Michael Girardi understood the importance of sunscreen from an early age. When he was a kid, his uncle died from melanoma.
"My cousins were left without their father," said Girardi, vice chair for faculty development and scientific innovation and the Evans Professor of Dermatology at Yale School of Medicine. "That had a profound influence on my interest [in medicine]."
As a dermatologist, Girardi has worked with many patients who have had extensive, and potentially deadly, melanoma and other types of skin cancer. Most skin cancers are caused by excessive exposure to ultraviolet (UV) rays. Protection from UV rays is important all year but especially during the summer months when people often spend more time in the sun.
Using sunscreen is one of the best ways to stay safe in the sun, and there are a lot of different kinds. And now, one more option will soon be available to Americans. This month, the U.S. Food and Drug Administration (FDA) approved the first new sunscreen ingredient in more than 25 years. But the ingredient, bemotrizinol, isn't new; it's been used for decades in Europe and Asia.
In an interview, Girardi discusses the best sunscreen options for consumers, whether a sunscreens SPF (Skin Protection Factor) matters, and why the newly approved sunscreen agent offers a valuable new option.
The interview has been edited for length and clarity.
Why is sunscreen so important?
Michael Girardi: Most people want to live active lives and spend time outside, especially during the summer months when the sun is that much more intense in our hemisphere. That's going to mean a lot of exposure to direct sunlight. Ultimately, there's going to be exposed areas of skin that benefit from sunscreen applications to really minimize someone's risk of burning, which is the primary association with melanoma. The risk of chronic exposure is squamous cell carcinoma.
What are the main types of sunscreens?
Girardi: The major categories in sunscreens are usually referred to as organic (chemical) and non-organic (mineral). Organic refers to molecules that have carbon ring structures that absorb ultraviolet, or UV, light. Inorganic refers to either titanium dioxide or zinc oxide, which are generally blockers and reflectors of UV light.
The FDA just approved the first new sunscreen ingredient in more than 25 years. Tell us more about that.
Girardi: Prior to this recent approval, there were only 16 agents, or active ingredients, that the U.S. FDA allowed to be used in sunscreen formulations. They really pump the brakes on introducing new agents because a lot of the agents that were already approved had some serious safety concerns. Some of them would bind hormone receptors like estrogen receptors, and a lot of them would achieve blood levels for which there's supposed to be further safety testing. When sunscreens are used, they're intended to be used with high amounts being applied to the skin repeatedly; that's the recommendation to achieve protection. However, that ultimately has the potential to result in some of these chemicals getting through the skin into the bloodstream. So, out of major precaution and safety concerns, this has slowed down the development of newer agents.
I'm pretty excited about this agent, bemotrizinol, because it's gone through the highest level of testing of any agent that's been approved. It's really a game changer in that it has the benefits of being an organic compound inasmuch as it's virtually invisible, as opposed to the inorganic mineral ones, and doesn't penetrate into the skin similarly to the inorganic mineral ones. Like a mineral compound, it blocks both UVA and UVB; most of the organic ingredients currently available block one or the other. This has to do with the fact that it's a large size. It is not easily absorbed into the skin, and provides dual UV absorption across both UVA and UVB ranges. This is a very different organic agent in terms of how it behaves, in a positive way, but also in terms of the safety that we've seen.
When it comes to sunscreen, what ingredients are best? What should we look for on the label?
Girardi: There's not a simple answer to that question. My general recommendation is to lean heavily into the inorganic, or mineral-based, sunscreens and try to minimize the chemical exposures. That means looking for ingredients like zinc oxide or titanium dioxide. I generally recommend mineral sunscreens because there's very little evidence of any of those ingredients getting absorbed through the skin.
How much does SPF matter?
Girardi: A product's SPF needs to be at a level of 30 to even be called a sunscreen nowadays [SPF is a measure of how much UV radiation is required to produce sunburn on protected skin relative to the amount of solar energy required to produce sunburn on unprotected skin, according to the FDA]. As the SPF value increases, sunburn protection increases.] We used to say minimum of 30 is the recommendation, but now it's not a sunscreen unless it's at least 30. It doesn't get that much better as you dial up that number. It's not like SPF 60 is twice as good as SPF 30. Unless you have ultra sensitivity to the sun or certain medical conditions, the sweet spot is 30, maybe up to 50 for a little extra benefit.
A lot of us work on our tan over the summer. Is there a safe way to tan?
Girardi: Artificial tanning has gotten a lot better. If people want to achieve a certain coloration, these are dyes that get sprayed on or foams that get rubbed on and can give you a coloration that might be desirable. In general, slow tanning in the sun is going to expose your skin to the damaging effects of of sunlight.
What other ways can we protect our skin this summer?
Girardi: We want a real good balance of enjoying life, getting out there, exercising, and socializing. We want to protect ourselves while we're out there. A broad brimmed hat is critical for protection; we want to have about two inches of extension around a brim of a hat that wraps all the way around. That's much better than a baseball cap or even a bucket hat. There's also sun protective clothing now that's light and cool and still allows us to get outside in the sun and minimize exposure to UV but also minimize how much sunscreen we may need. There are also daily moisturizers and makeups that can have SPF within them that can really simplify potential applications, for example, to the face. On top of that, we can look at the time of day and look at what the UV index is and make some common sense judgments as to when we're going to schedule our outdoor activities.
