[sooheon]

UVB exposure -> p53 activation -> downstream sex hormones upregulation is hypothesized to be mechanism, so sunscreen that blocks UVB will probably reduce the effect.

This study is part of an interesting trend I'm seeing of studies finding beneficial health effects to well timed, full spectrum sunlight exposure. The circadian benefits of seeing early morning sun every day (and darkness every evening) are well known. What's more surprising is that even UV exposure is not purely negative, and in the context of sunlight in moderate amounts (not to the point of acute sunburn) may be beneficial for health:

https://doi.org/10.1093/jnci/dji019 finds that high intermittent sun exposure actually decreases melanoma lethality. I.e. those who avoid the sun die more from melanoma.

https://doi.org/10.1111/joim.12251 found in a study that followed 30k women over 20 years that more sun exposure was associated with reduced all cause mortality. I.e. those who avoid the sun, apply more sunscreen die more in general.