However, during the winter it is really good for you regardless of penis due to Vit. D. Not getting enough sunlight will make you feel like poo. Tanning is supposed to kill that.
I'm currently on 50,000 IUs a week due to lack of Vitamin D and sunlight DEF. makes me feel a lot better.
Just saying... Right on to penis' that tan, I personally respect you. I thought it was gay for guys to tan up until recently. Now I know how important it is.
When the weather is right, and it always is, i like to strip down nekkid and lounge in the pool for a while or go down to the creek/river and strip down and swim...no artificial light, sprays, or what-have-ya