Brain & Mind
Power Brain
Sharpness, focus and a strong working memory.
Most of what genuinely sharpens thinking is unglamorous and free, and most of what is sold for it is neither.
What has real evidence
Sleep. Memory is consolidated overnight; a night lost is a day's learning weakened. Nothing on this page matters if this one is missing.
Aerobic exercise. One of the better-evidenced interventions for cognition across the lifespan, and it appears to protect against decline in later life.
Learning something difficult. The brain adapts to demand. A language, an instrument, a craft - the difficulty is the active ingredient, which is why puzzle apps you are already good at do very little.
Not being lonely. Social connection is a stronger predictor of cognitive health in later life than most people expect.
Attention is the whole of it. You cannot remember what you never properly attended to in the first place.
On brain supplements
The nootropic market is large and the evidence is thin. Omega-3 and B vitamins help people who are deficient in them and do very little for people who are not. If you want one intervention with a large effect on thinking, it is sleep, and it costs nothing.
Worth a doctor's attention
Memory trouble that is getting worse, that others have noticed, or that interferes with daily tasks. Some causes - thyroid disease, B12 deficiency, depression, medication side effects - are entirely reversible when found.
Worth having
Picked to go with what you have just read. We only list ordinary, widely available things.