I never wore much growing up, or even in my twenties. When I was ~30, I met my buddy who was ~37, and a sun worshipper for most of his life. When he turned 40, he told me the one thing he regretted more than anything was (as a blonde-haired, blue-eyed person of european descent) not wearing sunblock. When I asked him why, he pointed out that the crows feet around his eyes were more from being such a sun freak in his twenties, more than from age. And looking at him, I realized that he had the facial wrinkles of a man 10+ years older than he was.
I now wear spf50 most of the time, especially as I work outside quite a bit. If I'm not going to be out all day, I might downgrade to spf35 for the shorter term. The other reason why I do this is because my sister (who, like me, is a redhead with freckles and lighter colored eyes [hers are hazel, mine are blue]) has been fighting melanoma cancer for the past year or so. Hers is also related to a depressed immune system (from battling rheumatoid cancer), but I'm seeing what she's going through right now, and really don't wish to go through that myself.
Oh, and anyone who believes that sunblock causes skin cancer seriously needs to go visit Snopes website every so often, to get their BS level knocked down!! :roll: