Alcohol is tied to far more than hangovers. A new systematic review published in Addiction finds that drinking contributes to a wide range of health harms, from injuries and infections to cancer, heart disease, liver disease and brain health risks.
The review does not present a new clinical trial. Instead, researchers analyzed the current evidence on alcohol and disease burden, including cohort studies and Mendelian randomization studies, a type of research that uses genetic variation to help examine possible cause-and-effect relationships. Their conclusion was broad but cautious: alcohol is a major contributor to disease and injury, and for many people, the health risks outweigh any possible benefits.
The review highlights more than 60 diseases and injuries that the World Health Organization’s current International Classification of Diseases lists as fully attributable to alcohol. Many of those conditions are linked to heavy drinking, including alcohol-related heart muscle disease, alcoholic liver disease and fetal alcohol syndrome.
But the review also points to several conditions where alcohol may play a partial role, including infectious diseases, some cancers, cardiovascular disease, type 2 diabetes, dementia, epilepsy, liver cirrhosis and pancreatitis. Alcohol can also increase the risk of injuries by affecting balance, reaction time and judgment, even at lower levels of intake.
That does not mean every risk works the same way, or that every harm is permanent. According to the review, some alcohol-related risks can decline when people cut back or stop drinking.
Short-term risks, such as injuries during intoxication, may fall quickly when drinking stops. Alcohol can temporarily weaken the immune system, and some immune effects may improve after abstinence, although long-term heavy drinking can cause more lasting damage. Some cardiovascular effects may improve within days to weeks after stopping drinking, while chronic conditions such as cirrhosis and heart disease may not fully reverse.
The researchers also note that brain damage related to heavy drinking may partially improve with long-term abstinence, though risks such as dementia can remain.
Senior author Dr. Jürgen Rehm, senior scientist at the Canadian Centre for Addiction and Mental Health, said the relationship between alcohol and heart health remains one of the more complicated areas of the evidence.
“Even though we now know a lot about alcohol’s effects on health, it is still controversial whether a little drinking is good for your heart,” Rehm said. “When examining both cohort studies and Mendelian randomisation studies, and all their potential strengths and biases, we conclude that there is not enough evidence to rule out a beneficial effect of drinking on ischaemic heart disease and ischaemic stroke.”
That caveat is important. The review does not say alcohol is harmless for the heart. Alcohol has been linked to several cardiovascular problems, including high blood pressure, cardiomyopathy, atrial fibrillation and stroke. Instead, the authors argue that any possible benefit for specific heart-related outcomes must be weighed against alcohol’s wider health harms.
Sinclair Carr, the review’s first author and a PhD candidate at the Harvard T.H. Chan School of Public Health, summarized the findings more directly.
“Our review of the current evidence on alcohol's effects on health leads to a cautious but clear conclusion: alcohol is a major cause of disease and injury, and its harms outweigh any potential benefits,” Carr said.
For everyday drinkers, the findings do not offer a one-size-fits-all rule. Risk depends on how much a person drinks, how often they drink, whether they binge drink, their health history and the setting in which alcohol is consumed. But the review does suggest that reducing alcohol intake may lower some health risks, even when past drinking has already caused damage.
The research was supported by the National Institute on Alcohol Abuse and Alcoholism of the National Institutes of Health.