London: A daily crossword or Sudoku puzzle can help boost brain power and keep mind alert in old age, a new study has claimed.
Researchers reviewed studies on mental decline and said that most showed no strong evidence that physical exercise or taking vitamins or drug treatments helped keep the brain active, the Daily Express reported.
The team of researchers, who reviewed 32 trials involving about 25,000 patients, said that mental exercise in the form of a regular "brain-teaser" puzzle is the only proven method to boost brainpower as you age.
Lead author Dr Raza Naqvi, from the division of geriatric medicine at the University of Toronto, Canada, told the publication that mental exercise showed benefits in the three clinical trials in the review.
"This involved computerised training programmes or intensive one-on-one personal cognitive training in memory, reasoning or speed of processing," he said,
Naqvi said that in one trial, participants had significantly improved memory during five-year follow-up periods.
He said that another study showed an improvement in memory and attention in a group who took part in a computerised cognitive training programme.
The study was published in Canadian Medical Association Journal.