How often old people read a newspaper, play chess, or engage in other mentally stimulating activities is related to risk of developing Alzheimer’s disease, according to a study published June 27, 2007, in the online edition of Neurology® ... The study found a cognitively active person in old age was 2.6 times less likely to develop dementia and Alzheimer’s disease than a cognitively inactive person in old age,- says research by the American Academy of Neurology.
Now, I have some personal experience witnessing Alzheimer's at work. My Grandfather suffered from the disease for his final few years. Although perhaps "suffered" isn't the right word, at least for his case. He would frequently pleasantly hallucinate during this period of life, telling us for instance on the phone how he'd just got back from bowling for Norfolk County at cricket, albeit underarm. And he never had to face his own mortality, which is perhaps an existential blessing of sorts, a blessing of innocence. Perhaps. Perhaps not.
He never played chess though. Anyway, I don't think anyone knows if Alzheimer's is inherited or not - so I think I just found another reason to continue playing chess for the rest of my life.