I'll take the UV rays over a bunch of smelly, synthetic goop all over my skin. I also see people go from not seeing the sun in months to full, 1pm exposure for hours, then they get roasted, then they're in pain, then it takes weeks to heal, then they do it again. Or they'll start slathering on an absurd amount of sunscreen, the summer months go by, and they look just as sick and pasty and unhealthy as they did last year, as if they never went outside.

You've got to build intuition around how to get sun: what's your current skin tone, how much sun you've had recently, what it feels like to get an appropriate amount of sun vs. get burnt, the time of day, elevation considerations, whether you're going to be in the sun again tomorrow or all week after a lot of exposure today, if you're getting more direct sun on key areas like your neck and nose and ears, or whether you've got full body exposure. The more time in the sun, the more you understand how to behave, how to protect yourself, how to get what you need to feel good.

Most people pay no attention to how they feel day-to-day. They never learn what it feels like to eat a nutritiously dense meal, or what being fit feels like over the long term. It's the same with sun exposure: if you don't pay attention, you'll never learn.