One of the things I love most about HN - you think of a hypothesis, and right after you see someone else who has already posted it. Very curious about this one

One of the things I love most about HN - you think of a hypothesis, and right after you see someone else who has already posted it. Very curious about this one as well. Though I don't imagine it being the "actual cause", just a big cofactor. I'd still put some money on the direct effect of sunlight absorption by your skin in itself having additional positive benefits (in appropriate doses).