Can Melatonin Cause Breast Cancer? Can Melatonin Cause Breast Cancer? Melatonin is a hormone your body makes to help you sleep. People often take extra melatonin from pills if they have trouble sleeping. It’s common to wonder if taking these pills can lead to health problems, like breast cancer. There has been talk about whether melatonin … Continue reading Can Melatonin Cause Breast Cancer?