The SPF controversy is one that is batted around by numerous so-called and self-proclaimed authorities on the subject, such as social-media bloggers and “naturalists” and the true experts on the subject like health educators and medical professionals like myself. The confusion exists because the media and skincare arena inundate the public with numerous discussions and debates, mixed with misinformation and ignorance, about how adequate SPF is defined and what an adequate amount of protection in sunscreen is. These mistruths drive me absolutely insane. There are so many of these exaggerations and misinterpretations that the real truth is often lost in the shuffle. Not only has social media taken a dominant hold of skincare education, which is certainly and completely absurd, but also the average consumer often mistakes this information as the expert gospel and true reality. More often than not, the “facts” are extracted and extrapolated from “lay” resources and opinion mongers, frequently driven by industry and financial gain. But what exactly is SPF and what is the medical truth about sunscreen? The answer is not always straightforward or easy. Let me tell you how and why.
The SPF denotation on sunscreen packaging actually is an acronym for Sun Protection Factor and is defined as the theoretical amount of time one can remain out in sun without getting burned. The SPF measures specifically the UVB protection and gives it a number. In other words, the SPF ratings reflect the extent of protection against only UVB rays. On the other hand, UVA protection is either all or nothing, specified on sunscreen packaging as simply “broad-spectrum.” What is scary is that UVA rays are not filtered out by the ozone layer or our earth’s environment. It is literally everywhere during daylight. It also penetrates glass, like the windshield. And it is the dominant UV ray in tanning booths. Since, like UVB, it causes skin cancer, most notably the life-threatening melanoma, and photoaging as well, it is vitally important that your sunscreen’s label states “broad spectrum” (in addition to the SPF designation) on its packaging to protect you against these UVA rays. If it doesn’t say “broad spectrum,” you’re still vulnerable to UVA damage, which can be subtle and insidious.
Let’s talk UVB now, and break down what SPF means. Remember that SPF, or Sun Protection Factor, is what protects you from the UVB rays, the main burn rays that cause skin cancer. So an SPF of 15 is defined as one’s being able to be out in the sun 15 times longer without being burned. Of course, this number is only theory, based on laboratory tests in the most ideal and compliant conditions in a research setting. Plus not everyone’s skin is the same. Multiple factors enter into determining skin type, which in turn determines what is “normal” or “expected” for a specific individual’s skin, which in turn may determine the SPF number and ideal use of sunscreen in any given environmental situation. A standard SPF for “all humans” is an averaging of sorts, but cannot and should not be universally determined across the board in real life terms. Although an SPF of 30 may be appropriate for “most humans” in “usual” environmental conditions, for example, an SPF of 30 on a very fair person hiking in Australia on vacation may not be enough to prevent burning quickly and may not demonstrate the theoretical SPF 30 found in the lab. Just as medication doses have a range of safety and efficacy, where an appropriate dose for one individual may not be appropriate for another. Likewise in regards to SPF, it should be determined on an individual and unique basis, taking into account the skin type, medical history, preexisting skin conditions or diseases, UV environment, geography, and lifestyle. That’s where your dermatologist’s input may become invaluable advice for sunscreen selection and guidelines for your use.
Dermatologists utilize a numerical scale called the Fitzpatrick Skin Typing Test or Scale to determine human skin color and its clinical response to ultraviolet light or sun. Developed in the 1970’s by Dr. Thomas Fitzpatrick, a pioneer and expert in modern dermatology to aid in clinical skin classification, this scale is absolutely not an indicator of race or ethnicity at all. It most importantly takes into account the skin’s tendency to burn in the sun and also takes into account one’s eye color and native hair color. And as our melting pot gets more and more “melty,” the skin type gets more and more difficult and challenging to assess. The skin color you see isn’t necessarily predictable in how it responds on a clinical level because of this melding or “melting” of different ethnicities in one individual. Most recently, in this cosmetic age of Botox, dermal fillers, and lasers, the Fitzpatrick Scale has gained tremendous clinical applicability because of its bearing on choosing appropriate cosmetic treatments for the skin type. It also helps in determining treatment potency and predicting clinical and healing responses to a particular procedure. The six Fitzpatrick types on a very rudimental level are as follows:
- Type I always burns, never tans
- Type II usually burns, tans minimally
- Type III sometimes mildly burns, tans uniformly
- Type IV burns minimally, always tans well
- Type V very rarely burns, tans very easily
- Type VI never burns, never tans
So why am I going into such excruciating minutia about this Fitzpatrick Skin Typing you may ask? Well, for one, it shows how detailed and specific skin types can be in terms of burning tendency, which translates to clinical response to various treatments, treatment outcomes, and sunscreen needs. And the second is that I am a bit of a nerd and enjoy sharing information like this. And of course, lastly, it demonstrates that one size does not fit all.
Another controversy that confronts me often is the Vitamin-D-deficiency issue. It is true that many of us living in a relatively non-sunny climate like Michigan may develop significant depletion of our Vitamin D stores. Plus, having this deficiency tremendously affects our bone density, immune health, cardiovascular fitness, and cancer risk. However, blaming it on overuse of sunscreen and SPF are dangerous statements to make because there is really no real truth or clinical validity to these blame claims. The incidence of skin cancer is rising globally every year, including the deadly and dreaded melanoma, and yet media will have you believe that using sunscreen is bad because sun is the natural way to get Vitamin D. Natural in this sense isn’t better. And ask any medical doctor and she/he will say that getting it through diet and supplements are the most efficient and efficacious way to re-tank your Vitamin D stores, not sun exposure.
Then there are the nay-sayers to sunscreen in general because of the chemicals within them. There are many types of sunscreens and it is up to consumers to make the right decision for themselves. Some are “chemically” based, some are “physical” sunscreens, and still others, which are often the best ones, are a combination of the two. I will not get into the controversies that rack the organic and “natural” world, and some may have some miniscule amount of merit in a very narrow, isolated setting. These issues will always be subject to constant debate. The real point is that the sunscreens on the market are truly safe, have been clinically thoroughly tested, which cannot be claimed by the organic and natural arena, and when used judiciously and consistently, we know that they effectively prevent skin cancer, wrinkling, and photoaging. Natural and organic when it comes to the skincare world are very much overrated and misleading. Let’s just say that poison ivy is also natural and organic, and if you have ever been stricken with it before, this natural state of the skin isn’t exactly a pleasant experience.
Let me be clear here by saying that sunscreens out on today’s market have been thoroughly tested and approved by the FDA and are such that they have been tested for safety and efficacy. In fact, several years ago, all sunscreens had to demonstrate clinical efficacy and/or undergo repeat testing and approval to claim efficacy, SPF strength, and water resistance. Because of these new regulations, the labeling had to be adjusted and changed to reflect these new guidelines. For instance, there is no such thing as a “waterproof” sunscreen in today’s American market anymore, and the maximum allowed claim for water resistance is 80 minutes.
Of course, it is up to one’s personal choice to choose which sunscreen to buy. Whether it is a physical sunscreen or a chemical sunscreen is not a topic most dermatologists are going to debate. Rather, the SPF number, the amount of sunscreen applied, the timing of application, the frequency that one reapplies, and simply the daily, regular use are the important factors for sun protection. I, as your dermatologist, am trying to keep your skin healthy. You come to see me for my opinion, and my opinion is for you to use your broad-spectrum, SPF 30-50 sunscreen, just like I do, every single day. End of story.
So those are my two cents about the SPF controversy. It is complex, nuanced, and vitally important. And yet my sunscreen messages to you are direct and simple. Broad-spectrum. SPF 30-50. Use it daily. Reapply it often. Forget the tan. Be an educated consumer. And your skin will be healthier for it.
Happy, Healthy Skin!
Read more about your skin and sun in our past blog posts:The SPF Controversy