Can brain games prevent dementia? What the evidence allows us to say
No app, including Two5, has been shown to prevent or treat dementia. Health authorities do not treat commercial brain games as protection against Alzheimer’s disease. Some structured cognitive-training trials in older adults have improved the specific skills people practised, and guidelines allow that training may be offered because the evidence of risk reduction is low and uncertain. That is a research finding about defined training, not a reason to buy or play a game as medicine.
Published 2026-10-27
The claim, and the answer
“Brain games prevent dementia” treats a hobby, a product, and a disease outcome as one thing. They are not. Dementia is a clinical syndrome with many causes. Alzheimer’s disease is the most common cause of dementia in older adults. Preventing it would mean fewer people develop the disease, shown in proper studies — not a higher score on a puzzle.
The National Institute on Aging tells readers to be wary of claims that computer or online games improve memory and thinking, because commercial programs have not been shown to match the effects seen in cognitive-training trials. The World Health Organization’s 2019 recommendation on cognitive training is conditional and based on very low to low quality evidence. It is about offering training to older adults with normal cognition or mild cognitive impairment. It is not a consumer-app endorsement, and it sits next to stronger advice on things like physical activity, tobacco, and blood pressure.
What a study would have to show
A prevention claim needs a defined group of people, a defined activity, a comparison group, enough time, and an outcome that is the disease or a validated clinical measure — not only “got better at the game.” Observational studies that find puzzle players have lower risk can be useful signals. People who do puzzles may also differ in education, health, and social life. Those studies do not prove the puzzles caused the difference.
Near transfer (better at the trained task) can be real and still say nothing about dementia. Far transfer to daily function is a higher bar. A clinical outcome, years later, is a higher bar again. The February 2026 NIH note is about one ACTIVE protocol: speed-of-processing training plus later booster sessions, and later diagnosis codes in Medicare data. Speed training without boosters, and the memory and reasoning arms, did not show the same association. It does not show that puzzles, memory apps, or Two5 prevent dementia.
What to do with worry about memory
Forgetting a name occasionally is common. A change that interferes with daily life is a reason to talk to a doctor, not a reason to download a game and wait. Two5 will not label anyone as impaired from a score, and this website does not collect health information on the waitlist.
Enjoying hard problems is a good enough reason to want Two5. Protection from dementia is not a reason we can honestly offer.
Sources
On Two5
If you came here for a medical answer: brain games are not a prevention program, and Two5 is not enrolling patients. The pages below explain the product and the evidence rule. A waitlist link is on this page only so it is not confused with a study.