A lower IQ is associated with greater and riskier drinking among young adult men, according to a recent study.

Although several studies have shown an association between intelligence and various health-related outcomes, the research on cognitive abilities and alcohol-related problems has been inconsistent.

"Previous results in this area have been inconsistent," said Sara Sjölund, a doctoral student at the Karolinska Institutet in Stockholm, Sweden as well as corresponding author for the study. "In two studies where the CAGE questionnaire - a method of screening for alcoholism - was used, a higher cognitive ability was found to be associated with a higher risk for drinking problems. Conversely, less risk has been found when looking at outcomes such as, for example, International Classification of Diseases diagnoses of alcoholism, alcohol abuse, and dependence."

For the study, Sjölund and her colleagues analyzed data collected from 49,321 Swedish males born during 1949 to 1951 and who were conscripted for Swedish military service from 1969 to 1971. IQ results were available from tests performed at conscription, and questionnaires also given at conscription provided data on total alcohol intake (consumed grams of alcohol/week) and pattern of drinking, as well as medical, childhood and adolescent conditions, and tobacco use. Adjustments were made for socio-economic position as a child, psychiatric symptoms and emotional stability, and the father's alcohol habits.

"We found that lower results on IQ tests in Swedish adolescent men are associated with a higher consumption of alcohol, measured in both terms of total intake and binge drinking," said Sjölund. "It may be that a higher IQ results in healthier lifestyle choices. Suggested explanations for the association between IQ and different health outcomes, could be childhood conditions, which could influence both IQ and health, or that a socio-economic position as an adult mediates the association."

Results will be published in the March 2015 online-only issue of Alcoholism: Clinical & Experimental Research and are currently available at Early View.