Considering that Honolulu has an average of 278 sunny days a year, it may come as a surprise that the city is good for your skin. "But pollution levels are very low," explains Levine. Indeed, Honolulu has the lowest rate of pollution in Hawaii and zero high-ozone days. The humidity levels can also benefit dry skin. Plus, the ample sunshine means that residents are diligent about sun protection. If you're visiting, remember to wear sunscreen, warns Levine. One with at least SPF 30 is your best bet.