Cosmetic Conundrums

Q: How much does a patient need to pay for an effective facial moisturizer?

Q: Do moisturizers remove wrinkles?

Q: Do sunscreens with an SPF above 15 provide better sun protection?

Notice that an SPF 4 sunscreen blocks 75 percent of the UVB radiation, but an SPF 15 sunscreen blocks 93 percent. This is a substantial improvement in photoprotection; however, the percent increase in UVB protection decreases as the SPF increases, so that an SPF 30 product only offers an additional 4 percent photoprotection beyond an SPF 15 product. Thus, dermatologists typically recommend SPF 15 sunscreens to combine product function with aesthetic characteristics, as higher SPF products tend to be sticky due to increased concentration of the sunscreen actives. Higher SPF products may provide value in patients with unique medical UVB photosensitive disorders.

It is important to remember that the single most common reason sunscreens fail to deliver their labeled SPF is due to incomplete film formation over the skin surface. This may be due to uneven application or to migration of the sunscreen over the skin surface. The sunscreen film typically begins to separate two hours after application. Thus, frequent reapplication of sunscreen products is essential to achieving sun protection once a product with an SPF of 15 or higher has been selected.