Healthy Glow or Harmful Glare? Myths and Facts about Sun and Skin Cancer

Summer means fun in the sun. Before heading out to the lake, the beach or your favorite outdoor activity, make sure you’re being sun smart. Skin cancer is the most common cancer in the U.S. In fact, one in five Americans will develop skin cancer in their lifetime. Although it can affect anyone regardless of skin tone, those with fairer skin (quick to burn, tan poorly) are much more susceptible to skin cancers related to sun exposure.

Some common myths about tanning can lead to long-term damage that for the most part cannot be reversed. Let’s clarify some myths to help protect you and your family this summer.

Can A Base Tan Protect You From Skin Cancer?

Myth: Getting a base tan protects you from skin cancer.

Fact: The idea of getting a base tan – either in the sun or from a tanning bed – to protect yourself from a skin-damaging sunburn is mostly fallacy.

Every time you expose yourself to ultraviolet (UV) radiation, your skin experiences direct DNA damage and varying amounts of oxidative stress. These signal your pigment-producing skin cells, melanocytes, to release and produce melanin to protect the skin.

Moderate amounts of UV radiation may be tolerated by certain individuals who tan easily and burn rarely, but the amount of oxidative stress and DNA damage experienced when inducing a tan outweighs the protective benefits of a “base tan” for many people. Unless you are being dropped in the middle of a desert island, naked and afraid, without the typical sun protective resources available to us today (shade, sun protective clothing, and topical sunscreens), it is hard to argue that any tan, especially one obtained from a tanning bed (more on “why” in the next myth), is “protective” against skin cancer.

At best, a moderate amount of natural sun exposure (from the sun) in individuals who tend to tan easily and burn rarely may induce a tan that could be helpful in a scenario when no access to sun protective measures is available. But, any amount of sun exposure leading to a burn or prominent tan (evidenced by conspicuous tan-lines) is likely doing more harm than good. In fair-skinned individuals who tan poorly, not at all, or only after experiencing a sunburn, a base tan is never a feasible way to protect yourself from the harmful effects of UV radiation.

Are Tanning Beds Safer Than the Sun?

Myth: Tanning beds are safer than the real sun.

Facts: More than a million people go to tanning salons on an average day in the U.S.¹ Just because they’re popular doesn’t mean tanning beds are the less dangerous option.

The lights used in tanning salons emit primarily UVA radiation, a wavelength of ultraviolet light that is ineffective at producing vitamin D and is very effective at breaking down collagen and elastin fibers, which leads to premature aging. Furthermore, some tanning beds emit 10-15 times greater the UVA radiation than would be received when exposed to natural light emitted by the sun.²

UVA lamps in sunbeds are favored by tanning parlors in part because they lead to an immediate tanning effect but not a lasting one. UVB radiation, in contrast, provides the necessary energy to produce vitamin D, and leads to a longer lasting and more protective tan. However, it is 1,000 times more effective at inducing sunburns and has a much more direct effect on damaging DNA.

Skin types that tan easily (darken with minimal amounts of sun exposure) may derive health benefits from ultraviolet light exposure in the form of vitamin D synthesis. However, those seeking a “base tan” are generally those that burn more easily, and for them the risks far outweigh the benefits; and the light emitted by tanning beds is largely ineffective at producing vitamin D.

Tanning Beds and Skin Cancer

Although there is some debate regarding the attributable effect of tanning bed use on development of skin cancers³, most subscribe to statistics that support a significant correlation between tanning bed use and an increased risk of developing skin cancer:

• Squamous cell carcinoma risk goes up by 58%⁴
• Basal cell carcinoma risk goes up by 24%⁵
• Melanoma risk goes up by 15-27%⁶

Instead of calling it a tanning machine, a more accurate description would be an aging machine. If the potential risk of skin cancer doesn’t concern you, keep in mind that the UVA rays delivered by indoor tanning can dramatically speed up how quickly your skin ages.⁷

Excluding your inherent genetics which are largely unmodifiable, ultraviolet rays and specifically UVA is the main modifiable factor that leads to skin aging. This means that what you pay in exchange for the short-term darkening in the pigment of your skin is damage to your collagen and elastin fibers and the pigment producing melanocytes, which can largely not be undone. This leads to premature wrinkles and dark spots and a loss of the elasticity, firmness, and even skin tone we associate with a youthful, healthy appearance.

Is a High SPF Enough for Sun Protection?

Myth: A high SPF is all you need for sunscreen.

Facts: An SPF of 30 or greater is a great start for a sunscreen. Sunscreens rated as SPF 30 or higher block 97% of the UVB emitted by the sun, which is adequate if used properly. However, SPF tells you nothing about the ability of the product to protect from UVA rays.

How to Protect Against Both UVA and UVB Rays

Products labeled “broad-spectrum” are intended to protect against UVB and UVA rays, but to know exactly how much protection you need to look for the “PA” (protection against UVA) scale. Products labeled PA+++ (3 “pluses”) provide the most protection.

Not all sunscreens are the same. Read the ingredient list on the label to determine the type of sunscreen – chemical and physical – before you buy it.

Physical Sunscreens vs. Chemical Sunscreens

Physical sunscreens are like a shield that blocks the sun’s rays and can leave a white layer on your skin though some are tinted. They provide both UVB and UVA protection. Look for these active ingredients:

• Zinc oxide
• Titanium dioxide

Chemical sunscreens absorb the sun’s rays like a sponge and don’t leave a white layer on your skin. Chemical sunscreens have these ingredients:

• Avobenzone
• Octisalate
• Octocrylene
• Homosalate
• Octinoxate
• Oxybenzone

Each type has its own pros and cons. Physical sunscreens may be better for people with sensitive skin and provide broad spectrum protection, but may be more inconsistent in their effectiveness, possibly because they are more difficult to apply.

Chemical sunscreens may be easier to apply and result in more consistent protection, but are associated with a higher rate of skin reactions and absorption into the bloodstream.

Chemical Sunscreen Ingredients

• Aminobenzoates, trolamine salicylate, and benzophenones are found in some sunscreens and should be avoided.
• Octinoxate and oxybenzone can be damaging to coral reefs, and oxybenzone is absorbed through the skin in high amounts8 (along with some other sunscreen ingredients,9 so it may be prudent to avoid these as well.
• Avobenzone is the only US approved chemical blocker that offers UVA protection.

Importance of Application (and Reapplication!)

The most important aspect that determines effectiveness of a sunscreen is appropriate application, which means adequate amounts and frequency of reapplication. If exposed to the sun for an extended period of time or engaged in water sports, sunscreens should be reapplied every 1-2 hours. I can’t tell you how many times patients claim “sunscreens don’t work for me,” but then admit during an entire day in the sun they never reapply.

Heat Can Decrease Effectiveness of Sunscreen

Also, be sure to also check for the expiration date and toss out old sunscreens. Leaving sunscreens in the sun or in your hot car can decrease their effectiveness, so be sure to store them in a cool place out of the sun.

References

• 1 Whitmore SE, Morison, WL, Potten CS, Chadwick C. Tanning salon exposure and molecular alterations. J Am Acad Dermatol 2001;44:775-80.
• 2 Calzavara-Pinton PG, Arisi M, Wolf P. Sunbeds and carcinogenesis: the need for new regulations and restrictions in Europe from the Euromelanoma perspective. J Eur Acad Dermatol Venereol 2019 Mar; Suppl 2; 104-109.
• 3 Reichrath J, Lindqvist PG, Gruijl FR, Pilz S, Kimball SM, Grant WB, Holick MF. A Critical Appraisal of the Recent Reports on Sunbeds from the European Commission's Scientific Committee on Health, Environmental and Emerging Risks and from the World Health Organization. Anticancer Res 2018 Feb;38(2):1111-1120.
• 4,5 American Academy of Dermatology. Indoor tanning fact sheet. Last accessed June 23, 2022.
• 6 Dessinioti C, Stratigos AJ. An Epidemiological Update on Indoor Tanning and the Risk of Skin Cancers. Curr Oncol 2022 Nov 17;29(11):8886-8903.
• 7 American Academy of Dermatology. Indoor tanning fact sheet. Last accessed June 23, 2022.
• 8 Akintilo L, Gendler E. The State of Sunscreens in the US: Caveat Emptor. J Drugs Dermatol 2020 Aug 1;19(8):799-801.
• 9 Matta MK, Zusterezeel R, Pilli NR, Patel V, Volpe DA, Florian J, Oh L, Bashaw E, Zineh I, Sanabria C, Kemp S, Godfrey A, Adah S, Coelho S, Wang J, Furlong L, Ganley C, Michele T, Strauss DG. JAMA 2019 Jun 4;321(21):2082-2091.