Vaping has become increasingly prevalent among adolescents and young adults despite growing evidence of its adverse physical and mental health consequences. Research suggests that an earlier age of vaping onset is associated with more frequent vaping later in life, although little is known about whether health beliefs about vaping moderate this relationship.

The present study examined the association between age of vaping onset and current vaping frequency among young adults in the Netherlands and whether positive and negative health beliefs about vaping moderated this relationship. Data were collected through a survey among participants aged 16 to 25 years. After applying the inclusion criteria, 241 participants were included in this study. A simple linear regression analysis was conducted to examine the association between age of vaping onset and vaping frequency. Moderation analyses were conducted using PROCESS Model 1.

Results showed that an earlier age of vaping onset was associated with higher current vaping frequency, explaining 11.3% of the variance in vaping frequency, with a small to medium effect size. Neither positive nor negative health beliefs moderated the relationship between age of vaping onset and vaping frequency. These findings confirms that age of vaping onset is an important predictor of later vaping behavior, however, in this study health beliefs appear to not play a  role in the association between vaping onset and vaping frequency. These findings highlight the importance of delaying vaping onset during adolescence as a potential target for prevention programs.