How Does Sunscreen Work?

Sunscreen vs. Sunblock

There are two common commercially available sun protection lotions, those that absorb UV light (sunscreens) and those that reflect UV light (sunblocks).

Sunscreens absorb UV light through a chemical reaction which occurs within the skin after the lotion is applied. Whereas sunblocks reflect UV light do just that, they reflect the UV light away from the skin. The reflective sunblocks are commonly recommended by dermatologists and are most useful for the delicate areas of the body such as the lips, ears, and nose.

Both absorbing and reflecting sun protection lotions are available in water-resistant, waterproof, and hypoallergenic formulas. These formulas are most useful for infants, children, and active individuals who tend to play in the water and sweat more than others. A quality water-resistant or waterproof lotion resists water for approximately 40 to 80 minutes before needing to be reapplied.

Learn how to get the most out of your sunscreen.