A lower IQ is clearly associated with greater and riskier drinking among young adult men, a research has found.
"It may be that a higher IQ results in healthier lifestyle choices," said corresponding author for the study Sara Sjolund, doctoral student at Karolinska Institutet in Stockholm, Sweden.
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, Sjolund added.
The researchers analysed 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," Sjolund said.
The researchers noted that results may vary among cultures and countries.
"Poor performance on IQ tests tend to go along with other disadvantages, for instance, poorer social background and emotional problems, which may explain the association with risky alcohol consumption," Daniel Falkstedt, assistant professor at Karolinska Institutet said.
"In reality, other differences of importance are likely to exist among the men, which could further explain the IQ-alcohol association," Falkstedt said.
The study is forthcoming in the journal Alcoholism: Clinical and Experimental Research.