Hi everyone. Today I want to talk about the recently publicized announcement by the FDA regarding sunscreen labels.
Currently, we all talk about "SPF" levels, because that is the rubric provided by sunscreen companies that indicates how much protection sunscreen provides. "SPF" stands for "sun protection factor" and represents protection against UVB (ultraviolet B rays). While SPF indicators provide good information, the importance we place on them has given us a false sense of security that may, in some cases, indirectly lead to increased cases of skin cancer.
Ultraviolet light is divided into UVA, UVB, and UVC. UVC is the shortest of the three and is filtered out by the ozone layer. Although the ozone absorbs some UVB, much of the UVB reaches the earth's surface and causes sunburn and skin cancer. UVA is the longest of the three and "pound for pound" (or ray for ray in this case), UVA is much less cancer causing than UVB. However, much more UVA reaches the earth's surface than UVB, so UVA can also lead to skin cancer. The old adage was that UVB burns and UVA ages the skin. This is true to an extent, so sunscreen companies in the past always focused on UVB protection. However, studies have shown that UVA also causes skin cancer, so it is important for us, now that we know its dangers, to take action against it.
SPF is based on protection from UVB. A simple way of thinking of it is that if a person were to get sunburned in one minute, than the same person wearing SPF 30 sunscreen would get equally sunburned after 30 minutes of sun exposure. Because SPF has nothing to do with UVA protection, the FDA is now proposing rules that would force sun screen manufacturers to indicate their products' level of protection from UVA rays. Thus, the new rules would require easy-to-understand information that quickly informs them if a product has UVA and UVB protection, and if so, at what levels. In addition to the SPF number, sunscreens would have a one through four star rating of protection against UVA. Thus, a high SPF number and a four star UVA protection rating would provide the most protection. Also, the proposal would change SPF from sun protection factor to sunburn protection factor, making it clearer that SPF refers to protection from the "burning" UVB rays.
Many of the newer sunscreens brag about having broad UV protection or will specifically say that they provide UVA and UVB protection. It is important to note however that sunscreens cannot provide quality protection against UVA rays without several key ingredients. The most common ones are zinc oxide, titanium dioxide, avobenzone, parsol 1789, and mexoryl. I would encourage everyone to only use sunscreens that contain at least one of these ingredients so that you know you have UVA protection. Zinc and titanium are physical blockers that reflect sunlight from the skin, while the other ingredients protect the skin by absorbing the harmful rays.