Mayo Clinic researchers say reading a book, making a quilt or playing computer games delays the onset of dementia by a good margin.
The Mayo Clinic in Minnesota interviewed 200 people between 70 and 89 years old who had mild memory problems. Researchers then compared the results against another group who had no memory problems.
Researchers asked participants to explain their daily routines when they were between 50 and 65 years old.
The participants who were busy reading books, playing computer games or engaged in quilt making or knitting were found to have a 40 per cent reduced risk of memory impairment in their later years.
Those who watched TV for seven hours a day or less were 50 per cent more likely to develop memory loss compared to those who spent longer times staring at screens.
Study author and neuroscientist Dr. Yonas Geda told the audience at the American Academy of Neurology meeting:
"By simply engaging in cognitive exercise, you can protect against future memory loss. Of course, the challenge with this type of research is that we are relying on past memories of the participants, therefore we need to confirm these findings with additional research."
Sarah Day, head of public health at the Alzheimer's Society, is happy with the news. She told the BBC:
"One million people will develop dementia in the next 10 years so there is a desperate need to find ways to prevent dementia. Exercising and challenging your brain - by learning new skills, doing puzzles such as crosswords, and even learning a new language - can be fun.
But she wants more research done to see how effectively they reduce the risk of dementia.