Sunscreen Facts Worth Knowing

The watchdog Environmental Working Group and skin cancer experts demystify UVB and UVA rays, broad-spectrum products, and super-high SPF values while denouncing sunscreen pills.


Illustration by Raisa Yavneh

Summer is fading, but the Bay Area usually gets a spate of warm weather in early fall. Fog dissipates. Temperatures can soar. Don’t put away your sunscreen. Actually, dermatologists would tell you to make your sunscreen a yearlong habit, along with hats and noonday shade. Skin cancer experts will also tell you to use sunscreen that truly protects you, and to use it correctly.

While there’s some disagreement about what makes an optimal sunscreen, there are many shared views, including the importance of knowing the basics of sunscreen, so you can use it wisely.

“The most important thing hands down is that the ultraviolet radiation in the sunlight is a powerful carcinogen, and there’s no doubt that ultraviolet radiation leads to not only skin cancer, but freckling, age spots, and loss of tissue elasticity,” said Sarah Aaron, a dermatologist and skin cancer expert at UCSF Medical Center.

“My primary goal as a dermatologist is to help my patients find a sunscreen that works for their individual skin and that they find palatable to use frequently and correctly,” she said.

This summer, the Environmental Working Group, a national nonprofit consumer watchdog group, released its annual 2018 sunscreen report, which reviewed 1,000 products, including lip balms and moisturizers, that claim sun protection. It has tracked sunscreen safety, effectiveness, and marketing since 2007, positioning its work as a better guide for consumers than the Federal Drug Administration, which regulates sunscreens. To look at the EWG’s recommended list of sunscreens go to:

About one-third of sunscreen products tested this year received a favorable rating, which looked at two criteria: ultraviolet or UV protection and health safety. Sunscreen quality has improved, but more work needs to be done, the group said.

The main takeaways of the EWG’s 2018 sunscreen report included:

• The SPF or sunscreen protective factor rating system is misleading because it’s based only on ultraviolet B rays or UVB rays, not ultraviolet A rays or UVA rays, and both can cause cancer. Look for “broad spectrum” protection that also filters UVA rays. SPF ratings of 50-plus or greater don’t translate to proportionately more sun protection. Ratings up to SPF 50 are meaningful.

• “Consumers are being pushed to super-high SPF products that may provide a false sense of security and lead people to spend more time in the sun,” senior scientist David Andrews said. 

• Advised against using products with oxybenzone, a hormone disruptor that can harm health, and retinyl palmitate, a form of vitamin A that can harm skin. Oxybenzone in sunscreen was banned in Hawaii in July because it kills coral reefs. Hawaii is the first state to take this step.

• Favored mineral-based sunscreens, particularly those using zinc oxide and titanium dioxide, as effective in blocking both UVA and UVB rays.

• The EWG is lobbying the FDA to improve and speed up testing of UVA protection, including ingredients used in Europe. The REG advocated capping SPF ratings at 50, a trend abroad.

“People pick sunscreen based on the SPF value and falsely assume that preventing sunburn means they have protected their skin from all UV damage,” said a EWG statement. “Many sunscreens don’t provide adequate protection from UVA rays.”

Hats, sunglasses, clothing, and, importantly, avoiding direct sun during the brightest time of the day are essential to sun protection, experts agreed.

“My overall message is to limit sun exposure particularly between 10 and 2 when the sun is at its peak,” said dermatologist Aaron.

She also reminded tanning fans that tanning beds emit UVA and UVB rays and aren’t safer than natural sun. Aaron said many products do a pretty good job of protecting against UVB and UVA rays, as long as they’re used correctly and labeled “full spectrum.” She said she favored sunscreens using the ingredient helioplex, which protects against both types of rays.

She agreed that SPF ratings are confusing and that many people don’t understand they apply to only one kind of harmful ray — UVB. But testing UVA exposure isn’t accurate enough yet for a reliable rating system, she said. UVB exposure causes sunburn, which can be measured. UVA exposure causes cellular damage, “and these aren’t simple tests to run,” Aaron said.

Aaron said she understood that some people preferred using products that are the most natural, or least chemical based, such as mineral sunscreens. But these aren’t for everyone, she said.

The most important thing is liberally using a broad spectrum sunscreen that works for your skin and lifestyle, in addition to other sun protection tactics, Aaron said.

So-called recent “sunscreen pills” marketed as an oral option for sun protection have skin experts worried, and the FDA told four companies making them that they’re illegally marketing them and making  unproven drug claims about their effectiveness.

“There are no effective sunscreen pills,” Aaron said. “I’d be very worried about someone taking a supplement that suggests they don’t need a topical sunscreen.”