Risk For Initiation of Substance Use as a Function of Age of Onset of Cigarette, Alcohol and Cannabis Use: Findings in a Midwestern Female Twin Cohort
Arpana Agrawal et al., "Risk for initiation of substance use as a function of age of onset of cigarette, alcohol and cannabis use: Findings in a Midwestern female twin cohort," Preventive Medicine 43, issue 2 (August 2006): 125-128.
What is the real "gateway drug"? This study of twins suggests that use of any drug by young people is an early warning signal that later use of other drugs is likely, with alcohol and cigarettes commonly coming before marijuana or other illicit drugs. A possible cause of this progression, the authors suggest, is environmental influences, including the illicit drug market.
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