The recent report of rising melanoma rates among women ages 19 to 35 sparked speculation that sunscreen use might be harmful because it allows people to stay in the sun longer than they otherwise would, thereby increasing their exposure to harmful UV rays. This study did not examine the causes of the increase in melanoma cases in young women, and there are other possible explanations, including unprotected outdoor tanning and use of indoor tanning beds. It would be unfortunate if these reports discouraged sunscreen use, because most recent research supports using sunscreen to decrease development of precancerous skin growths and many skin cancers and to prevent photoaging -- the accelerated aging changes seen in sun-exposed skin. For both health and beauty reasons, sunscreen use makes sense. However, sunscreen should be regarded as part of an overall strategy to protect the skin from too much UV light, including appropriate clothing (hats, sunglasses, T-shirts) and avoidance of too much sun exposure.
The most effective sunscreens block both UVB and UVA. UVB includes the shorter UV wavelengths that cause sunburn, DNA damage and skin cancer. UVA does not burn skin as quickly, but it penetrates deeper into the skin, damaging deeper structures and probably increasing skin cancer risk. There are many active sunscreen ingredients that effectively block UVB, including zinc oxide, titanium dioxide, octocrylene, homosalate and ensulizole. The level of protection from UVB is reflected in the SPF. The American Academy of Dermatology guidelines recommend an SPF of 15 or greater. I tell my patients to look for an SPF of 30 or more, since most people don't apply enough sunscreen to reach the SPF found on a product label.
Achieving good protection from UVA is a little trickier. Both zinc oxide and titanium dioxide provide protection against UVA, but zinc oxide provides broader spectrum protection. Avobenzone (which is mixed with other ingredients to prevent it from breaking down in sunlight) and ecamsule (or Mexoryl SX) are also good UVA blockers. Other ingredients that are used in Europe for UVA protection, such as Tinosorb S and Tinosorb M, are currently undergoing the FDA approval process. These products have the advantages of not breaking down in sunlight and not penetrating beyond the upper layers of the skin, minimizing concerns about side effects. Unfortunately, there is still no approved labeling system to describe UVA protection. Although the FDA did propose new labeling guidelines last year, they have not yet been finalized. Therefore, it is important to read labels to make sure that one of these UVA blockers is present in your sunscreen.
Another important issue concerns products that combine sunscreen and insect repellent. There are some studies that suggest that DEET, the most common insect repellent ingredient in these products, decreases the effectiveness of the sunscreen. There is also an issue with reapplication. Sunscreen needs to be reapplied after swimming, excessive sweating or every two hours when in the sun. This is often too frequent for a product that contains DEET, which may require waiting six hours before reapplication. As a result, in order to obtain adequate sun protection, it could be necessary to apply excessive amounts of insect repellent. Rather than this combination, it is better to buy two separate products and use each as needed.
One final note: I recommend creams or lotions rather than sprays. It is certainly easier to spray sunscreen on than to take a little more time to apply cream or lotion. However, it is difficult to apply spray on sunscreens evenly, and it is easy to miss areas. These products also should not be used on the face.
Here are some sunscreens I recommend: 1. Blue Lizard Baby and Sensitive Skin sunscreens SPF 30+,
2. California Baby sunscreen lotion SPF 30+,
3. Vanicream sunscreen Sport SPF 35 and Sensitive Skin SPF 30 ,
4. EltaMD UV physical sunscreen,
5. Olay Complete Defense Daily Moisturizer SPF 30,
6. Neutrogena Healthy Defense Facial Moisturizer SPF 45,
7. CVS Sunscreen with Zinc Oxide SPF 45.
