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?

The last time I was at the hair cutting salon, the person who washed my hair asked me if I washed my hair everyday. I said I did, and she said she could tell. I'm not sure what she meant by this, but please tell me how she could determine this, and what is the best overall practice for washing hair in terms of frequency. I'm interested in the health of my hair as well as the health of my scalp. Thanks for you help!

How do I know if my hair is oily or dry? Does it make a difference if I'm a guy with short hair?

What are the reasons for getting white hair in teenagers?

My boyfriend and I have been together for almost three years, and we've lived together for more than one, but I still can't do Number Two when he's in the house. It's not a problem during the week when we both go to our separate jobs, but on the weekends, it's usually just the two of us in the house all day (and night) Saturday and Sunday and if I feel the need to poo, I have to wait until Monday. My question is this — are there any adverse health issues I should be concerned about with waiting to poo? I know that holding your pee can give you bladder infections, but is there a similar issue with Number Two?