Anyone knows what rol sunscreen plays in vitamin D intake/generation by sunlight?
1. Uva is the cause of most skin cancer
2. Uvb generates vitamin d and sunburns
3. When uvb is present, you can make sufficient vitamin d quite quickly
This would suggest you would want sunscreen for longer exposures, or with much uva exposure. And could get vitamin d from a briefer exposure pre sunscreen.
I can’t say how completely sunscreen blocks vitamin d however.
I’d delete the above comment if I could. The main point that you can get vitamin d from short exposure without sunburn is correct, but I was incorrect on the risk. But he fact I was wrong about uvb and melanoma also makes me think I may be incorrect on the risk of uva during periods without uvb.
sunscreen either blocks, scatters, or absorbs those rays
seems to reason that sunscreen slows down sun burn and vitamin D3 production