An alternative explanation for the finding is that high IQ people are more likely to have mentally stimulating work and can lose more of their mental capacity without appearing demented.<p>You can't easily change peoples' jobs, but you could do a randomized trial where the treatment group is encouraged to take up a mentally stimulating hobby, say
Scrabble, chess or bridge. It would be great if taking up such a hobby staved
off dementia, but I am skeptical that it does.<p>'Researchers have found that the more people use their brains at work, the better they seem to be protected against thinking and memory problems that come with older age.<p>In a study of more than 7,000 Norwegians in 305 occupations, those who held the least mentally demanding jobs had a 66% greater risk of mild cognitive impairment, and a 31% greater risk of dementia, after the age of 70 compared with those in the most mentally taxing roles.<p>“It really shows how important work is,” said Dr Trine Edwin, a geriatrician and postdoctoral fellow at Oslo university hospital. “It’s important to go to work and use your brain, and to use your brain to learn new things.”'