It should be simple enough: When out in the sun, wear sunscreen. But knowing what’s in your sunscreen is as important as putting it on. There are concerns about some ingredients, both active and inactive, that you may find in your sunscreen.
There’s no doubt you should be lotioning up: Almost 9,500 people in the United States are diagnosed with skin cancer every day, according to the American Academy of Dermatology. And it’s estimated that roughly 161,790 new cases of melanoma — the most dangerous form of skin cancer — will be diagnosed in 2017. Where the doubt lies now is in what’s in the sunscreen you choose. Here are 3 ingredients that you should avoid, plus 3 must-have ingredients that make a good sunscreen.
3 Ingredients to Avoid
Read the label and look for oxybenzone, octinoxate, avobenzone and ecamsule, common ingredients in sunscreens with unknown toxicity concerns. An FDA study just proved that they and are absorbed into the the bloodstream through your skin in high enough levels that the FDA is setting new requirements for manufacturers to study them further.
Other studies indicate that these chemicals have been linked to disruption of sperm function in men and estrogen in women. Oxybenzone (UV filter) and octocrylene (an emulsifier) are two of those ingredients.
The full risks of these chemicals are unknown and for now the FDA and most dermatologists encourage people to continue to use sunscreen (apply 25-30 minutes before going out into the sun and repeat following the instructions). Sunburn and skin cancer appear to be the greater risk.
To completely avoid hormone disruptors, you’d have to use physical (inorganic) sunscreens, such as titanium dioxide or zinc dioxide, which sit on your skin and literally bounce away the sun’s rays. (Remember the white stuff on the lifeguard’s nose?) You don’t have to apply these in advance because they don’t need to be absorbed to work.
Another ingredient in question is retinyl palmitate, a form of Vitamin A. Retinoids are often used to reverse sun damage and even prevent skin cancer, but when they are added to sunscreens, they may cause more harm than good. The question is whether retinyl palmitate breaks down in the sun and becomes carcinogenic.
“I like it for anti-aging; I don’t like it in the sun,” says Debra Jaliman, MD, associate professor of dermatology at Mount Sinai School of Medicine in New York. “It thins your skin, so it can make the sun penetrate more and there’s research that it’s not so good in sunlight.”
The good news is that the number of products containing retinyl palmitate has dropped dramatically. In 2010, about 40% of the sunscreen products reviewed by the Environmental Working Group (EWG) has the additive. But in EWG’s 2017 Guide to Sunscreens, it dropped to just 14%.
More recently there have been concerns about spray sunscreens causing harm because they can be inhaled into the lungs. Also, there is some evidence that the sprays do not provide an even coating on the skin the way a lotion does. The FDA is considering further research to evaluate the safety of these products.
But for many people, the convenience of a spray over a lotion means they’ll actually use the sunscreen — and that’s the most important message of all.
3 Must-Have Ingredients
Broad Spectrum Protection
Most dermatologists agree that sunscreens should contain protection from both UVA and UVB rays. “UVB leads to burning of the skin, but UVA penetrates even deeper into the skin and is linked to aging and skin cancer,” says Roopal Kundu, MD, associate professor in dermatology and medical education at the Feinberg School of Medicine at Northwestern University in Chicago.
Not long ago, sunscreens only protected against UVB so people would tan, not burn. This led to a false sense of security, says Diane S. Berson, MD, associate clinical professor of dermatology at Weill Medical College of Cornell University. “In reality they were getting more UVA which contributes to the development of skin cancer.”
Sun Protection Factor (SPF) of at Least 30
Although the FDA suggests a minimum of 15 SPF, the American Academy of Dermatology recommends no less than 30 SPF, which blocks 97% of the sun’s rays — that’s 30 times the protection than if you’d gone out with none at all. While higher SPF might add a bit more, nothing is 100%, warns Dr. Kundu.
Also, sunscreen should be reapplied every two hours to be effective.
You’re not going to see label claims that were once prominent, like “waterproof” or “sweatproof.” The FDA banned the use of those terms under regulations issued in 2011. Instead, manufacturers use the term water resistant to describe a sunscreen’s ability to maintain its effectiveness.
If you’re going to swim or be active outside, then choose a sunscreen that’s water resistant and plan to reapply every 40-80 minutes.
Compliance is Key
“If a person is irritated by what they’re using or it feels greasy or heavy, then they’re not going to use it,” says Dr. Berson. “I want it to be efficacious and also cosmetically acceptable so they use it.”
According to Steven Q. Wang, MD, director of dermatologic surgery and dermatology at Memorial Sloan Kettering Cancer Center in Basking Ridge, NJ, people should avoid the sun and wear hats and protective clothing — sunscreen is the last line of defense.
First published May 22, 2015, and updated annually.