Sunscreen under siege 

By Drs. Leora Aizman & Manisha Loss, Johns Hopkins Medicine 

In the fast-paced era of TikTok, misinformation spreads like wildfire, and sunscreen is this summer’s latest target. Amid viral dances and creative recipes, influencers have been promoting unfounded claims about SPF products. Gen Z and Gen Alpha, digital natives who often turn to social media for health advice, are particularly vulnerable to these misconceptions. Clinicians face a critical challenge: to cut through the noise of viral content and ensure younger generations understand the importance of proper sun protection in long-term skin health. 

Here are a few things to discuss with patients:  

Does sunscreen cause cancer? 

The misconception that sunscreen causes cancer gained traction following the discovery of benzene contamination in some sunscreen products in 2021. Benzene, a known carcinogen linked to hematologic malignancies, was found in concentrations exceeding the Food and Drug Administration’s (FDA) maximum allowed concentration, leading to product recalls. Benzene isn’t an intentional sunscreen ingredient but rather a manufacturing contaminant primarily associated with aerosol sprays. Similar recalls have occurred in other aerosol products like deodorants, dry shampoos, and insect repellents. 

To mitigate potential benzene exposure, consumers can opt for non-spray sunscreens such as lotions and creams. The FDA continues to encourage sun safety and the use of broad-spectrum sunscreens with SPF values of at least 15. Remind patients that the risk of skin cancer from UV radiation far outweighs any potential risk from sunscreen use! 

Is sunscreen absorbed into the bloodstream?  

Organic UV filters found in chemical sunscreens (avobenzone, oxybenzone, octocrylene, homosalate, octisalate, and octinoxate) have been detected in the bloodstream after routine use of sunscreen. However, their presence in the blood doesn’t necessarily mean they’re harmful. While further research is needed, current evidence doesn’t show adverse health effects from sunscreen use in humans. 

In contrast, inorganic UV filters like zinc oxide and titanium dioxide, which are used in mineral sunscreens, don’t appear to be absorbed systemically. These ingredients have been deemed “GRASE” (generally recognized as safe and effective) by the FDA. 

Does sunscreen prevent you from getting enough vitamin D? 

Vitamin D is a hormone produced in the skin upon exposure to ultraviolet B (UVB) rays. While sunscreen aims to block UV light exposure, even perfect application of SPF 50 allows 2-3% of sun rays to pass through. Studies have shown that sunscreen use has minimal, if any, impact on vitamin D levels, likely due to underapplication. For those concerned about vitamin D, consider vitamin D-rich foods or supplements. 

Does a base tan prevent sunburn and skin cancer?  

A base tan offers minimal protection, equivalent to only SPF 3 or 4, allowing over 25% of UVB rays to penetrate the skin and cause damage. There’s no such thing as a safe tan. Tanning is a sign of skin damage, with the skin darkening due to an increase and redistribution of melanin as a defense mechanism against further DNA injury. 

Does drinking water prevent sunburn?   

While staying well-hydrated is essential for overall health, drinking water doesn’t prevent sunburn. The skin requires a defense mechanism like a shield (melanin pigment, mineral sunscreen, sun protective clothing) or an absorber (chemical sunscreen, which absorbs UV rays, converts them into heat, and releases them from the body) to stay protected from UV rays. Drinking water doesn’t contribute to either of these protective measures. 

Remember to tell patients about:  

1. Proper sunscreen use. 

Recommend broad-spectrum sunscreens with SPF 30+, reapplied every two hours or more frequently when swimming or sweating. 

2. Non-aerosol sunscreens.

For patients concerned about potential contaminants, suggest using lotion or cream sunscreens and mineral-based products. 

3. Turn to trusted sources of health information instead of social media. 

 Advise patients to seek guidance from reputable health organizations, like the American Academy of Dermatology, and consult board-certified dermatologists, who are experts in skin, hair, and nail health. 

This piece expresses the views solely of the author. It does not necessarily represent the views of any organization, including Johns Hopkins Medicine.