A popular belief states that applying an SPF product with a high SPF factor (30 ), and reapplying it regularly, will keep you completely safe from ultraviolet-induced sun damage, whether from UVA or UVB rays. Is this myth true or false? The determining factor is the type of sunlight you are exposed to.

The truth: First, SPF terminology is primarily a measure of UVB protection, and does not apply to UVA rays. Furthermore, most ingredients used in SPF products available on the U.S. market do not block the entire ultraviolet spectrum. SPF filters work in one of two ways: they either absorb UVAs (320 to 400 nm) and UVBs (290 to 320 nm), or they reflect these nefarious rays. The more popular metallic ingredients such as zinc or titanium are examples of ingredients that facilitate the reflection of light. Zinc protects from rays ranging from 290 to 380 nm, whereas titanium protects from rays ranging form 290 to 340 nm. Neither protect from the 380 to 400 nm range (UVA rays). The solution: always complement SPF protection (which, let's be clear, is absolutely essential) with antioxidant protection (Day 25). Wear a hat, avoid sun exposure between 10 and 4, and don't forget incidental some from driving, in your home, and doing daily errands. And you must reapply not matter what SPF you have on if you are in direct sun.

Many make-up foundations have SPF included in the ingredients. While that is an important component, it is not enough to protect yourself all day while in direct sunlight. It is also not enough to protect you while driving during the most intense part of the day. We see many women in our salon who have pigmentation (age spots) from unprotected and prolonged exposure to the sun's damaging rays. By using products that contain high enough and the correct type of SPF protection you can minimize the damage. While there are treatments to correct pigmentation, avoiding the issue is always the best course of action.

Melanie Vasseur is a chemist, esthetician and the founder of Vasseur Skincare. For more skin care tips and information, visit Vasseur Skincare at www.vsskin.com. (619-236-9095)