Thanks to TikTok and other social media platforms, the internet is rife with myths about sun exposure and skin cancer. From denials of the harmful effects of sun exposure to claims about carcinogens in sunblock, this kind of misinformation is often pervasive.

As we observe UV Safety Month this July, I’d like to debunk four common myths about sun exposure and skin cancer, offering scientific insights on how you can protect yourself from the harmful effects of ultraviolet (UV) radiation this summer. Learn more below.

Myth 1: There is no proof that sun exposure causes cancer.

The connection between sun exposure and skin cancer is well-documented through extensive research. Ultraviolet (UV) radiation from the sun creates oxidative stress and damages the DNA in skin cells, leading to mutations that can result in skin cancer. Numerous epidemiological studies have demonstrated higher rates of skin cancer in individuals with significant sun exposure.^1,2,3 Prolonged sun exposure can also harm the eyes, leading to cataracts and other ocular issues.^4,5

UV rays are classified into two main types: UVA rays and UVB rays. While both types contribute to the formation of skin cancer, UVB radiation is a greater contributor, as it causes sunburn and direct DNA damage. UVA rays, on the other hand, penetrate deeper into the skin, contributing to indirect DNA damage and skin aging. Sunburn is a clear sign of skin damage from UV radiation. Repeated sunburns, particularly in childhood, significantly increase the risk of developing skin cancer later in life. The inflammation and damage from sunburn contribute to cumulative DNA mutations that can trigger cancerous changes.⁶

Myth 2: People who wear sunscreen are always getting skin cancer.

There is no data to support this claim. In fact, studies have shown that regular use of sunscreen, including those containing carcinogens, reduces the risk of developing skin cancer, including melanoma, the most dangerous form of skin cancer. Sunscreen acts as a barrier that blocks or absorbs harmful UV radiation, preventing skin damage.^7,8

Myth 3: In the late 1970s, skin cancer increased because people started wearing sunscreen more often.

While the reported incidence of skin cancer has increased over the past few decades, this has been attributed in part to factors such as increased sun exposure, improved diagnostic techniques, and greater public awareness, resulting in more skin cancers being detected and reported.⁹

In recent decades, not only have Americans experienced higher exposure to carcinogens,^10,11 but the nutrient content of the U.S. food supply has decreased.¹² A diet lacking in essential nutrients and antioxidants such as polyphenols can weaken the skin’s ability to repair UV-induced damage.¹³

Myth 4: All non-mineral-based sunblocks are toxic.

While some chemical-based sunscreens contain ingredients that have raised safety concerns, not all chemical sunscreens are harmful. You can optimize the safety of your sunscreen by knowing which ingredients are safe and which ingredients have potential carcinogenic effects, indicated below:

• Potentially carcinogenic ingredients: Oxybenzone, Octinoxate, PABA (Para-aminobenzoic acid), Retinyl Palmitate.
• Safe ingredients: Zinc Oxide, Titanium Dioxide, Avobenzone, Mexoryl SX, Tinosorb S and M.^14,15

Mineral-based sunscreens that use zinc oxide or titanium dioxide are generally considered safe and effective. They work by reflecting UV radiation away from the skin and are often recommended for individuals with sensitive skin or concerns about chemical absorption. These sunscreens are less likely to cause skin irritation compared to their chemical counterparts. Titanium dioxide has long been proven safe for cosmetics, being non-irritating and suitable for sensitive skin. Additionally, zinc oxide not only protects the skin from UV radiation but also acts as an anti-irritant. ^16,17

Tips for buying sunscreen

By carefully selecting sunscreens based on ingredients, you can find both mineral and chemical-based options that are effective and free from potential carcinogens. To guard against both UVA and UVB rays, choose a sunblock with broad-spectrum protection and an SPF of 30 or higher. It’s also beneficial to choose products that suit your skin type, such as oil-free or hydrating formulas, and to select water-resistant formulas when swimming or sweating.

Be cautious with aerosol sunscreens, as their ingredients can be inhaled and pose potential health risks. For example, the aerosol sunscreen ingredient benzene can be absorbed through the skin or inhaled. Short-term exposure to high levels of benzene can cause headaches, dizziness, and in some cases can even be fatal. Choosing the right sunscreen can significantly reduce these risks while providing effective sun protection.

If you’re not sure where to start, the Environmental Working Group (EWG) provides annual sunscreen guides that rate the safety and efficacy of sunscreen products based on their ingredients.

In addition to using sunscreen, here are some other ways to keep your skin healthy:

1. Incorporate antioxidants and other supplements into your diet.

Be sure to consume a diet rich in nutrients and antioxidants by eating plenty of fruits and vegetables. Antioxidants play a critical role in combating oxidative stress, reducing DNA damage, and preventing malignant transformations of cells. Vitamins C, E, and A, along with zinc, selenium, beta carotene, omega-3 fatty acids, lycopene, and polyphenols, are recommended to help prevent skin cancer by mitigating the damaging effects of reactive oxygen species (ROS), which are believed to damage RNA, DNA, and proteins. Recent research supports the role of antioxidants in reducing skin cancer risk, and more and more dermatologists now advise increasing the intake of these nutrients and using topical products containing them.¹⁸

You may also want to consider taking supplements with the herb Polypodium, which has been shown to provide protection against the sun.

2.  Be strategic about activities and attire when outdoors.

You can protect yourself from damaging sun exposure by planning your activities and attire accordingly. If possible, schedule outdoor activities for early morning or late afternoon to avoid the highest intensity UV rays, which generally occur from 10:00 a.m.-4:00 p.m. You can also wear or use protective clothing and gear, such as long-sleeved shirts, wide-brimmed hats, UV-blocking sunglasses, and portable shade devices.

3. Consider applying castor oil to your skin to strengthen your skin’s natural defenses and protect it from UV-induced oxidative stress.

One of the human body’s natural defenses for skin is the hydrolipidic film. Located on the surface of the epidermis, the hydrolipidic film helps protect skin from UV rays, pollution, and dehydration. However, the hydrolipidic film can be weakened by sun exposure. Applying castor oil after sun exposure helps recreate this film because it contains oleic (omega-9) and palmitoleic (omega-7) acids, which are the compounds naturally present in the hydrolipidic film.

Additionally, the linoleic acid in castor oil can also facilitate the formation of the skin’s waterproof barrier, which may be weakened by sun exposure.

Castor oil also contains tocopherols (Vitamin E), powerful antioxidants which protect the skin from oxidative stress caused by UV rays. Notably, Vitamin E can transform hydrogen peroxide (H₂O₂) into water (H₂O), before it damages cells. Regular application of castor oil has a photoprotective effect and helps to limit the damage that UV rays can cause.

Comprehensive Sun Protection with Solidarity HealthShare

For all patients, I recommend a comprehensive strategy for healthy skin, including the use of safe sunscreens and other protective measures discussed above. For early detection and treatment of skin conditions and cancer, be sure to schedule dermatology appointments, which are eligible for sharing at Solidarity.  I encourage you be proactive and adopt these year-round sun protection habits to reduce the risk of skin cancer and other sun-related skin damage.

1. Armstrong BK, Kricker A. The epidemiology of UV induced skin cancer. J Photochem Photobiol B. 2001 Oct;63(1-3):8-18. doi: 10.1016/s1011-1344(01)00198-1. PMID: 11684447. ↩︎
2. Gilchrest BA, Eller MS, Geller AC, Yaar M. The pathogenesis of melanoma induced by ultraviolet radiation. N Engl J Med. 1999 Apr 29;340(17):1341-8. doi: 10.1056/NEJM199904293401707. PMID: 10219070. ↩︎
3. Godic A, Poljšak B, Adamic M, Dahmane R. The role of antioxidants in skin cancer prevention and treatment. Oxid Med Cell Longev. 2014;2014:860479. doi: 10.1155/2014/860479. Epub 2014 Mar 26. Erratum in: Oxid Med Cell Longev. 2020 Aug 27;2020:1969760. PMID: 24790705; PMCID: PMC3984781. ↩︎
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