Posted on July 21, 2023 By Colin
ONE OF THE MOST COMMON arguments against vaping is that it will increase youth smoking (the 'gateway theory'). However, there is now good evidence that this is not true. In fact, vaping is REDUCING smoking rates in young people.
Young people who try vaping are also more likely to try smoking because they share risk factors that lead to both behaviours ('common liability'). But this does not mean that vaping caused them to take up smoking. Teens who vape are also more likely to take other risks, such as smoking, drinking alcohol, drink driving, using illicit drugs and having unsafe sex. Vaping does not cause these behaviours either.
Some young non smokers who try vaping may go on to try smoking. However, far more move in the other direction, ie many young smokers or would-be smokers turn to vaping instead, a far safer alternative.
Overall vaping reduces smoking in young people and has a net beneficial effect on population health
The gateway myth is a disingenuous tactic used by Health Minister Mark Butler, the Australian Medical Association, the NHMRC, Emeritus Professor Simon Chapman, Professor Emily Banks, Cancer Council Australia and other vaping opponents to justify their dislike for vaping.
There are 5 strands of scientific evidence demonstrating that vaping is not leading to smoking.
Studies show that young people who experiment with vaping are three times more likely to also try smoking. However, young people who experiment with vaping are different to kids who don’t vape. Kids who try vaping are more likely to use other drugs, have friends who vape or smoke, have mental illness, parents who smoke, come from lower socio-economic backgrounds, have lower education etc. These 'shared risk factors' put them at risk of experimenting with both vaping and smoking.
Studies that allow for these differences between groups have found that the increased risk of smoking in teens who vape (compared to teens who don't vape) dramatically reduces or disappears. For example, a rigorous study by Kim 2019, adjusted for 14 shared risk factors and concluded that:
The apparent relationship between e-cigarette use and current conventional smoking is fully explained by shared risk factors, thus failing to support claims that e-cigarettes have a causal effect on concurrent conventional smoking among youth
Other studies that account for a comprehensive range of shared risk factors have found the same result, for example, Sun 2021 and Cheng 2020.
The gateway theory predicts that vaping will increase smoking rates in young people. However, we are seeing the opposite of this. In countries where vaping is readily available such as the UK, US and New Zealand, the decline in youth smoking rates has accelerated.
For example, since vaping became popular in the US in 2013, smoking by high schoolers fell from 10% to 1.9% (dark blue in the graph).
Graph credit: Brad Rodu, Tobacco Truth
Other studies have found similar results. (Levy 2019; Meza 2021; NHS Digital UK 2022; ASH NZ 2022
2 recent studies from the US and UK confirmed the absence of a gateway effect:
Many studies have found that vaping and smoking are substitutes and that vaping is diverting young people AWAY FROM smoking.
Other research studies (natural experiments) have found that youth smoking rates increase when access to vaping is restricted. This has been demonstrated for
These findings confirm that vapes and smokes are substitutes. Reducing access to vaping increases the uptake of deadly smoking.
There is growing evidence that teens who vape first (before smoking) are less likely to smoke later, compared to those who smoke first (Shahab 2021; Legleye S 2021; Mus 2023) Other studies have found no evidence that vaping first increases smoking uptake (Chyderiotis 2020; Stanton 2023)
An analysis of 84 longitudinal studies of vaping by adolescent non-smokers found major methodological design errors in the study design. The analysis concluded that the flaw resulted in an overestimation of any gateway effect from vaping to smoking. The findings support diversion by vaping away from smoking in adolescents. (Dautzenberg 2023)
Harsh restrictions to discourage youth vaping based on the flawed gateway theory also lead to reduced access to vaping for adult smokers. Vaping should be readily available as a quitting aid and draconian restrictions reduce its uptake send a false signal to smokers that vaping is a dangerous behaviour. More smokers will die as a result.