I've been swimming a lot this summer and I have noticed a green tint to my blond hair. Is this caused by previous dyeing? Is it possible to remove the green tint? Thanks for your time.

I have dandruff that responds well to over-the-counter shampoo. Ergo, I have been using the stuff almost exclusively for ten years. No brand in particular, sometimes zinc pyrithione (the blue stuff!), sometimes coal tar (the smelly brown stuff!). Anytime I switch to non-dandruff shampoo for like three to four days straight, I get my dandruff back. I worry that I might be addicted to dandruff shampoo. Should I worry?

Ever since high school, I've had very oily hair and skin, but it became worse in college. Now I'm in my mid-twenties and have to shampoo my hair about 10 times each day to get it clean. Then by evening it's already oily again. This isn't my scalp trying to moisturize itself after being over cleaned, because I've tried not washing it completely and it's even oilier the next day.

Are there any special shampoos or medications that help reduce oily skin? I've tried some facial products from my dermatologist, but they haven't reduced the oil production. This is an embarrassing problem and limits the overnight activities I can do, like camping or staying with friends.

I was wondering what causes fingernails to turn yellow if you leave nail polish on for a long time. Is it bad? And what can you do about it?