What does alcohol do to your biological age?

Alcohol accelerates multiple ageing processes simultaneously. Chronic heavy drinking disrupts the gut microbiome, damages the gut wall, and causes low-grade inflammation throughout the body. That inflammation contributes to liver disease, brain damage, and deterioration of multiple organs.

In the liver, alcohol activates a molecular cascade that leads to oxidative stress and cell death. This mechanism has been studied in both human liver tissue and animal models, and provides a biological explanation for why heavy drinking is so harmful to the liver.

The brain is a separate risk area. Animal research shows that alcohol lowers the production of a specific protein in the brain's fear and emotion centre, which can cause or worsen depressive symptoms. For older people there is an added concern: the effects of drinking pile on top of the cognitive decline that already accompanies ageing. Research specifically focused on older people is scarce, but the indications are consistently negative.

Ageing itself already brings chronic low-grade inflammation and a slower immune system. Alcohol amplifies these processes, making older people more susceptible to alcohol-related diseases than younger people. For older women there is an additional risk: the hormonal axes that regulate stress and reproduction are already altered by menopause and ageing, and alcohol can cause extra damage to the brain as a result. Exactly how much is still insufficiently studied.

Finally, there is a genetic nuance: people with a specific variant in the gene that breaks down alcohol (common in East Asian populations) accumulate a toxic breakdown product even at low amounts of alcohol. In these individuals, even moderate drinking leads to gut damage and oxidative stress. Alcohol also rarely acts in isolation: the combination with smoking, poor diet, and ageing makes the total harm greater than any of those factors alone.