If the great majority of tobacco smokers who are unable or unwilling to quit would switch without delay to using an alternative source of nicotine
with lower health risks, and eventually stop using it, this would represent a significant contemporary public health achievement. This would only be the case if the recruitment of minors and non-smokers into the nicotine
-dependent population is no higher than it is for smoking, and eventually decreases to zero. Whether ENDS
/ENNDS can do this job is still a subject of debate between those who want their use to be swiftly encouraged and endorsed on the basis of available evidence, and others who urge caution given the existing scientific uncertainties as well as the performance variability of products and the diversity of user behaviour.