Evidence tells us alcohol causes cancer and drinking alcohol increases a person’s risk of developing breast cancer.1,2,3
Breast cancer symptoms
Cancer Research UK states that you should see a doctor if you have noticed:
A change in the size, shape or feel of a breast
A new lump or thickening in a breast or armpit
Skin changes on such as puckering, dimpling, a rash or redness of the skin
Fluid leaking from a nipple when you aren't pregnant or breastfeeding
Changes in the position of a nipple
Most often these symptoms are caused by other medical conditions and are not necessarily symptoms of breast cancer, but if you experience any of them, it is important to get them checked by a doctor or another qualified member of your GP's team. Please visit the Cancer Research UK website for more information about the early symptoms of breast cancer.
Understanding breast cancer risks from alcohol
Globally, cancer is the fifth largest cause of alcohol-related deaths4 yet few people make the connection between alcohol and cancer. Breast cancer is the most common cancer among women5 in the UK and while drinking alcohol doesn’t mean you will get breast cancer there is evidence to suggest that:
the risk of developing alcohol-related cancers, including breast cancer, increases significantly if drinking more than an average of one alcoholic drink a day – or one unit, which is equivalent to about one small (125ml) glass of wine;6,7,8
the more you drink over a lifetime the higher your risk of developing breast cancer becomes.9
See if your drinking could be harming your health
How does alcohol increase your risk of developing breast cancer?
The ways in which alcohol increases the risk of developing breast cancer are not fully understood but probably include:
The body breaks down alcohol into a substance called acetaldehyde which can cause changes in our DNA. This can trigger a response in the body which leads to cancerous cells developing.10,11
Alcohol increases levels of female hormone oestrogen – high levels of oestrogen can cause a cancer cell continually to multiply.12
Remember, drinking alcohol even in very modest amounts for several years increases a person’s risk of developing breast cancer, and is also linked to six other types of cancer in men and women.13
Other breast cancer risk factors
There are many other factors that increase a person’s risk of developing breast cancer, some of which we cannot control, such as:
Other factors in addition to alcohol, include being overweight, which is known to increase breast cancer risk.14 Recent evidence suggests that smoking, including passive smoking, may also increase the risk of developing breast cancer in some people, particularly in women after the menopause.15
Cancer Research UK estimates that 23% of breast cancers are preventable, and that includes the 8% (or one in 13) of cases due to alcohol.16 Learn more about the risk factors from Cancer Research UK here.
The potential harms from alcohol specific to women
How to reduce the risk of developing breast cancer from drinking alcohol
Just drinking a few drinks each week increases your risk of breast cancer.17 If you do choose to drink alcohol, it is best to drink within the UK Chief Medical Officers’ (CMO) low risk drinking guidelines and to spread your drinking throughout the week, incorporating several drink-free days.
As well as reducing your drinking, being active, maintaining a healthy weight, not smoking and eating a balanced diet, can all help to reduce your risk of developing several types of cancer, including breast cancer.
All women in the UK who are aged 50-70 and are registered with a GP are automatically invited for breast screening every three years. Breast screening is a type of X-ray test called a mammogram which can detect cancers when they are too small to see or feel. After 70, women can choose to continue three-yearly breast screening.
For more information about breast screening in the UK, follow the links below.
Male breast cancer
Breast cancer is rare in men and more research is needed to understand the link between alcohol and the increased risk of developing it. However, advice for men who choose to drink is the same as for women; not regularly drinking more than the CMOs’ low risk guidelines will help reduce the risk of developing male breast cancer, although regularly drinking even modest amounts of alcohol is linked with increased risk.
More about alcohol and men's
N.B: In the evaluation of the carcinogenicity of alcohol (p.472), IARC state that alcohol causes breast cancer and classifies it as a group 1 carcinogen.
N.B. The specific data are given in the electronic supplementary material (specifically: ‘Cancer attributable to risk factors, UK 2015 - Final Supplementary Material F’), which indicates, in 2015, the fraction of breast cancer cases attributable to alcohol in the UK was 8.1% in women, which is 8 cases in every 100 cases or 1 case in every 12.5 cases. For ease of understanding, we have ‘rounded up’ to 1 in 13 cases.