Introduction

The European Union (EU) has made substantial progress in tobacco control. Over the past two decades, smoking prevalence declined from 39.4% in 2002 to 24.0% in 2023.1,2 Nevertheless, tobacco use remains a major public health burden, causing over 700,000 premature deaths annually and accounting for about 27% of cancer cases in the region.3,4 The emergence and rapid evolution of alternative tobacco and nicotine-containing products complicate efforts to achieve further reductions in cigarette smoking prevalence. Although manufactured cigarettes retain market dominance, non-cigarette products, such as waterpipes and e-cigarettes, increasingly shape the tobacco and nicotine market.5

The EU and its Member States (MS) have ratified the World Health Organization Framework Convention on Tobacco Control (WHO FCTC) and implemented MPOWER measures to reduce tobacco use, including systematic monitoring of consumption.6,7 In 2021, the EU launched the Europe’s Beating Cancer Plan and set the goal of a ‘Tobacco-Free Generation’ in which <5% of the population uses tobacco.4 Young people are central to this goal, as most people who smoke initiate use between ages 14 and 25, and earlier initiation is associated with greater nicotine dependence and lower likelihood of cessation.8,9

Waterpipe and e-cigarettes share characteristics that make them particularly appealing to young people, including flavours, social acceptability, media influence, and perceived reduced harm.10 These features have contributed to their uptake among adolescents and young adults, including those who have never smoked. Although their historical trajectories differ, waterpipe use expanded globally in the 1990s, whereas e-cigarettes emerged and spread rapidly in the early 2010s,11 both products have become important sources of nicotine experimentation and recreational use among young people, and are therefore epidemiologically comparable in their potential behavioural roles in population-level patterns of experimentation, even if their determinants of uptake and risk profiles may differ.

Despite their shared appeal, waterpipes and e-cigarettes differ in composition and framing. Waterpipes are traditional tobacco products for recreational use, whereas e-cigarettes are more recent devices that typically do not contain tobacco and are sometimes considered within harm reduction or smoking cessation frameworks. However, both products are associated with adverse health outcomes, including cancer, respiratory, and cardiovascular diseases.12 Both expose users to nicotine and contribute to dependence and long-term addiction,13 with growing evidence linking their use to subsequent cigarette smoking initiation.14,15 In this context, our interest is not in equating their toxicological risks, but in examining how two distinct product types are used within population-level patterns of nicotine experimentation and recreational use among youth.

In the EU, both waterpipe and e-cigarette use increased among adults between 2012 and 2014, but diverged thereafter: waterpipe use declined while e-cigarette use continued to rise.16, 17, 18 This divergence may reflect shifts in product appeal, availability, and promotion, raising the possibility that e-cigarettes are increasingly associated with patterns of nicotine use among young people that co-occur with those observed for waterpipes. This raises the hypothesis of a potential “cohort substitution effect”, whereby e-cigarettes may be progressively replacing waterpipes as a preferred vehicle for nicotine experimentation among younger cohorts, even if such transitions are not frequently observed at the individual level. While previous EU-wide analyses reported that young people had higher odds of trying these products compared with older adults,17,18 it remains unclear whether trends among young people mirror those observed in the broader adult population, as existing studies vary methodologically and lack comparability over time.

To address this gap, this study examines trends in waterpipe and e-cigarette use among young people (15–30 years) in the EU between 2012 and 2023, focusing on how the prevalence of each product has evolved over time, and explores differences across sociodemographic groups. By analysing waterpipes and e-cigarettes in parallel, we aim to characterise their joint and divergent population-level patterns of use among young people and to assess whether changes in e-cigarette use co-occur temporally with changes in waterpipe use in this age group.