Research has found that both drinking alcohol and taking hormone replacement therapy (HRT) can increase breast cancer risk. A large study combined the two by looking at how drinking alcohol while taking HRT affected breast cancer risk.
The study looked at the drinking habits and HRT use of more than 5,000 Danish women for 20 years. The researchers found:
- Drinking alcohol while not taking HRT didn't really affect breast cancer risk.
- Postmenopausal women who were taking HRT AND drank 1 or 2 alcoholic drinks per day had a breast cancer risk that was 3 times higher than women who didn't drink and didn't take HRT.
- Postmenopausal women who were taking HRT AND had more than 2 alcoholic drinks per day had a breast cancer risk that was 5 times higher than women who didn't drink and didn't take HRT.
Drinking alcohol increases estrogen levels. It's possible that the extra estrogen from drinking combined with the estrogen in HRT caused the dramatic increases in risk in this study.
When researchers look at breast cancer risk factors, they usually focus on 1 factor. This research is different because it looked at how 2 risk factors might combine to have an even larger effect on risk. According to this study, there appears to be an association between regularly drinking alcohol while taking HRT and increased breast cancer risk. And this increase in risk is higher than it would be by drinking alcohol alone or taking HRT alone.
More research needs to be done to better understand the link between drinking, taking HRT, and increased risk. In the meantime, here are some things to consider:
- Limiting your intake of alcohol to 4 or fewer drinks per week is good for your overall health and will probably lower your breast cancer risk.
- Taking HRT can increase your breast cancer risk, but HRT may be right for you if severe hot flashes or other menopausal symptoms are seriously affecting your quality of life. If you're taking HRT, try to do everything you can to minimize your breast cancer risk.
- Talk to your doctor about using estrogen-only HRT, which increases breast cancer risk less than combination HRT.
- Take HRT for the shortest time possible.
- Consider not drinking alcohol while on HRT.
For more information on how to keep your breast cancer risk as low as it can be, visit the breastcancer.org Lower Your Risk section.