Regular drinking of alcohol may promote the formation and growth of cancerous cells and tumors that are sensitive to hormones in the breast of postmenopausal women.

This study was carried out to confirm the detrimental effect of alcohol consumption on breast cancer risk. Researchers matched alcohol drinking habit with breast cancer diagnosis among 87,724 postmenopausal women who enrolled in the Women's Health Initiative Observational Study. 

Researchers found out the greater the frequency and amount of alcohol consumed, the higher the risk of breast cancer, specifically the hormone-sensitive type, in postmenopausal women. The data from this study indicate that fondness of alcohol may fuel the development of hormone-sensitive type of breast cancer in postmenopausal women.