Green tea may help protect against autoimmune disease, Medical College of Georgia researchers say.
Researchers studied an animal model for type I diabetes and primary Sjogren's Syndrome, which damages the glands that produce tears and saliva.
They found significantly less salivary gland damage in a group treated with green tea extract, suggesting a reduction of the Sjogren's symptom commonly referred to as dry mouth. Dry mouth can also be caused by certain drugs, radiation and other diseases.
Approximately 30 percent of elderly Americans suffer from degrees of dry mouth, says Dr. Stephen Hsu, a researcher in the MCG School of Dentistry and lead investigator on the study. Only 5 percent of the elderly in China, where green tea is widely consumed, suffer from the problem.
"Since it is an autoimmune disease, Sjogren's Syndrome causes the body to attack itself and produce extra antibodies that mistakenly target the salivary and lacrimal glands," he says.
There is no cure or prevention for Sjogren's Syndrome.
Researchers studied the salivary glands of the water-consuming group and a green tea extract-consuming group to look for inflammation and the number of lymphocytes, a type of white blood cells that gather at sites of inflammation to fend off foreign cells.
The group treated with green tea had significantly fewer lymphocytes, Dr. Hsu says. Their blood also showed lower levels of autoantibodies, protein weapons produced when the immune system attacks itself, he says.
Researchers already know that one component of green tea , EGCG , helps suppress inflammation, according to Dr. Hsu.