Cheers! Alcohol doesn't Cause Depression, Study Finds

Researchers from Australia say that there is no evidence that excess alcohol consumption can cause depression. The study was based on genetic mutations associated with lower alcohol tolerance. 

Clinicians have assumed that excess alcohol consumption might lead to depression. The latest study by Osvaldo Almeida from University of Western Australia and colleagues found no causal link between alcohol and depression.

"Even one of the diagnoses we have for depressive disorders - Substance Induced Mood Disorder - is a diagnosis where alcohol plays a role," Professor Almeida said.  "However, because of the observational nature of the association between alcohol and depression, and the risk of confounding and bias that comes with observational studies, it is difficult to be entirely certain that the relationship is causal."

People who drink alcohol might also smoke or have a poor diet, which might explain the risk of depression in this group, Almeida added.

The study included 3873 elderly men from the long-running Health in Men Study (HIMS). Researchers specifically looked for mutations associated with alcohol metabolism.

Our genetic make-up decides the limit of our alcohol tolerance. People with one particular genetic mutation have very low alcohol tolerance limit as the variation affects the enzyme that breaks down alcohol, researchers said. There are very few alcohol-related disorders seen in this group.

"Now, if alcohol causes depression, then a genetic variation that reduces alcohol use and alcohol-related disorders, should reduce the risk of depression.  The great advantage of looking at the gene is that this association is not confounded by any other factors - people are born like that," Almeida said in a news release.

The study showed that the genetic variant was associated with lower alcohol consumption levels but not with depression. Researchers said that the study also debunks the myth that drinking low to moderate levels of alcohol prevents depression.

According to researchers, other factors may explain depression in people with a history of alcohol-related problems and that alcohol wasn't solely responsible for depression.

Don't take the study as an excuse to go binge drinking. Researchers concur that alcohol can cause many other health problems. According to the National Institute on Alcohol Abuse and Alcoholism, drinking large amounts of alcohol can lead to impaired brain function, stroke, high blood pressure, fatty liver disease, and many types of cancers.

The study is published in the journal Molecular Psychiatry.