Read Books, Live Longer? by Nicholas Bakalar.

Researchers used data on 3,635 people over 50 participating in a larger health study who had answered questions about reading. … [B]ook readers tended to be female, college-educated and in higher income groups. So researchers controlled for those factors as well as age, race, self-reported health, depression, employment and marital status.

Compared with those who did not read books, those who read for up to three and a half hours a week were 17 percent less likely to die over 12 years of follow-up, and those who read more than that were 23 percent less likely to die.

Book readers lived an average of almost two years longer than those who did not read at all.