There are hundreds of thousands of people vaping out there already, so recruiting some subjects wouldnt be a risk, wouldnt be too expensive, and it wouldnt be hard to compare these vapers to smokers

Table 2 Average market share (%) of flavor capsule cigarettes and menthol cigarettes from 2010 to 2020 by WHO region and country income level, Euromonitor Passport (for n countries in each region) Table 3 Market share and average annual growth rate (AAGR) for flavor capsule cigarettes and menthol cigarettes by country (N=78), Euromonitor Passport 20102020 Figure 2 Average percent market share of flavour capsule cigarettes and menthol cigarettes by WHO region and country income level from 2010 to 2020, Euromonitor Passport Market trends of MNCCs by WHO region and country income level In contrast, average market shares for MNCCs remained relatively stable from 2010 to 2020 in WHO regions with the highest market shares: Western Pacific (15.4% to 15.7%), Africa (13.1% to 12.6%), Americas (11.9% to 10.6%), and South-East Asia (10.4% and 10.8%) (Figure 2 and Table 2)

While lifting weights or doing interval training is a great start for improving your metabolism if that is all you do for the entire day you are not going to make serious inroads
Planning a Vape Vending Deployment for an Adult Venue
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