Brain training games may not provide the benefits to brain health they claim to, according to experts.
Instead, a report from the Global Council on Brain Health recommends that people engage in stimulating activities such as learning a musical instrument, designing a quilt or gardening.
It said the younger a person started these activities, the better their brain function would be as they aged.
Age UK said it was never too late to learn something new.
The council - which is a collaboration of international scientists, health professionals and policy experts - has produced a report on the best ways to stimulate the brain and reduce cognitive decline.
It said that although many people thought playing online games, such as puzzles and mind games, designed to improve brain health was important, the evidence regarding the benefits was "weak to non-existent".
"If people play a 'brain game', they may get better at that game, but improvements in game performance have not yet been shown to convincingly result in improvements in people's daily cognitive abilities," the report said.
For example, there was no evidence that playing sudoku would help you manage your finances any better, it added.
Tai chi and photography
The report recommends seeking out new activities that challenge the way you think and are socially engaging, while leading a healthy lifestyle.
- practising tai chi
- researching your family tree
- photography classes
- learning new technologies
- creative writing
- art projects
James Goodwin, chief scientist at Age UK, which helped set up the Global Council on Brain Health, said brain decline was not inevitable.
He said: "There are plenty of activities that we can start today that can provide benefits for brain health, if they are new to you and require your concentrated attention.
"They may even be activities that you do regularly in your life, such as playing with grandchildren, gardening or playing cards.
"Even though it's never too late to learn something new, the overwhelming message from this report is that you shouldn't wait until later life to try to maintain your brain health."