Moisturizers Up Skin Cancer in Mice
4 Commonly Used Moisturizing Creams Promote Tumors in UV-Exposed Mice
Aug. 14, 2008 -- Four commonly used moisturizers promoted skin cancers in mouse
Mice are not men. But the unexpected finding suggests that these -- and
perhaps other products -- may not be as safe as they're thought to be.
The moisturizers tested in the study were Dermabase, Dermovan (a wholesale-only product discontinued in
2006), Eucerin Original Moisturizing Cream, and Vanicream.
In a mouse model of sun-related skin cancer, frequent
application of each product resulted in more skin tumors and faster tumor
growth, says study leader Allan H. Conney, PhD, director of the Susan Lehman
Cullman Laboratory for Cancer Research and professor in the school of pharmacy
at Rutgers University in Piscataway, N.J.
"This was unexpected. We really did not expect to see the
tumor-promoting activity of these creams," Conney tells WebMD.
In fact, Conney and colleagues were getting ready to use one of these
moisturizers -- Dermabase -- in human clinical trials of topical caffeine, which prevents skin
cancer in animal studies.
"We thought it would be prudent to test Dermabase by itself to see if it
had tumor-promoting activity," Conney says. "We did not think it would.
But lo and behold, to our surprise we got an increased rate of skin
This led to new tests of Dermabase and the three other moisturizers, which
the Conney team hoped to use in their human study. For these new animal
studies, the researchers used hairless mice irradiated with ultraviolet light
twice a week for 20 weeks. With no further irradiation, such mice eventually
develop skin cancer -- very much like humans overexposed to sunlight early in
Five days a week, for 17 weeks, the researchers rubbed moisturizer into the
animals' skin. The result:
- 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%.
"The multimillion-dollar question is, what about humans?" Conney
asks. "The answer is, we don't know. Our study raises a red flag and points
out the need for epidemiologists to take a look at people who use moisturizing
creams. And the companies that market these products should take a look at
animal models and see if their products promote tumors."
Testing Moisturizers for Safety
Dermatologist Keyvan Nouri, MD, director of dermatologic surgery at the
University of Miami Miller School of Medicine and author of the best-selling
book Skin Cancer, agrees that companies that make moisturizers should
test their products.
"This study could definitely be a warning to alert these companies to
consider testing moisturizing creams with some sort of assay," Nouri tells
WebMD. "These creams need to be tested first before they come to
Moisturizers are classified as cosmetics by the FDA, which does not require
that they undergo the same safety and efficacy tests required for drugs.