I am quite confused as to whether oily types prone to blackheads such as myself should avoid zinc oxide. Paula says as much and recommends avobenzone-based sunscreens instead. Dr. B. doesn't address that particular issue in her book, but does recommend physical blocks containing zinc oxide or titanium dioxide for oily, sensitive types because avobenzone stings. Additionally, the Acne Detective website (www.zerozits.com/Articles/acnedetect.htm#inglist) indicates that zinc oxide is noncomedogenic.

I normally have teflon-tough skin but have a preference for physical blocks because they don't take as long to work (versus the 30 minutes avobenzone needs after application) AND they don't stain the necks of my white t-shirts yellow! However, now that I've started using Retin-A, avobenzone stings a bit right after application. It's nothing I couldn't live with but is another plus for physical blocks, in my opinion.

I guess I'm worried that if I use zinc oxide, if it DOES clog pores, will negate any effects that the Retin-A would have, and I'll see no benefit from the Retin-A.

Any thoughts?