Research on Green Tea and Cancer

It is often asked if tea can prevent cancer but the short answer to that question is unfortunately in the negative. However, there are many studies that give weight to the belief that it certainly helps. Lung, prostate, breast, bladder and other cancers have all been the subject of intense research over the past fifty or so years. Many if not all of them have been favorably influenced by compounds commonly found in tea. One of the most promising of recent finds is the identification of an antioxidant called EGCG or epigallocatechin gallate.

Antioxidants have long been believed to help hinder or slow the growth of cancer cells and tumors. U.S. National Cancer Institute studies have shown that catechins, a component of tea, inactivate oxidants, reducing the number and size of tumors. EGCG may be one of the reasons.

Research on Green Tea and Cancer

Patients in a recent Japanese study at Kyushu University drank two to three cups of green tea per day, rich in EGCG. The researchers found that human lung cancer cells grew more slowly when they did. In test tube studies, EGCG inhibited an enzyme that cancer cells require in order to grow and divide.

A British and Spanish co-study reinforces the idea. Researchers at the University of Murcia and the John Innes Center in England found that EGCG in green tea prevented cancer cells from growing large enough to divide. The mechanism is believed to be the result of EGCG's ability to bind to the specific enzyme (dihydrofolate reductase) needed.

At the University of Southern California researchers studying breast cancer found similar results. Green tea drinkers had a lower incidence of tumors, even adjusting for other factors such as family history, exercise and diet. Here, one important factor appears to be the ability of certain compounds in tea to inhibit the growth of blood vessels.

Cancer cells, just like any other, need nutrients from blood in order to grow. They stimulate the growth of blood vessels in order to supply themselves. Tea inhibits that ability, according to a joint study by the University of California and the University of Texas.

Other studies show that drinking five cups per day can help boost the immune system, providing the body with an ability to combat emerging cancer cells. Alkylamine antigens are thought to be responsible. Ingesting them by drinking tea produces a more vigorous response against tumors.

Another study examined bladder cancer. An extract made from green tea altered the actions of actin, a structural protein needed by cancer cells to function. A process called 'remodeling' allows cancer cells to invade nearby healthy tissue. A compound made from green tea modified the cancer cell's ability to carry out this process.

While the specific mechanisms are still a matter of ongoing research, a cluster of studies all point to tea's ability to assist in preventing cancers. There are no known downsides to consuming a few cups per day, either. It's a smart choice.