There is a well known link between alcohol consumption and breast cancer risk, but can you reduce that risk by stopping or reducing your drinking?
Dr Mary Beth Terry addressed this question at the 2025 San Antonio Breast Cancer Symposium, an annual international research meeting that attracts over 9,000 participants each year. BCAC attended in person and online to bring back information of interest to New Zealanders experiencing breast cancer.
Dr Terry said that of the thousands of studies examining the association between alcohol consumption and breast cancer risk, only 17 asked the question ‘what happens if I stop or drink less?’
There is some limited evidence that reducing alcohol intake could reduce breast cancer risk. One study surveyed the drinking habits of over 4 million people (Yoo JE et al. 2022) for seven years and then recorded cancer incidence. 532 people were diagnosed with breast cancer during the study, allowing the researchers to examine how changes in drinking over a two year period might affect breast cancer risk.
This study showed that mild drinkers who quit significantly reduced their breast cancer risk compared to mild drinkers who did not change. Heavy drinkers who reduced their intake to a moderate level also reduced their risk, compared to those who continued with their heavy drinking. Interestingly, there were no other significant changes in breast cancer risk with changes in drinking behaviour. For example, heavy drinkers who became mild drinkers or even stopped drinking had no change in their risk. Moderate drinkers had the same risk whether they changed their drinking habits or not.
Dr Terry then explained that the association between alcohol and breast cancer risk is greater for oestrogen receptor positive (ER+) breast cancer. Alcohol is known to increase circulating concentrations of oestradiol and testosterone, but whether cessation alters these hormones is not known. Her analysis of several studies showed that, compared with continuing consumption, cessation was associated with a lower risk of ER+ breast cancer, but not ER- breast cancer (Terry et al. 2024).
Dr Terry also examined US breast cancer registry data to see if drinking behaviour might be linked to breast cancer in young women (under 40 years old), given the reported increase in diagnoses in this age group (Chen et al. 2024). She concluded that there was an association between moderate (1 drink per day) and heavy (2+ drinks per day) drinking and incidence of luminal A breast cancer in these women, but not other subtypes.
Other studies have shown that that binge drinking (4+ drinks in 2-3 hours) is associated with a greater risk of breast cancer than low-level drinking (1 drink per week) (White et al. 2017).
Clearly more research is needed, but based on current evidence Dr Terry concluded that you may reduce breast cancer risk by stopping drinking, but we need more data on the effects of reducing drinking, alcohol may be more strongly associated with the risk of ER+ breast cancer than other subtypes, and that binge drinking could be contributing to increased rates of breast cancer in young women.
Finally, it’s important to put this in a broader context. There are many risk factors for breast cancer – some of the strongest ones you can do nothing about – being female at birth, ageing, your genetics; others are ‘modifiable’ behaviours – eating, drinking, exercise - but changing these is a very personal decision based on your tolerance of risk and your priorities in life. Science-backed evidence can give you a sound basis for making these decisions.
19 December 2025
