Sitting for hours has gotten a pretty bad rap of late, and by now most people know that a sedentary lifestyle leads to all sorts of health problems. But new research shows there’s at least one thing you can do during all that time off your feet that’s actually good for you: read a book.

A study published online July 18 in Social Science & Health shows that reading books has a significant relationship to increased lifespan.

A team of public health researchers from Yale University looked at data for 3,635 Americans over age 50 collected from 1992 to 2012. Adjusting for age, sex, race, education, wealth, marital status, and depression, they found that those who read books were more likely to live longer. Over 12 years of follow-up, book readers were 20% less likely to die than non-book readers. Overall, the researchers calculated that book reading was associated with an extra 23 months of survival.

Reading magazines or newspapers didn’t have the same effect.

The researchers found that people who read books showed stronger cognitive abilities, like recall and counting backwards—skills that, combined with reading, showed a positive relationship with living longer. Avni Bavishi, the master’s student who led the study, believes it’s the deep engagement required by the narrative and characters of fiction, and the length of both fiction and nonfiction books, that increases cognitive skills and therefore extends lives.

An important caveat is that the study only shows correlation, and not causation. In addition, there’s no way to be certain that the same correlations will prove to be there in younger populations, though Bavishi believes it’s likely.

In future studies, she says, it would be helpful to look more specifically at what kinds of books people are reading, and to look more closely at print, ebooks, and audiobooks to figure out if they have different relationships with longevity.