I explain the harmful effects that UV radiation causes here, now let’s talk about how we can PREVENT these effects from occurring in our skin.
Total sun protection refers to thoroughly and adequately protecting your skin from the harmful effects of the sun. Total sun protection includes the use of sunscreen, sun-protective clothing, supplements, use of shade while outdoors, and avoidance when proper protection measures aren’t possible. I will teach you about each of these measures, starting with sunscreens.
Sunscreens are a KEY component of photoprotection and something that I talk about a lot during patient consultations. There is a vast sea of information (and misinformation!) on the internet, blogs, social media, magazines, TV ads, and more about sunscreen. It is no surprise that patients are coming to me now more confused than ever about this issue.
I am going to tell you what we DO know from high-quality scientific studies about sunscreen in terms of its effectiveness and safety.
Evidence that sunscreen is effective:
Sunscreen use leads to a reduction of the three most common types of skin cancer: squamous cell carcinoma, basal cell carcinoma, and melanoma.
Additionally, sunscreens can prevent pre-cancers called actinic keratoses. In particular, long-term use of sunscreen has been shown to reduce the risk of melanoma, which is one of the most deadly forms of skin cancers. Unfortunately, the incidence rate of melanoma continues to increase in the United States. This rate is projected to rise over the next 15 years IF we do not change our high-risk behavior and improve prevention efforts.
Sunscreen prevents photoaging.
The appearance of sun-induced skin aging is different than the appearance of natural aging of the skin that occurs over time. Natural aging is due to the loss of fat under the skin. With this type of aging, the skin will still be smooth and unblemished, but it will show changes of fine wrinkling and thin skin. Sun-damaged skin causes coarse wrinkles, uneven pigmentation (spots), and a leathery look to the skin. Under the microscope, sun-damaged skin also appears different than naturally aged skin.
Sun-damaged skin shows an abundance of degraded elastotic material called dermal elastosis. Studies have shown that people who use sunscreen have significantly less evidence of the sun-damaged appearance to the skin. Further, people who apply a sunscreen with an SPF of 15 or higher daily show 24% less skin aging than those who do not use a daily sunscreen!
Sunscreen prevents sunburn.
According to the CDC, over half of high school students reported getting a sunburn within the last year (>60% of girls and >50% of boys). The same study showed that 37% of US adults reported having been sunburned in the past year. These are frightening statistics and show that we are doing a poor job of protecting ourselves in the sun. One of the facts I often share with my patients is that just one single blistering sunburn can nearly double your risk of developing melanoma. And 5 or more blistering sunburns between the ages of 15 and 20 increases one’s melanoma risk by 80% and increases non-melanoma skin cancer risk by 68%. Like I say all the time, sunburns are NOT just a temporary problem. They have long-term, serious consequences. This is even more important for people who are taking medications (such as acne medications) that make them more susceptible to sunburns or who have skin conditions that will flare-up in the sunlight. A broad-spectrum sunscreen will effectively prevent sunburn when applied in the appropriate concentration to achieve the SPF on the label.
Are sunscreens safe?
Clearly, sunscreens are an effective agent against the sun’s harmful UV radiation. This has been demonstrated in numerous studies, and we have known this for many years. Because of this research, sunscreen has been deemed SAFE by the FDA and earned FDA approval for the prevention of sunburns, skin or lip damage, freckling, skin discoloration, skin aging, and skin cancer.
However, I still have patients saying, “I read sunscreen is bad for you, and now I’m hesitant about using it.”
Much of this resurgence in controversy and confusion surrounding sunscreen safety is coming from a recent study published in JAMA. This study demonstrated that certain chemical sunscreen ingredients are absorbed into the bloodstream. This sounds scary and now has people concerned about the safety of using sunscreens. But what does this really mean for us and should we change our habits?
First of all, this was a single, small pilot study of 24 participants. Although it showed evidence of sunscreen ingredients in the bloodstream, we do not have any evidence that this absorption leads to actual adverse effects on a person’s health. In fact, these sunscreen ingredients have been used for many decades without any reported internal side effects in humans.
Because of these recent concerns and findings regarding sunscreens, the FDA issued a proposed rule asking manufacturers to provide MORE DATA about the safety of several sunscreen ingredients. Specifically, more information is needed on the extent that skin absorbs sunscreen ingredients and whether absorbing these ingredients has any effects on the skin or body.
Currently, the FDA has classified sunscreen ingredients into one of three categories:
- Generally recognized as safe and effective (GRASE) for use in sunscreens: This includes zinc oxide and titanium dioxide (ingredients found in physical blocking sunscreens).
- Not GRASE for use in sunscreens: This includes PABA and trolamine salicylate which are not legally sold in the United States, and therefore irrelevant.
- Insufficient data for use in sunscreens: These include 12 chemical ingredients that can be found in sunscreens, of which 6 are commonly used in the US (ensulizole, octisalate, homosalate, octocrylene, octinoxate, oxybenzone, avobenzone).
The FDA also released the following statement:
“Given the recognized public health benefits of sunscreen use, Americans should continue to use sunscreen and other sun-protective measures as this important rulemaking effort moves forward.”
If you remain concerned about the absorption of these particular sunscreen ingredients mentioned in the JAMA study, you can select sunscreens known as physical blockers. This category of sunscreen does NOT contain chemical ingredients and does not absorb into the skin like chemical sunscreens. The difference between chemical and physical sunscreens and how to pick the right sunscreen for yourself is discussed here.
Remember what we know! We KNOW that UV radiation is a human carcinogen. We KNOW that UV radiation is absorbed by human skin. And we KNOW that absorption of this carcinogen leads to skin cancer and other adverse outcomes. We use sunscreens to prevent these known and studied harmful effects on humans. We must not disregard sunscreen in light of recent unsubstantiated findings.
Unfortunately, it can be easy to get led astray by clickbait headlines in the media. I bring you this information and commentary to help you understand the claims in the media so that you can make the most informed decision for your own health.
Now that you know sunscreen is essential and effective, you MUST understand how to select the right sunscreen for yourself and understand how to use it correctly. Chances are…you are NOT getting the protection you think you are!
In this next post, I will tell you exactly how to STOP misusing your sunscreen and how to START getting real results from your SPF.
References:
- American Academy of Dermatology. “American Academy of Dermatology comments on recent study on absorption of sunscreen ingredients.”6 May, 2019. https://www.aad.org/media/news-releases/study-sunscreen-ingredients.
- Boyd AS, Naylor M, Cameron GS, et al. The effects of chronic sunscreen use on the histologic changes of dermatoheliosis. J Am Acad Dermatol. 1995;33:941-946.
- Center for Disease Control and Prevention. “Sunburns.” https://www.cdc.gov/cancer/skin/statistics/behavior/sunburns.htm. 2018.
- Green A, Williams G, Neale R, et al. Daily sunscreen application and betacarotene supplementation in prevention of basal-cell and squamous-cell carcinomas of the skin: a randomised controlled trial. Lancet. 1999; 354:723-729.
- Green AC, Williams GM, Logan V, et al.: Reduced melanoma after regular sunscreen use: randomized control trial follow-up. J Clin Oncol. 29:257-263 2011.
- Gurish MF, Roberts LK, Krueger GG, et al. The effect of various sunscreen agents on skin damage and the induction of tumor susceptibility in mice subjected to ultraviolet irradiation. J Invest Dermatol. 1975;65:543-546.
- Guy GP, Thomas CC, Thompson T, Watson M, Massetti GM, Richardson LC. Vital signs: Melanoma incidence and mortality trends and projections—United States, 1982–2030. MMWR Morb Mortal Wkly Rep. 2015;64(21):591-596.
- Hughes MCB, Williams GM, Baker P, Green AC. Sunscreen and prevention of skin aging: a randomized trial. Ann Intern Med 2013; 158(11):781-790.
- Iannacone MR, Hughes MC, Green AC. Effects of sunscreen on skin cancer and photoaging. Photodermatol Photoimmunol Photomed. 2014 Apr-Jun;30(2-3):55-61.
- Murali K. Matta, PhD1; Robbert Zusterzeel, MD, PhD, MPH1; Nageswara R. Pilli, PhD1; et al. Effect of Sunscreen Application Under Maximal Use Conditions on Plasma Concentration of Sunscreen Active Ingredients. A Randomized Clinical Trial. JAMA. 2019;321(21):2082-2091.
- Naylor MF, Farmer KC. The case for sunscreens: a review of their use in preventing actinic damage and neoplasia. Arch Dermatol. 1997; 133:1146-1154.
- U.S. Food and Drug Administration. “FDA advances new proposed regulation to make sure that sunscreens are safe and effective.” https://www.fda.gov/news-events/press-announcements/fda-advances-new-proposed-regulation-make-sure-sunscreens-are-safe-and-effective. 2019.
- U.S. Food and Drug Administration. “Sunscreen: How to help protect your skin from the sun.” Last updated 2/21/2019.