I was taping a segment for the Oprah Winfrey Show in Chicago which saw me recommending Eucerin, shea butter or cocoa butter for dry heels (and it just occurred to me that lanolin is a great option, too) and as I was setting up the table one of the camera men said, “Oh, Eurcerin, isn’t that the moisturizer that causes cancer?” First, did this man really think I would recommend something that caused cancer? And second, how did he come to such a conclusion? One reason and one reason only: a stray news story that made the rounds on the Internet. This study that reported there were four moisturizers that caused tumors in mice.
I just love headlines like that. What better way to get readers to pay attention then to scare the hell out of them (or, alternatively, offer them an unrealistic miracle). This headline read “Four commonly used moisturizers promoted skin cancers in mouse studies.”
Here are the details of the article: The study appeared in the Aug. 14 issue of the Journal of Investigative Dermatology. The moisturizers tested in the study were Dermabase, Dermovan (a wholesale-only product discontinued in 2006), Eucerin Original Moisturizing Cream, and Vanicream. The test subjects were mice. Moisturizers were applied to the mice and they were exposed (unprotected) to UV light. The results showed that frequent application of each moisturizer resulted in more skin tumors and faster tumor growth. Of course, the researches said that what happened was completely unexpected because the moisturizers didn’t contain any ingredients that would ever be considered as tumor-promoting.
The researchers used hairless mice irradiated with ultraviolet light twice a week for 20 weeks. But even with no further irradiation (exposure to sun light), such mice eventually develop skin cancer anyway.
Five days a week, for 17 weeks, the researchers rubbed moisturizer into the animals’ skin. The results:
- Dermabase increased the total number of tumors by 69%.
- Dermovan increased the total number of tumors by 95%.
- Eucerin increased the total number of tumors by 24%.
- Vanicream increased the total number of tumors by 58%.
This study poses more questions than answers or conclusions. UV radiation damaged the skin of the mice before the moisturizing creams were applied which could account for the tumor-promoting effect and the variation a statistical random outcome (as can happen with cancer-prone mice).
What is it about these moisturizers that might promote cancer? Nothing. That’s the point: all of the products tested use different ingredients, so exactly what, if anything, might be linked to cancer isn’t known. If anything is absolutely certain, it is clear that it is impossible to compare mouse skin genetically altered to get cancer to human skin. As one biochemist explained to me, did the researchers try the creams on mice that weren’t genetically altered to get cancer? Did the researchers use control groups exposed just to the moisturizers without prior UV exposure, or to UV light without subsequent moisturizers? This study is hardly worth headlines and doesn’t speak to the formulations of these products in any way. By the way, the cameraman for Oprah no longer believes Eucerin is a moisturizer to avoid!
