“My mum does not want me to drink alcohol until I’m 18 and she’s trying to scare me by saying that it causes all of these problems. One of the ones she keeps warning me about is that alcohol causes breast cancer. That’s not true is it? If it was there would be so many people dying from the disease.”
Alcohol use increases the risk of developing a range of cancers, particularly cancers of the mouth, throat, oesophagus, stomach, bowel, liver and, yes, just as your Mum said, the breast. Although very few people are aware of it, it doesn’t matter what type of alcohol you drink – the risk of cancer increases with every alcoholic drink you have. When it comes to breast cancer, research has found that having just one drink per day can increase the risk of developing the disease by 5-15% compared to those women who do not drink at all.
Breast cancer is one of the main causes of death in women worldwide, with over 2 million new cases detected annually worldwide. It’s the fifth most common cancer death, with 685,000 deaths every year. In women, one in four cancer cases and one in six cancer deaths are due to breast cancer. It’s the most common cancer in women in Australia (apart from non-melanoma skin cancer), with 53 people diagnosed with the disease every day. It’s estimated that one in 1 in 8 females and 1 in 667 males will be diagnosed by the time they are 85. Some people are at greater risk of getting breast cancer than others and sadly, there is little they can do about those risk factors, such as being female, their age, family history or late menopause. However, the amount of alcohol you choose to drink is something that you can change to reduce the risk.
Alcohol is thought to be the cause of between 5-11% of all breast cancer cases. But even though research has found that drinking even small amounts of alcohol is linked with an increased risk of breast cancer it’s still not completely clear why this is the case. Research is still being conducted to find out whether patterns of drinking could play a role. One study of a cohort of women with a family history of the disease, found that ever binge drinking or ever having blacked out while drinking were factors associated with increased breast cancer risk. Other studies, however, found that even among people who drank lightly there was evidence of increased risk.
We do know that alcohol limits the liver’s ability to control estrogen levels in the body. This can lead to increased estrogen levels which we know is linked to breast cancer in postmenopausal women. In addition, when the liver breaks down alcohol a toxic chemical called acetaldehyde is produced. This is a carcinogen and usually breaks down quite quickly but if you drink too much, too fast this chemical starts to build up, and is one of the main reasons why drinkers can feel sick or nauseous. Although production of acetaldehyde from alcohol mainly occurs in the liver, it also occurs in breast tissues. There’s now increasing evidence that acetaldehyde can damage DNA, converting normal cells into cancer.
This is not as simple as if you drink alcohol you’ll get breast cancer. Like almost everything in life, it’s far more complicated than that. It’s important to remember, however, that when it comes to breast cancer risk, no amount of alcohol is considered safe.
First published: February 2018
Reviewed and updated: February 2025
