I don't wear thongs very often, and when I do, it is not because I am avoiding "embarrassing visible panty lines." This is a ridiculous excuse for thongs. I wear them when I want to look and feel sexy- I often wear regular cotton or lace underwear underneath tight pants and shorts.
I also find thongs to be pretty uncomfortable. If I go a few consecutive days wearing only thongs, I hardly mind them at all, but the moment I pull on a pair of cotton or spandex panties, I feel so much better. It's easier to move around and my vagina can actually breathe!
In regard to my health, can thongs cause any vaginal infections or perhaps leave a permanent irritation along your anus? I haven't suffered from anything, but am wary of potential problems in case I start wearing them on a regular basis.