How alcohol causes cancer

Alcohol is a Group 1 carcinogen. This is the highest classification available – the same as tobacco smoking or asbestos – and means that it is an acknowledged cause of cancer.

It is estimated that in 2010, more than 3,200 cases of cancer were attributable to long-term alcohol consumption each year in Australia. 

There is convincing evidence that drinking alcohol increases the risk of cancers of the mouth, throat (pharynx and larynx), oesophagus, bowel, liver and female breast after menopause. There is probable evidence that alcohol increases cancers of the stomach and female breast cancer before menopause.

There are a number of ways that may explain how alcohol causes cancer, such as:

  • The pure alcohol (ethanol) in alcoholic drinks being converted into a toxic chemical called acetaldehyde, which damages our DNA and stops cells from repairing
  • Ethanol may also cause direct tissue damage by acting as a solvent for other carcinogens
  • Increasing the level of hormones such as oestrogen, which are linked to breast cancer
  • Altered folate metabolism, affecting cell function

Being above a healthy weight is also linked to 13 types of cancer, including the oesophagus, pancreas and bowel. Drinking alcohol can increase the risk of being above a healthy weight, by:

  • Having extra kilojoules that we drink but don’t make us full
  • Being more likely to store food we eat after drinking as fat, because our body is prioritising breaking down the alcohol

Lifestyle factors such as smoking, poor oral hygiene and poor diet may also increase the risk of cancers caused from drinking alcohol regularly. For example, if you smoke and drink, the risk of a cancer developing is greater than these risk factors in isolation.


Drinking less alcohol will reduce your risk of cancer. Drink Less, Live More.