People with suntans don't look healthy, they look ignorant

UV exposure will give you cancer!

It's a government verified carcinogen, and if you voluntarily expose yourself to it in order to be "attractive," you need to re-evaluate your actions. Since summer's here, this fact needs to be emphasized towards people who are planning to sunbathe or otherwise tan. Skin cancer doesn't just happen to people who don't use tanning lotion, or people who get bad sunburns, or people with fair complexions, it happens to anybody who is exposed to too much ultraviolet radiation.

With this in mind, suntans no longer look attractive. That is, when I see somebody who is deeply tanned, I automatically think "Aha, a stupid person!", and any sexual attraction I may have had towards them goes away. People who do use sun block (SPF 20 or above is best) will be a normal color, and I can tell they care about themselves and their future, thus making them more attractive.

If this meme is spread, perhaps some day everybody will react to people who tan the same way I do, and they'll stop. Score four points for sanity, woohoo!

Lack of sun is a known risk factor for osteoporosis; skin makes vitamin D when exposed to sunlight and that is needed for making strong bones. There are suggestions that certain diseases like schizophrenia might be triggered by lack of vitamin D in the mother during pregnancy.

Little and often sounds like a good plan to me. Deep roasting your skin just causes a ton of genetic damage; and much of this is permanent. The medical recommendation I have seen is 10-15 minutes about 3x a week.

Incidentally, if you want a good tan, you're better off tanning at midday; contrary to popular opinion. The reason is that the highest levels of UV-B radiation happen within an hour or two of midday, it's the UV-B that makes you go brown the most; the UV-A you get the rest of the day only uncovers any tan you already have (and ages your skin 50x faster than UV-B does.) Also, the UV-B is the bit that generates vitamin-D in your skin, another big, big plus. However, it's the UV-B that triggers skin cancer and burning; so staying out for more than 10-15 minutes is really, really unwise.