Is There a Link Between Sunscreen and Endometriosis?

Warm spring sunshine lifts our spirits and makes us feel good all over. But it’s also a reminder to break out the sunscreen to protect our skin from harmful UV rays. But could sunscreen pose a risk in itself? Researchers are investigating a possible link between a sunscreen ingredient called benzophenone (BP) and endometriosis.

In the first study of its kind, researchers analyzed BP levels in 625 women who had undergone surgery for endometriosis. They discovered that high levels of a specific BP, called 2,4OH-BP, were associated with a higher risk of an endometriosis diagnosis.

The women in the study lived in California and tended to have higher levels of BPs during the summer, leading researchers to suspect a link with sunscreens.

What do BPs do?
BP-type ingredients are used in sunscreens and personal care products because they effectively block harmful ultraviolet rays. Unfortunately, small amounts of BPs can be absorbed through the skin and into the blood, where they mimic the effects of estrogen.

What is endometriosis?
Endometriosis is a painful condition in which uterine tissue grows outside of the uterus. It affects one in 10 women of reproductive age.

Endometriosis needs estrogen to develop, leading researchers to speculate that there may be a link between BPs in sunscreen and endometriosis. The study is published in Environmental Science & Technology.

Confused about sunscreens?
If you’re unsure about which sunscreen to use, or want to learn more about the ingredients in specific sunscreen products, check out the Environmental Working Group’s "Sunscreen Report" for 2011. Their 2012 report is coming soon!

Summer skin care tips
Read "Your Best Summer Skin" in the May issue of alive to discover how to keep your skin beautiful and healthy this summer.