Sunscreens are used to screen out ultraviolet light (UV) that is damaging to the skin. There are two types of UV light: UVA and UVB. UVA rays are responsible for causing skin cancer and premature aging and are the rays found in tanning beds. UVB rays cause skin cancer and “sunburns.” Recent studies have shown an increase in skin cancers (basal cell carcinoma and squamous cell carcinoma) in individuals under the age of 40. Improper use, or no use, of sunscreen and tanning behavior have played a large role in the increase of skin cancers found in this population.
In the past, “sun protection factor” (SPF) was based on protection from UVB rays. To determine the amount of sun you can get without a burn, you take the time you would normally burn in the sun without protection (generally, 20 minutes will produce redness on a light-skinned individual) and multiply the number with the SPF and divide by 60 to get the number of hours of sun protection it provides without sunburn. This is also dependent on repeat application of the product; every two hours being the recommended re-application time. As people vary and as the sun strength varies so will the sun protection of different products. UVA rays have been difficult to measure in the past but now there are ways to measure the protection which allows for a more defined “broad spectrum” sunscreen.
So, is an SPF 100 better than an SPF of 30? Data show that an SPF 15 will screen out about 93% of UVB rays and an SPF 30 screens 97%. There is minimal additional protection about SPF 30.
In June 2011, the Food and Drug Administration (FDA) adopted new labeling requirements for all sunscreens. The six main labeling requirements are as follows:
- Sunscreens may be labeled “broad spectrum” if they protect against UVA and UVB equally.
- Only broad spectrum sunscreens with SPF 15 or higher can state they reduce the risk of skin cancer and premature skin aging…IF USED AS DIRECTED ALONG WITH OTHER SUN PROTECTION MEASURES (limiting sun exposure during the peak hours of sunlight, wearing hats and protective clothing).
- Sunscreens that are SPF 2-14 OR any SPF that is NOT broad spectrum will be required to have a warning label stating that the product has NOT been shown to reduce the risk of skin cancer or premature aging.
- The terms “sunblock,” “sweat-proof,” and “waterproof” are no longer allowed on sunscreen labels.
- A sunscreen can use the word “water-resistant” but must specify whether it offers 40 minutes or 80 minutes of protection when swimming or sweating. Sunscreens that ARE NOT WATER-RESISTANT must include instructions to use a water-resistant sunscreen if swimming or sweating.
- Sunscreens CANNOT claim to provide sun protection for more than two hours without repeat application unless the manufacturer submits tests results to the contrary.
There are different components of sunscreens that make them UVA or UVB protective and can be found on the “ingredients” list on the back of the product. UVA protective ingredients include Avobenzone, Mexoryl, Zinc oxide, and Titanium dioxide. UVB protective ingredients include Octyl methoxycinnamate, Octyl salicylate, Octocrylene, Zinc oxide, and Titanium dioxide. Under the new regulations, any sunscreen that claims it is “broad spectrum” must contain a combination of the above ingredients. All of the above listed ingredients are considered “chemical” sunscreens except for Zinc oxide and Titanium dioxide. Zinc oxide and Titanium dioxide are considered “physical blocks” and are thicker than the chemical ingredients and have been “micronized” to make them more attractive. Many of them are tinted to reduce the “white” discoloration after application.
Some individuals have concerns over the safety of the ingredients in sunscreens. Janet Woodcock, MD (FDA director of the Center for Drug Evaluation and Research) acknowledged that the ingredients in the sunscreens available today have been in use for many years and there is no reason to believe that they are not safe for consumer use. It is generally believed that the benefits of sunscreen outweigh any risk that might be associated with prolonged use.
In addition to the FDA required labels, the Skin Cancer Foundation is also introducing a new labeling system classifying sunscreens as either “Daily Use” or “Active,” depending on their expected use. “Daily Use” sunscreens are used for protection of “incidental” sun exposure (i.e. driving, daily activities) and “Active” sunscreens are used for protection during extended sun exposure (i.e. athletic events, picnics). The Seal of Recommendation from the Skin Cancer Foundation will be based on specific scientific criteria that will verify a sunscreen’s UVA and UVB protective abilities. This process will be overseen by The Skin Cancer Foundation’s Photobiology Committee which is composed of dermatology experts in the study of the interaction between UV light and the skin.
Proper application of sunscreen is very important to get the maximum benefit of the product. Once an adequate sunscreen has been selected, application should begin before going outside. Apply 1-2 ounces of sunscreen to the body before going outside to allow it to absorb well and then apply every two hours to exposed skin after that…NO MATTER THE WEATHER. Makeup containing SPF is better than none at all but a more safe option would include applying a broad spectrum moisturizer with SPF of at least 15 prior to makeup application.
Other sun protective recommendations include sunglasses, hats, umbrellas, and wearing sun protective clothing made of UV protective fabrics that absorb UV light. For a quicker and less expensive way to get protective clothing, add a wash-in SPF product when doing the laundry.
So what’s on the horizon….oral sunscreens. There are several ingredients that are currently being evaluated that might allow sun protection if taken orally. These ingredients include ploypodium leukomotos (PL), found in a South American fern, grape seed extract, and ingenol mebutate found in radium weed native to the United Kingdom.
In summary, sunscreens have come a long way in the past several years. Two labeling systems for sunscreens will help consumers make more informed choices. The first labeling system required by the FDA is composed of guidelines which are much more specific and include sun protection factors for both UBA and UVB in addition to several other specific requirements.
The second labeling system was developed by the Skin Cancer Foundation and is not a requirement before going to market, but represents labels that are based on the products’ ability to meet very specific scientific criteria.
Take home message: The best sunscreen would have the new FDA labeling AND the seal of approval from The Skin Cancer Foundation!
– Sandra Morris, PA-C