Posted on behalf of Katrina Charles, BA Media Fellow
Researchers have accidentally discovered that moisturisers can increase the rate of skin cancer in mice. While this is a perfect candidate for over hyping and fear mongering, it has received really balanced coverage in most cases. Instead, it has been rightly pointed out that hairless mice have different skin to humans (CBS, ABC, LA Times, Calgary Herald).
According to the paper, published online in Nature’s sister title the Journal of Investigative Dermatology, the hairless mice were exposed to UVB twice a week for 20 weeks, then had moisturiser applied 5 times a week for 17 weeks. The study started out as a control, using a popular US moisturiser, for testing if caffeine could prevent skin cancer.
“We wanted a safe cream that we could put the caffeine into,” says Dr Allan Conney of Rutgers University in New Jersey, one of the authors of the study (Reuters).
But what they found was that the moisturiser significantly increased the rate of both the formation and growth of a tumours in the mice, and this result was repeated with another three popular moisturisers.
Conney told the Calgary Herald, “I don’t think that people should be scared because this is a mouse study and we don’t know whether or not it applies to humans.”
As the Guardian points out, mice have a thin skin and live in the dark, “unlike humans whose bodies were designed for exposure to the sun”.
According to CBS, this has prompted a call from dermatologist Keyvan Nouri, MD, director of dermatologic surgery at the University of Miami Miller School of Medicine, for companies that make moisturisers to test their products.
“This study could definitely be a warning to alert these companies to consider testing moisturising creams with some sort of assay,” says Nouri. “These creams need to be tested first before they come to market.”
“Further studies are needed to determine the effects of topical applications of moisturising creams on sunlight-induced skin cancer in humans” say the researchers in the paper.
Also included in the paper are the results of a fifth, custom-made moisturiser, that the researchers asked Johnson & Johnson to make without mineral oil and sodium laurel sulphate. The researchers with Johnson & Johnson have patented the new cream, say Reuters, which had no significant effect on tumour formation or growth.