Names take a second longer to arrive. You walk into a room and forget why. Somewhere past fifty that stops being a joke and becomes a question. The line is simpler than it feels. Forgetting a name and getting it later, or fumbling a word now and then, sits on the normal side of the Alzheimer's Association's warning-signs list, a guide for families rather than research. Evidence: decent Memory trouble that gets in the way of daily life, getting lost somewhere familiar, or people close to you noticing it's worse over months: that's a doctor visit. Depression, thyroid problems, low vitamin B12, heavy drinking and some medicines can all cause memory trouble that improves once treated. Evidence: solid
Some of the risk can be changed. In 2024 an expert panel writing in The Lancet counted 14 risk factors for dementia that can in principle be changed, adding vision loss and high LDL cholesterol, the harmful kind, to a list that already had hearing loss. Dealing with all of them could prevent or delay about 45 per cent of cases across a population. Evidence: decent That's a figure for whole countries, not your personal odds. Muscle counts too: in a 2025 review, the 9 small trials that measured overall thinking, 517 older adults in all, found resistance training, working muscles against a load, improved scores modestly, though the range of likely effects was wide. Evidence: decent
Three things get oversold. Ginkgo: in a large trial, 3,069 people 75 and over took it or a dummy pill for about six years, and it didn't reduce dementia. Evidence: solid Testosterone: the big recent trial, TRAVERSE, gave it to men with confirmed low levels and heart disease or a high risk of it. It did no worse than a dummy treatment on serious heart events, but brought more irregular heartbeat, kidney injury and blood clots in the lungs. Evidence: decent It wasn't a trial of memory. One that was gave older men with low levels a year of testosterone or a dummy gel, and memory didn't improve. Evidence: decent And the line that you lose so many brain cells a day after a certain age: careful counts find few neurons die in normal ageing, not enough to explain the slowing. Treat the daily number as a myth. Evidence: decent
Normal, or a doctor
Know the line, and go early if you've crossed it. Some causes are treatable, which is the point of going. Evidence: solid Confusion that comes on suddenly is different: that's an emergency, not a booking. Call your local emergency number (112 in the EU). Evidence: solid
Memory and learning
Memory getting worse? Know when it's a doctor
A name that comes back later is normal. Getting lost somewhere familiar, or people close to you noticing it's worse over months: book a doctor. Sudden confusion: emergency, now.
10 minEvidence: decent
Mood
Two questions, then a doctor
Ask yourself about the last two weeks. Little interest or pleasure in doing things? Feeling down, depressed or hopeless? Yes to either on most days: book a doctor.
2 minEvidence: decent
Ears, eyes, blood pressure
Three risk factors a doctor can measure. The hearing and blood-pressure results come from trials, the eye result from a long observational study, and none of them shows that fixing it prevents dementia. Evidence: decent The hearing trial's well-known 48% comes from a higher-risk subgroup; across everyone it found no effect. Evidence: decent
Memory and learning
Get your hearing checked
Missing words in conversation, or turning the TV up? Ask your doctor for a hearing test. If aids are offered, wear them.
10 minEvidence: decent
Memory and learning
Get your eyes checked
Sight got worse, or no eye test in years? Book one. If they find a cataract, ask your eye doctor whether and when to remove it.
10 minEvidence: decent
Memory and learning
Know your blood pressure number
Get your blood pressure measured this month and write the top number down. If it's high, ask your doctor what your target should be.
10 minEvidence: decent
Keep moving, keep using it
This is the slow part, the habits linked to cognitive reserve: how much wear a brain can take before it shows. When work ends, replace the role and the people, not just the hours.
A note on lifting. The lifting hack's own trials measured low mood, not memory. Evidence: decent For thinking, the evidence is the 2025 review above: in 9 trials of healthy people over 60, 517 in all, resistance training lifted overall thinking scores by a modest amount, and the range of likely effects ran from almost nothing to fairly large. Evidence: decent Nobody has shown it prevents dementia. Evidence: decent
Body
Walk three times a week
Forty minutes, brisk enough to notice your breathing, three times a week.
40 min, 3x a weekEvidence: decent
Body
Lift twice a week
Two sessions a week. Squats, push-ups, rows, with whatever weight you have, until the last few reps are hard. Add load slowly.
2 sessions a weekEvidence: decent
Memory and learning
Pick one hard skill, not five easy ones
Choose one thing you're bad at and want. Instrument, language, a sport, a craft. Three months, several hours a week. Then judge.
5–15 hours a weekEvidence: decent
Purpose
Book a standing shift, not a favour
In the first month after a role ends, sign up for one weekly shift somewhere that will notice if you don't turn up. A rota, not a favour.
2 hours a weekEvidence: decent
Friends
Add a friend at the big changes
New job, a move, a baby, retirement. In the first three months, pick one person from the new setting and suggest something specific. Then again a fortnight later.
10 minEvidence: worth trying
Skip the shortcuts
A pill or an app is easier than any of the above. Neither has the evidence. Evidence: solid
Memory and learning
Skip the ginkgo
Taking ginkgo to protect your memory? Stop buying it. In a large, long trial it didn't reduce dementia.
no timeEvidence: solid
Memory and learning
Delete the brain-training app
If the goal is a sharper head, swap the app time for a real skill. The app makes you better at the app.
no timeEvidence: solid