I was thinking of buying a face powder that says it has an spf of 30. It seems convenient to have a powder sunblock since lotions make my oily face greasy. However, I was wondering if this powder will even be effective as a sunblock since I heard that some moisturizers and other products that advertise an added SPF sometimes don't have a high enough concentration of sunblocking ingredients to make it effective. I would like to know what do you think before I make my purchase.

I fell on my roller blades yesterday and skinned my knee. Now I'm watching my knee change and I am fascinated by the healing process. Could you explain to me just what is happening?

I plan to do some nude sunbathing this summer. What extra precautions should I take with the areas that have never seen the light of day? Should I use a higher SPF on my "naughty parts" than on, say, my arms and legs?

I am 21 and have had consistent acne. I have tried topical creams (benzoyl peroxide, Retin-A, and topical antibiotics; as well as oral antibiotics for a number of months before). But, the acne keeps coming back.

For acne, does taking omega-3 fish oil supplements help? If so, how does it help, for what length of time should it be taken, and how many milligrams should one take?