Alcohol can cause irreversible genetic damage to the body’s reserve of stem cells, according to a study that helps explain the link between drinking and cancer. The study using genetically modified mice revealed that DNA damage was exacerbated when mice lacked the first tier of defence – a protective enzyme called aldehyde dehydrogenase 2 (ALDH2), which prevents potentially toxic build-ups of acetaldehyde.

In mice that lacked both natural defences against alcohol, their ability to produce fresh blood was completely destroyed after being given diluted alcohol for ten days. Sequencing the genome of the stem cells showed that their DNA had been scrambled to the point that the cells no longer functioned.