-intensity version, and the other half a self-guided one. Both groups improved on thinking tests. The structured group improved slightly faster, and the benefit looked larger for people who started with lower scores.
Source: Ngandu and colleagues, Lancet, 2015; US POINTER, JAMA, 2025
What I take from these two trials: the gains were small, they came from doing several ordinary things together, and structure helped. A walking group, a class or a regular check-in with someone may matter as much as the habit itself.
The MIND diet
The MIND diet blends the Mediterranean and DASH diets, with extra leafy greens and berries. Observational studies looked promising, so a three-year trial in the New England Journal of Medicine tested it directly in 604 older adults with a family history of dementia. Both groups were also asked to cut calories slightly.
Both groups improved on thinking tests, by about the same amount, and brain scans changed similarly. So the MIND diet did no better than a plain healthy diet with mild calorie cutting. I'd still eat that way: it's good for the heart and blood sugar. Just don't expect a specific brain benefit beyond eating well in general.
Hearing
Hearing loss is on the Lancet list, and treating it is simple. The large ACHIEVE trial of hearing aids in adults aged 70 to 84 found no difference in thinking decline over three years for the group as a whole, with a possible benefit in people already at higher risk. Hearing aids won't promise anything about dementia. They do make conversation, and staying social, much easier, and social isolation is on the list too.
Habits with good support from other studies
| Habit | Simple target | Why |
|---|---|---|
| Physical activity | About 150 minutes a week of moderate activity, plus strength and balance work | Lower risk of decline in many studies, and part of every successful lifestyle trial |
| Sleep | Seven to eight hours a night, as the NIA suggests | Poor sleep makes memory worse in the short term |
| Blood sugar | Keep diabetes under control | Diabetes damages small blood vessels in the brain |
| Alcohol | Limit it | Heavy drinking is on the Lancet list |
| Smoking | Stop | One of the 14 risk factors, and the payoff is wide |
| Social contact | Regular time with other people | Social isolation is a risk factor |
| Vision and hearing checks | Yearly, and treat problems | Both are on the list |
Where supplements fit
No supplement has the trial record of blood pressure control or the combined lifestyle programs. A few ingredients have encouraging small trials, saffron most of all, and some help with blood sugar, which matters for the brain. If you're considering one, read the research first. Our notes on saffron for memory and our Phytomem One review go through what's known and what isn't. Treat any supplement as an extra on top of the basics above, never instead of them.
Questions readers ask
What is the single best thing to do for brain health after 50?
Get your blood pressure checked and treated. In the SPRINT MIND trial, a stricter blood pressure goal lowered the risk of mild cognitive impairment by about 19%.
Does the MIND diet prevent dementia?
A three-year trial found the MIND diet did no better than a healthy diet with mild calorie restriction. It's a good way to eat, but there's no proof it protects the brain more than healthy eating in general.
Do brain games help?
Brain training was part of the FINGER program, which improved thinking scores slightly, but on their own puzzles and apps have weak evidence. Physical activity and social contact have stronger support.