I've been wondering about sunscreen's effectiveness in reducing cancer risk.
The general impression I've gotten in my (admittedly brief) research on it seems: "If you know you'll be exposed for a long duration in the summer/spring, then yes, wear sunscreen. Otherwise, Vitamin D generation takes priority." (related)
I've looked around on lesswrong, and can't find any really all-encompassing informative posts about it. The most interesting comment I've seen was by Tem42, who references a study that claims that overall cancer rates are actually lower in southern states vs northern states.
Is my general impression correct enough? Or should people be lathering sunscreen all the time; or not at all?
Thanks in advance!