The “gateway” effect of e-cigarettes may be explained by a genetic liability to risk-taking.

It is still prudent public health policy to minimise youth uptake of e-cigarettes, even if their
use does not lead to cigarette smoking. However, this does not require a sales ban on nicotine
vaping products to adult smokers. More proportionate regulatory policies that have reduced
the uptake of cigarette smoking among youth could also minimise youth uptake of e-cigarettes,
namely, setting age limits on purchase, restricting the number and types of outlets where e-cigarettes
can be sold, and prohibiting the marketing and advertising of e-cigarettes. These policies
would allow adult smokers to access e-cigarettes for smoking cessation or as a lower risk
substitute for cigarette smoking [6].

hall W, Chan G. The “gateway” effect of e-cigarettes may be explained by a genetic liability to risk-taking. PLoS medicine. 2021;18(3):1. doi:10.1371/journal.pmed.1003554