Vaping may also help individuals give up smoking while considerably lowering their publicity to lethal toxins and bettering their well being outcomes (Lindson et al., 2025; Royal Faculty of Physicians 2024). Nevertheless, with an increase in teen vaping amongst those that have by no means often smoked, persons are questioning whether or not vaping might result in a rise in subsequent teen smoking. This concept is often known as “the gateway speculation”. The speculation originated nearly 100 years in the past and has been famously utilized to hashish use being a “gateway” to different, “tougher”, medication. In a latest umbrella evaluate, Golder et al. (2025) explored the gateway speculation in relation to vaping and subsequent smoking and different dangerous behaviours—right here, we unpack this.
The gateway speculation has been broadly contested, for a lot of causes. The central argument in opposition to the gateway speculation is that we can not actually, ethically, take a look at whether or not youth use of 1 product (e.g., vapes) is related to use of one other (e.g., smoking) amongst younger individuals. To do that, we would want a trial the place younger persons are randomised to vape or not and are then adopted as much as see if they’ve began smoking. That is extremely unlikely to move by any analysis ethics committees.
One of the best obtainable, moral, strategies now we have to check the gateway speculation are inhabitants surveys. Nevertheless, whereas inhabitants surveys may discover that individuals who vape at age 12 usually tend to smoke at age 18, can this ever actually present enough proof of a “gateway” impact? Younger individuals being surveyed may need gone onto smoke anyway, no matter whether or not they used vapes. There are additionally different elements like adjustments available in the market, standard merchandise, or the likelihood that youth are merely getting older or “rising out” of vapes.
The contender to the gateway speculation is the widespread legal responsibility principle. The widespread legal responsibility principle proposes that individuals who vape and smoke have the identical underlying traits, like genetics, optimistic attitudes/tradition in the direction of nicotine use, and being extra prone to take dangers. Certainly, proof within the subject of vaping and smoking means that there are robust genetic vulnerabilities to each behaviours (Khouja et al., 2021), and likewise that the affiliation goes each methods (i.e., vaping being related to subsequent smoking, and smoking being related to subsequent vaping; East et al., 2018). With longitudinal surveys, it’s just about not possible to manage for all of the potential underlying traits (i.e., confounders) of smoking and vaping, so it’s tough to inform whether or not the associations are real or brought on by these confounding elements. A meta-analysis of “gateway” research in 2021 (Chan et al., 2021) addressed this by calculating one thing known as an “E worth”, which permits us to guage the sufficiency of adjustment for confounding. Unsurprisingly, this research discovered a comparatively excessive E-value, indicating that estimates in vaping-smoking “gateway” research should not strong in opposition to unmeasured confounding. General, this proof factors extra in the direction of a standard legal responsibility for each behaviours moderately than vaping being a “gateway” to smoking.
Can vaping actually result in smoking amongst teenagers — or can the ‘gateway’ impact be defined by widespread threat elements?
Strategies
The umbrella evaluate by Golder et al. (2025) synthesises proof of 56 critiques that assessed the associations between youth vaping (publicity) and any bodily or psychological well being harms (final result; together with uptake of smoking or different addictive behaviours). Research assessing quitting smoking as an final result or different optimistic advantages (e.g., lowered stress) have been excluded—that is essential for causes we’ll point out later. The research critically appraised the included critiques utilizing a validated risk-of-bias device, scoring the critiques from critically low to excessive. A youth advisory panel supplied enter on the rising outcomes, implications, and dissemination, which is nice to see and uncommon for systematic critiques.
Outcomes
Most critiques assessed the associations between vaping and smoking uptake (n = 25), though lots of the critiques reported on the identical research. 5 critiques assessed the associations between vaping and subsequent hashish, alcohol, and/or non-prescribed Ritalin/Adderal. Most of those critiques included longitudinal cohort research, thus permitting for evaluation of whether or not vaping is related to subsequent smoking or use of different substances.
The meta-analyses included discovered that odds ratios for the affiliation between vaping and smoking initiation ranged from 1.50 to 26.01, with most research reporting that younger individuals who vape are round 3 times extra seemingly than these not utilizing them to provoke smoking. For different substances, the percentages for associations with vaping ranged from 2.13 to six.67.
The opposite critiques focussed on associations between vaping and respiratory outcomes (e.g., bronchial asthma; 16 critiques), burns/accidents (7 critiques), psychological well being (9 critiques), and cardiovascular problems (4 critiques). These discovered that vaping amongst youth was related to poorer respiratory outcomes (e.g., bronchial asthma, wheezing, bronchitis) and poorer psychological well being. Many of the research included within the critiques, nevertheless, have been cross-sectional which is especially essential for the affiliation between psychological well being and vaping as a result of some research have discovered that youth use nicotine to deal with psychological well being signs, moderately than vaping inflicting poor psychological well being. Some critiques additionally discovered that vaping was related to burns/accidents, though the vast majority of these have been primarily based on case reviews and so may not be generalisable, and plenty of electrical objects could cause burns if used or manufactured inappropriately.
Importantly, the standard of the overwhelming majority of the included critiques have been all rated as critically low attributable to important methodological limitations, together with a scarcity of a-priori strategies, not itemizing excluding research, and insufficient reporting on threat of bias impacts.
Youth who vape seem extra prone to smoke later, however poor research high quality clouds the interpretation of the findings.
Conclusions
The conclusions of the Golder et al. (2025) umbrella evaluate have been that there have been constant associations between vaping and subsequent smoking, marijuana use, alcohol use, bronchial asthma, cough, accidents and psychological well being outcomes. In addition they declare that the “robust associations in potential cohort research are in keeping with a causal relationship between vaping and subsequent smoking”.
The umbrella evaluate indicated constant associations between vaping and subsequent smoking, marijuana use, alcohol use, bronchial asthma, cough, accidents and psychological well being outcomes.
Strengths and limitations
As Golder et al. (2025) establish, key strengths of their evaluate embody being essentially the most complete evaluate of vaping-associated dangers to this point and the inclusion of a public involvement group of younger individuals (which is uncommon with critiques). They thought of an enormous variety of critiques (56 critiques), with most being systematic critiques. Screening was undertaken by two reviewers, enhancing the reliability of the evaluate.
Nevertheless, there are a number of limitations of this work. As Golder et al. (2025) point out, in addition to the outcomes of smoking initiation, a lot of the associations assessed are cross-sectional and, for burns/accidents and cardiovascular outcomes, have been primarily restricted to case reviews, which rank low on the “hierarchy of proof”. In addition they spotlight that high quality of the included critiques was usually low; nevertheless, the authors don’t account for this of their conclusions. Due to this fact, the findings from this evaluate have to be handled with warning.
Extra broadly, the authors don’t have in mind the likelihood that their findings could possibly be defined by a standard legal responsibility. They point out this competing principle of their dialogue however place extra emphasis on the gateway speculation. One of many critiques (Chan et al.) that was included within the umbrella evaluate discovered that estimates in vaping-smoking “gateway” research should not strong in opposition to unmeasured confounding, as talked about earlier on this weblog; nevertheless, the nuance of this research shouldn’t be described by Golder et al. It is a main limitation of the evaluate.
Lastly, we even have the problem of what we’re focussing our consideration on: if researchers are searching for an affiliation between vaping and smoking, that’s what they are going to discover. A latest proof and hole map by Conde et al. (2024) discovered that the overwhelming majority of research assessing vaping and smoking amongst youth give attention to vaping and subsequent associations with smoking, with only a few contemplating whether or not vaping could possibly be a “gateway” away from smoking—that’s, whether or not youth who smoke are utilizing vapes to get themselves off of smoking. It’s well-established that vapes are a lot much less dangerous than smoking and may also help adults to give up smoking. Due to this fact, moderately than repeatedly synthesising proof of poor high quality “gateway” research, researchers could be greatest to focus their efforts on under-researched areas. This might embody analysis into whether or not vaping is a approach out of smoking amongst younger individuals, in addition to particular coverage choices that stability the necessity to stop individuals who have by no means smoked from vaping with guaranteeing they’re obtainable to help adults who smoke to give up.
The evaluate brings collectively a formidable physique of analysis, however poor high quality research and lacking nuance prevents any agency conclusions on the affiliation between vaping and subsequent well being outcomes.
Implications for observe
It essential to keep in mind that vaping is a vital gateway out of smoking for a lot of, and the arguments about youth vaping shouldn’t cloud this focus. Tobacco smoking is the main explanation for preventable dying and incapacity globally, killing as much as two thirds of people that smoke in the long run (World Well being Group, 2025). Vaping is considerably much less dangerous than smoking and there may be high-certainty proof that vaping may also help individuals give up smoking (Lindson et al., 2025; Royal Faculty of Physicians, 2024). NICE scientific tips suggest e-cigarettes to assist individuals give up smoking, encouraging a full swap to cut back the harms from tobacco use. It’s estimated that round 2.7 million individuals in Nice Britain have give up smoking with a vape within the final 5 years (Motion on Smoking and Well being, 2024).
Though the help for the gateway principle of vaping is questionable, we should nonetheless acknowledge that vaping carries dangers and younger individuals and people who have by no means smoked shouldn’t vape (Royal Faculty of Physicians, 2024). It’s subsequently essential that tips and coverage approaches stability the necessity to make sure that vaping doesn’t enchantment to younger individuals with guaranteeing that vapes can be found to adults for the needs of quitting smoking. This might embody insurance policies to make vapes much less interesting to youth and younger adults, akin to standardising packaging and point-of-sale restrictions mixed with initiatives to make them accessible to adults who smoke, akin to Swap to Cease, a authorities scheme that gives free vape kits and help to adults who smoke in England.
Vaping may also help individuals who smoke to give up, however defending younger individuals with out denying adults this device stays a fragile stability.
Assertion of pursuits
The authors of this weblog had no private involvement within the research. KE led the primary research in Nice Britain to evaluate the longitudinal associations between vaping and smoking amongst younger individuals and this research was included in lots of the critiques within the Golder et al. umbrella evaluate. Each KE and ET have labored within the subject of tobacco and nicotine analysis for a few years, finishing their PhDs on vaping and smoking norms (KE) and toxicants from vaping (ET). KE and ET are employed by the Brighton and Sussex Medical College and College Faculty London, respectively. They’ve each co-authored reviews on well being dangers and perceptions of vaping for the Workplace for Well being Enchancment and Disparities (OHID) and Royal Faculty of Physicians.
Hyperlinks
Major paper
Golder S, Hartwell G, Barnett LM, Nash SG, Petticrew M, Glover RE. Vaping and hurt in younger individuals: umbrella evaluate. Tobacco Management. 2025.
Different references
Motion on Smoking and Well being (2024). Almost 3 million individuals in Britain have give up smoking with a vape within the final 5 years.
Chan GC, Stjepanović D, Lim C, Solar T, Shanmuga Anandan A, Connor JP, Gartner C, Corridor WD, Leung J (2021). Gateway or widespread legal responsibility? A scientific evaluate and meta‐evaluation of research of adolescent e‐cigarette use and future smoking initiation. Habit. 116(4):743-56.
Conde M, Tudor Okay, Begh R, Nolan R, Zhu S, Kale D, Jackson S, Livingstone‐Banks J, Lindson N, Notley C, Hastings J (2024). Digital cigarettes and subsequent use of cigarettes in younger individuals: An proof and hole map. Habit. 119(10):1698-708.
East Okay, Hitchman SC, Bakolis I, Williams S, Cheeseman H, Arnott D, McNeill A (2018). The affiliation between smoking and digital cigarette use in a cohort of younger individuals. Journal of Adolescent Well being. 62(5):539-47.
Khouja JN, Wootton RE, Taylor AE, Davey Smith G, Munafò MR (2021). Affiliation of genetic legal responsibility to smoking initiation with e-cigarette use in younger adults: a cohort research. PLoS medication.18(3):e1003555.
Lindson N, Butler AR, McRobbie H, Bullen C, Hajek P, Wu AD, Begh R, Theodoulou A, Notley C, Rigotti NA, Turner T, Livingstone-Banks J, Morris T, Hartmann-Boyce J (2025). Digital cigarettes for smoking cessation. Cochrane Database of Systematic Evaluations, Difficulty 1. Artwork. No.: CD010216. DOI: 10.1002/14651858.CD010216.pub9.
Nationwide Centre for Smoking Cessation and Coaching (2025). Supporting purchasers who need to cease vaping.
Royal Faculty of Physicians (2025). E-cigarettes and hurt discount: An proof evaluate.
World Well being Group (2025). Tobacco Truth Sheet.
