Coffee
Drinking coffee is probably associated with a decreased risk of endometrial cancer. This association is seen with caffeinated and decaffeinated coffee.
For every cup of coffee a woman drinks per day, the risk of endometrial cancer decreases by about 5%. The decreased risk is likely to be seen only in women who are overweight or obese or in women who have never used menopausal hormone therapy (also known as hormone replacement therapy).
There are various ways in which coffee may affect the risk of endometrial cancer. This includes effects of caffeine on hormone levels, as well as effects of other chemicals in coffee on proteins in the blood that may contribute to development of endometrial cancer.
Green tea
Drinking green tea may be associated with a decreased risk of endometrial cancer.
Green tea contains antioxidants, which may play a role in stopping the growth of cancer-causing cells.
Black tea
There is no conclusive evidence that drinking black tea is associated with a decreased risk of endometrial cancer. Only a small number of studies have been conducted and these are of poor quality.
The difference in effect seen between green tea and black tea may be because some of the antioxidants found in green tea are removed when black tea is produced.