The scientists divided the sample into three groups: those who read no books, those who read books for up to three-and-a-half hours a week, and those who read books for more than three-and-a-half hours.
The study, in the US journal Social Science & Medicine, found that book readers tended to be female, third-level-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. They found a similar, but weaker, association among those who read newspapers and periodicals.
“People who report as little as a half-hour a day of book reading had a significant survival advantage over those who did not read,” said the senior author, Becca R. Levy, a professor of epidemiology at Yale.