Green tea could hold promise as a new treatment for skin disorders such as psoriasis and dandruff, Medical College of Georgia researchers say.

Researchers studied an animal model for inflammatory skin diseases, which are often characterized by patches of dry, red, flaky skin caused by the inflammation and overproduction of skin cells. Those treated with green tea showed slower growth of skin cells and the presence of a gene that regulates the cells’ life cycles.

“The traditional treatment of ultraviolet light and medication, while it can control the lesions and be used long term, may cause squamous cell carcinoma – the second most common form of skin cancer,” Dr. Hsu says. “Some of the most effective anti-dandruff shampoos also have carcinogens in them. While the U.S. Food and Drug Administration allows that in small amounts, the bottom line is that we don’t know the long-term effects of using those products continuously.”

Animal models treated with green tea also showed reduced levels of proliferating cell nuclear antigen, a gene expressed when skin cells multiply. In psoriasis, the gene is over-expressed and speeds production of skin cells. “Before treatment, the antigen, PCNA, was present in all layers of the skin,” Dr. Hsu says.

“Typically, PCNA is only found in the basal layer, the innermost layer where skin cells continually divide and new cells push the older ones to the skin surface, where they eventually slough off. After being treated with green tea, the animal models showed near-normal levels of PCNA in only the basal layers.”