Does early exposure to caffeine promote smoking and alcohol use behavior? A prospective analysis of middle school students

Abstract

Caffeine may promote early use of other types of substances among middle school-aged adolescents.

Cigarette smoking and personality: Investigating causality using Mendelian randomization

“…Coffee consumption is also surprisingly common-41% of young people in this study report that they drink coffee on a typical day. As these characteristics may be specific to this particular sample, it would be useful to attempt replication of Kristjansson et al's [1] findings in other (non-US-based) samples.…”

“…It is worth noting that Kristjansson et al [1] report a somewhat high intake of caffeine. In 6th grade (aged 11-12 years) and 7th grade (aged~12-13), the average caffeine intake was 253 mg/day and 236 mg/day, respectively.…”

“…This was in an adult population, however, and MR may not be well suited to detect effects acting during adolescence only, because genetic variants capture lifetime exposure. If well-powered genome-wide association studies of e-cigarette use become available, it would also be possible to explore the suggestive effect of e-cigarette use on caffeine intake found by Kristjansson et al [1]. Another informative method for causal inference is the use of negative controls.…”

Commentary on Kristjansson et al. (2018): Caffeine use during early adolescence as a possible risk factor for initiation of smoking and alcohol use

“…Kristjansson et al . present a well‐designed study that followed adolescents from 6th to 7th grades, monitoring their intake of caffeine and their use of conventional cigarettes, e‐cigarettes and alcohol. Using cross‐lagged path models, the authors attempted to test causal effects from caffeine to other substance use, and from other substance use to caffeine.…”

“…It is worth noting that Kristjansson et al . report a somewhat high intake of caffeine. In 6th grade (aged ~11–12 years) and 7th grade (aged ~12–13), the average caffeine intake was 253 mg/day and 236 mg/day, respectively.…”