Green Tea Found to Be a Dandruff Slayer

That famous healthy British skin has its secret: green tea. Now, green tea could lead to a new treatment for skin disorders like psoriasis and dandruff, as found by a team at the Medical College of Georgia.

The researchers performed tests on an animal model to study the inflammatory skin diseases, characterized by patches of dry, red, flaky skin due to inflammation and overproduction of skin cells. Animals treated with green tea displayed slower growth of skin cells and the activation of a gene controlling the cells' life cycles.

"Psoriasis, an autoimmune disease, causes the skin to become thicker because the growth of skin cells is out of control. In psoriasis, immune cells, which usually protect against infection, instead trigger the release of cytokines, which causes inflammation and the overproduction of skin cells," said lead researcher Dr. Stephen Hsu, an oral biologist in the MCG School of Dentistry.

Lupus is another autoimmune disease with similar side effects, like skin lesions, and dandruff. Green tea is known to inhibit inflammation, by regulating the expression of Caspase-14, a protein that controls the life cycle of a skin cell. "That marker guides cells by telling them when to differentiate, die off and form a skin barrier. In people with psoriasis, that process is interrupted and the skin cells don't die before more are created and the resulting lesions form.", Hsu said.

Lab animals treated with green tea also presented low levels of proliferating cell nuclear antigen, a compound indicating active skin cell multiplication. In psoriasis, the higher amounts of antigen boost the proliferation of skin cells.

"Before treatment, the antigen, PCNA, was present in all layers of the skin. 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.", said Hsu.

"This research is important because some treatments for psoriasis and dandruff can have dangerous side effects. 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. 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.", he added.

Green tea would be a healthy alternative, but its compounds are so active that they are broken down too rapidly in contact with other ingredients and dissolve into water, which cannot penetrate through the skin's barrier. "Researchers are looking for a balanced formula that can dissolve in fats, which can permeate the skin. There are no cures for autoimmune diseases. But it is possible that this is a non-toxic way to regulate them. We need further study - on humans - to determine the full effects", Hsu said.