Green Tea Ingredient Could Fight Leukemia

Scientists found that high doses of a chemical found in the drink could kill cancer cells and reduce symptoms of the disease.

Researchers have been looking at the anti-cancer properties of green tea since the 1970s, when a study showed that countries which consumed large amounts of the herb tended to have lower levels of the disease.

 

In 2004 studies in mice showed that the active ingredient in the tea, epigallocatechin gallate (EGCG), could kill leukaemia cells.

Preliminary results now suggest that the chemical could have the same effect on patients suffering from a type of leukaemia, called chronic lymphocytic leukaemia (CLL).

The researchers believe that the treatment would not be potent enough on its own, but could make other anti-cancer medications more powerful.

Dr Tait Shanafelt, from the Mayo Clinic in Minnesota, said: "We found not only that patients tolerated the green tea extract at very high doses, but that many of them saw regression to some degree of their chronic lymphocytic leukaemia." CLL is a type of cancer in which the bone marrow makes too many lymphocytes, a type of white blood cell.

The treatment reduced the number of lymphocytes in one in three patients, according to the findings published online in the Journal of Clinical Oncology.

The cancer can also cause patients to suffer from enlarged lymph nodes, a part of the body which is crucial to the immune system where white blood cells collect.

Most of the patients in the trial who suffered from enlarged lymph nodes saw them reduced by 50 per cent or more after taking the extract, the study also found.

Researchers gave 33 patients between 400 and 2,000 milligrams of the extract twice a day.

Many cases of CLL progress slowly, and often treatment involves an early stage of "watchful waiting" before patients are given strong treatments.

Researchers hope that EGCG could stabilize the disease for many patients in the early stage or improve the success rates of other therapies like chemotherapy.

Each year around 7,000 people in the UK are diagnosed with leukaemia and about 4,300 die.