Social and family factors are involved in the amount of alcohol consumed in adolescence but genetic factors become more important in early adulthood.Most adolescents are exposed to and use alcohol before adulthood but as work, family and other social responsibilities increase during early adulthood most individuals decrease alcohol intake.In dizygotic twins the concordance for alcohol intake decreases during early adulthood while in monozygotic twins it remains stable, which indicates that genetic factors driving alcohol intake become more evident during early adulthood.

Alcohol Use is Almost Exclusively Influenced by Social and Familial Factors in Adolescence and Much More Strongly Influenced by Genetic Factors in Early Adulthood

From 1796 members of male-male twin pairs interviewed for their memory of the average number of days alcohol was consumed per month and the average number of consumed per day when drinking. The correlation between monozygotic twins stayed the same over time while the correlation between dizygotic twins while the same as monozygotic twins in adolescence decreased in early adulthood, indicating less of a genetic effect at that time. (Constructed from data in Kendler, K.S. et al. Arch Gen Psychiatry, 65: 674, 2008) ©2010 NBEP