Researchers at the Norwegian University of Science and Technology and the University of Bergen said it has long been recognized that excessive alcohol consumption can lead to poor physical and mental health. The researchers -- using data from the Nord-Trondelag Health study that provided information on the drinking habits and mental health of more than 38,000 people -- showed those who reported drinking no alcohol during a two-week period were more likely than moderate drinkers to report symptoms of depression.
People who called themselves "abstainers" were at the highest risk of depression.
Other factors, such as age, physical health problems and number of close friends could explain some, but not all of this increased risk.
The authors also had access to reported levels of alcohol consumption 11 years prior to the main survey.
The study, published in Addiction journal, showed that 14 percent of current abstainers had previously been heavy drinkers, but this did not explain all of the increased risk of depression among abstainers.
The authors conclude that in societies in which some use of alcohol is the norm, abstinence may be associated with being socially marginalized, or with particular personality traits that may also be associated with mental illness.