Moisturizers May Cause Skin Cancer

Millions of people use moisturizers to treat their dry skin that causes severe itching. But, a new study published by researchers at Rutgers University in New Jersey has expressed doubt that moisturizers can spur skin cancers.

In their study, the researchers found a clear link between some common moisturizing creams and the development of skin cancerdefine in mice.

To reach their findings, 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, and colleagues tested four highly common skin moisturizers on mice.

The researchers first applied skin creams on genetically altered hairless mice, and then exposed them to high levels of cancer-causing UV rays. What Conney’s team found was quite alarming, as the moisturizers made the skin of mice that were treated with skin moisturizers more sensitive, and this group of mice also showed an increased rate of tumor formation.

Conney and colleagues found that rates of non-melanoma skin cancers among mice given the moisturizers increased between 24 and 95 percent compared to control mice not treated with creams.

"This was unexpected. We really did not expect to see the tumor-promoting activity of these creams," Conney said.

The four creams analyzed in the study were Dermabase, manufactured by Paddock Laboratories Minneapolis, Minnesota; Dermovan, made by Healthpoint Ltd in Fort Worth, Texas; Eucerin Original Moisturizing Cream, made by Beiersdorf Inc. in Wilton, Connecticut; and Vanicream, made by Pharmaceutical Specialties, Inc. in Rochester, Minnesota.

The researchers rubbed the aforementioned moisturizer creams into the animals' skin five days a week for 17 weeks that produced the following results:

Eucerin increased the total number of tumors by 24%.
Vanicream increased the total number of tumors by 58%.
Dermabase increased the total number of tumors by 69%.
Dermovan increased the total number of tumors by 95%.

Conney’s team identified two ingredients previously linked to skin irritation (sodium lauryl sulfate) and tumor promotion (mineral oil) in the moisturizers that appear to enhance tumor growth, and asked Johnson & Johnson to make them a "custom blend" moisturizer without the aforesaid ingredients. When the researchers repeated the experiments with the custom blend cream the cancer rates dropped sharply.

"We took out a couple of ingredients and made a cream that turned out to be non-tumorigenic," Conney said. "We really don't know what ingredients in these creams are doing that."

"There is a need to have the various companies test their creams to see whether or not there is a problem," he suggested.

Coney’s findings were published in the Aug. 14 issue of the Journal of Investigative Dermatology, part of the Nature Publishing Group in Britain.

Skin cancer is the most common cancer in humans. This condition generally develops in the epidermis (the outermost layer of skin), so a tumor is usually clearly visible. Sun exposure is the major risk factor for the development of skin cancer.

Malignant melanoma is the most lethal form of skin cancer. This form of skin cancer can be fatal if not treated early. Surgical removal is the treatment of choice, and sun protection has been shown to dramatically reduce the incidence of this illness. Non-melanoma skin cancer is very common in humans, and is curable surgically.