Vaping, a gateway to youth smoking and a factor in increased health risks

A large-scale study published in the journal Tobacco Control[1] highlights the health and behavioral risks associated with vaping among young people. This analysis, which compiles 56 systematic reviews, establishes a consistent link between e-cigarette use and subsequent initiation of smoking. It also highlights associations with alcohol and cannabis use, respiratory disorders, and mental health problems. These findings reinforce calls for stronger regulations governing access to and promotion of these products among adolescents and young adults.

The work was coordinated by the University of York and the London School of Hygiene & Tropical Medicine. It is the largest review of journals devoted to youth vaping, bringing together data from 384 publications, of which 56 met the criteria.[2]The authors included studies focused on people under 25 and published after 2015 to reflect the evolution of vaping devices, including the rise of disposable models.

International medical databases such as Medline, Embase, PsycInfo, and KSR Evidence were searched. Publications were independently assessed by multiple researchers and cross-validated. Where possible, quantitative analyses were conducted to aggregate results and produce robust overall estimates. A youth advisory panel from the Association for Young People's Health also contributed by providing insight into the reception and implications of the findings within their generation.

A gateway effect between vaping and smoking confirmed

One of the most consistent and concerning findings of this review is the link between e-cigarette use and smoking initiation among youth. Results from 21 systematic reviews indicate that adolescents and young adults who have ever vaped are on average three times more likely to subsequently try a traditional cigarette than those who have never vaped. This trend was observed in several countries, with statistical estimates varying but all converging on a significantly increased risk. Longitudinal analyses, which track behaviors over several months or years, confirm the robustness of this association.

Several hypotheses exist to explain this phenomenon. The first is the gateway effect, according to which familiarity with gestures, inhalation, and nicotine addiction encourages the transition to combustible cigarettes. A second hypothesis, known as "common predisposition," suggests that young people who start vaping already have vulnerable traits or a social environment that makes them more inclined to experiment with different psychoactive products, including tobacco. A third, more minority, explanation suggests that vaping could turn some young people away from cigarettes by offering them an alternative perceived as less harmful.

However, the body of data gathered in this review argues against this last hypothesis. In almost all cohorts studied, young vapers are not only more likely to initiate smoking, but they also tend to smoke earlier, more often, and in greater quantities. In other words, far from reducing tobacco experimentation, vaping appears to increase its likelihood and intensity.

These results are all the more worrying because they concern a particularly vulnerable age group, according to the authors. Adolescence and early adulthood are periods of high sensitivity to nicotine addiction. Exposure to nicotine through vaping can thus create a favorable environment for the rapid onset of regular tobacco use. This mechanism contributes to the idea that vaping, particularly when initiated at an early age, constitutes a major risk factor for the onset of smoking and for the perpetuation of the tobacco epidemic.

A close link with alcohol and cannabis consumption

The analysis highlights a strong association between e-cigarette use and subsequent use of other psychoactive substances among young people, particularly alcohol and cannabis. Five systematic reviews, totaling 91 primary studies conducted in various international settings[3], converge towards the same observation: vaping is accompanied by a significantly higher probability of experimentation and regular use of these substances.

Regarding cannabis, the results show that young vapers have a 2.7- to 6-fold increased risk of using this substance. For alcohol, the magnitude of the associations is even higher. Three systematic reviews indicate that young vapers have a 4.5- to 6.7-fold increased risk of consuming alcohol compared to those who have never used an e-cigarette. These associations appear stronger among adolescents than among young adults, highlighting the decisive influence of vaping on poly-drug use trajectories at an early age.

E-cigarettes, often perceived as less dangerous or more socially acceptable than traditional cigarettes, can play a role in normalizing use and lowering psychological barriers to other substances, the authors indicate. Vaping devices themselves, particularly rechargeable models, are sometimes used as vehicles for cannabis or other drug use, which helps reinforce the link between these uses.

These data demonstrate that vaping cannot be considered in isolation. It contributes to an environment where young people combine several consumption behaviors that can lead to increased health, psychological, and social risks. Far from being a neutral or protective tool for young people, the use of e-cigarettes appears to amplify vulnerabilities linked to alcohol and cannabis, two substances already widely consumed during adolescence and responsible for major health and social consequences.

Respiratory and other health effects of concern

One of the most well-documented sets of findings concerns respiratory damage associated with vaping. Eight systematic reviews have found a significant increase in the risk of asthma in young people. The data indicate a 20- to 36-fold increase in the likelihood of receiving an asthma diagnosis, and a 44-fold increase in the risk of an exacerbation in those already with asthma. These findings are based on 47 primary studies, including several large cohorts, and confirm the consistency of the associations observed across different national settings.

In addition to asthma, other respiratory disorders appear more common among young vapers. Cross-sectional studies have shown an increased prevalence of chronic cough, with risks multiplied by 1.3 to 2.1 depending on the intensity of use. Cases of bronchitis and pneumonia have also been reported, as have episodes of wheezing and dyspnea. Field data suggest that exposure to e-cigarette aerosols can cause inflammatory reactions and acute respiratory irritation.

The effects of vaping are not limited to the respiratory system. The review highlights a range of emerging conditions that, although less studied, are attracting increasing attention. Studies on oral health indicate that young vapers more frequently report gum pain, bleeding, dry mouth, and oral mucosal lesions. An association with an increased risk of caries is also suggested, although data remain limited.

Other effects concern the neurological sphere. Several cross-sectional studies report an increased frequency of headaches, migraines, and dizziness in young people using e-cigarettes compared to those who do not. These symptoms, often considered benign, could reflect acute effects of nicotine and inhaled solvents on the nervous system.

Fertility is also among the areas where concerning signals are emerging. A study of young men in Denmark shows that daily e-cigarette use is associated with a decrease in total sperm count. While the data remains limited, they highlight a long-term risk to reproductive health.

Concerning mental health problems

Beyond the physical consequences, the review highlights a set of concerning links between vaping and the mental health of young people. Seven systematic reviews examined these associations, drawing on more than sixty studies conducted primarily in North America, Europe, and East Asia. The results, although often derived from cross-sectional surveys, converge to show a worsening of various psychological disorders among adolescents and young adults who use e-cigarettes.

The strongest evidence relates to depression and anxiety disorders. Young vapers are at increased risk of experiencing depressive symptoms compared to those who do not use e-cigarettes. Several analyses highlight a higher prevalence of mood disorders among regular users, suggesting a possible link between nicotine exposure and disruption of the neurobiological mechanisms that regulate mood and motivation.

Other psychological effects have also been reported. E-cigarette use appears to be associated with a higher incidence of attention deficit disorder and hyperactivity. Available studies also show that vaping is linked to a deterioration in sleep quality: adolescents who vape report shorter sleep duration, particularly on weekends, and a higher proportion of fatigue and daytime sleepiness. These disturbances, if they persist over time, can have significant consequences on the psychological well-being, physical health, academic success, and social integration of young people.

Implications for public policy

The results of this review confirm the need for increased government action to regulate vaping, according to the authors. The magnitude and consistency of the associations highlighted—whether it be an increased risk of switching to tobacco, alcohol and cannabis consumption, respiratory problems, or even impacts on mental health—show that e-cigarettes cannot be considered a harmless product in this particularly vulnerable age group.

Several areas for intervention emerge. The first concerns restricting young people's access to e-cigarettes. This involves stricter control of sales, including online, as well as appropriate sanctions to limit regulatory circumvention practices. Indeed, the data suggest that ease of access remains a key factor in the phenomenon's expansion. The second area concerns advertising and marketing. Vaping devices are often presented in an attractive manner, with fruity or sweet flavors and colorful designs that particularly appeal to adolescents. The review's findings support the idea that these marketing strategies contribute to the initiation and widespread adoption of vaping. Limiting, or even banning, flavors designed to specifically attract young people, as well as strictly regulating promotional practices, appears to be a necessary public health measure.

A third lever lies in product taxation and pricing, which are proven instruments for reducing tobacco consumption and could be applied to vaping. The introduction of specific taxes on vaping devices and liquids could help reduce their attractiveness, particularly among younger people, who are sensitive to the price factor.

Finally, these results call for increased monitoring and research. The rapid evolution of vaping devices and usage practices requires constant scientific and regulatory monitoring. New studies, particularly longitudinal ones, should be encouraged to better understand the long-term effects, particularly on mental health, fertility, and neurodevelopment.

Internationally, the review's findings echo calls from the World Health Organization, which describes the rise of vaping among young people as "alarming." It urges governments to integrate e-cigarettes into their overall strategies to combat tobacco and nicotine products, ensuring that vaping devices do not become a gateway to other addictions.

Solid results despite certain methodological limitations

The authors nevertheless note some methodological limitations. The majority of the included reviews were assessed as of variable quality according to the AMSTAR 2 tool, which mainly reflects frequent gaps in reporting (e.g., the absence of a detailed list of excluded studies) rather than a systematic weakness of the results. Most of the data come from observational studies, which does not allow a formal establishment of a causal relationship, but the consistency and coherence of the observed associations reinforce their credibility. This is particularly true for mental health: while the majority of the work is based on observational studies that do not allow a direct causal link to be established, the convergence of results, their consistency across different geographical contexts, and the existence of plausible biological mechanisms—including the effects of nicotine on the central nervous system during the developmental period—support the idea that vaping constitutes an additional risk factor for young people. The authors also highlight an overlap between certain primary studies, as well as heterogeneity linked to the diversity of contexts, devices and indicators analyzed. Finally, certain areas remain little explored, such as fertility, oral health or neurodevelopment, which justifies continued research. These limitations do not invalidate the results, but invite them to be interpreted as a state of knowledge to date, which will benefit from being consolidated by new large-scale longitudinal studies.

©Generation Without Tobacco

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[1] Golder S, Hartwell G, Barnett LM, et al Vaping and harm in young people: umbrella review Tobacco Control Published Online First: 19 August 2025. doi: 10.1136/tc-2024-059219

[2] Only studies involving children, adolescents, and young adults under 25 years of age were included, with the possibility of including separate analyses for this age group when the reviews concerned larger populations. Only systematic reviews and umbrella reviews were considered, excluding scoping reviews, editorials, or primary studies. The exposure studied concerned exclusively the use of e-cigarettes, with or without nicotine, and the outcomes had to concern harmful effects (physical or mental health, smoking initiation, use of other substances), excluding potential benefits such as smoking cessation. Reviews published before 2015 or not available in English (or without translation) were excluded.

[3] The authors point out that the 91 primary studies included in these five systematic reviews were conducted in a wide range of countries, going beyond the Anglo-Saxon context alone: United States, United Kingdom, Australia, Sweden, Hong Kong, Poland, Russia, Iceland, Canada, Switzerland, China, Greece, France, Mexico, South Korea, Taiwan and Germany.