Is Sunlight Exposure good for longevity?

The evidence is still emerging, so it's too early to say for certain. A widely discussed Swedish cohort study found that women who avoided sun exposure had higher all-cause mortality than those with high sun exposure, and a more recent UK Biobank analysis similarly found higher ultraviolet light exposure associated with lower mortality — provocative findings that run counter to standard sun-safety messaging, though they come from observational cohorts that cannot rule out confounding (people who avoid the sun may do so because they are already less healthy or less physically active). That's reflected in an evidence score of 20/100 for its role in overall longevity, drawn from 5 studies, with an estimated impact on longevity rated limited (25/100).