Marriage and anticipation of marriage was found to reduce substance use in men by new research published in Psychological Medicine.

A number of previous studies have documented the relationship between marriage and reduced use of both illicit and licit substances in men. However, because previous studies relied on correlational designs, the direction of this relationship was unclear. While it is plausible that getting and staying married serves as a protective factor against using psychoactive substances it is also possible that men who are less likely to use substances are also more likely to get and stay married. In the current study, researchers intended to further investigate the nature of this relationship.

In a longitudinal study of 1,791 individuals from male-male twin pairs, researchers collected data on marital status, and the use of alcohol, tobacco, and cannabis during different periods of participants’ lives. This design allowed researchers to compare substance between participants, and between different periods within individual lives.

Analysis of the obtained data revealed that the use of alcohol and cannabis reduced significantly prior to marriage and during years right after marriage. This tendency to reduce drinking and cannabis consumption may be explained by the fact that social norms and expectation associated with the social role of a married man motivate individuals to change their habits and behaviors accordingly. Interestingly, substance use in men who cohabited with their partners resembled patterns of single rather than married men.

The use of tobacco did not decrease in the anticipation of marriage but it did decrease by the third year of marriage. Additionally, divorced and separated men were found to be heavier smokers than their married peers.

The study’ reliance on the twin sample allowed researchers to factor familial and individual factors like socioeconomic status, low level of education, parental history of substance abuse, antisocial traits, etc. into the analysis. The effect of marriage on substance use remained even after controlling for individual and familial factors that may underpin one’s likelihood of using psychoactive substances.

The study, “Marriage and Reductions in Men’s Alcohol, Tobacco, and Cannabis Use”, was authored by Jessica E. Salvatore, Charles O. Gardner and Kenneth S. Kendler.