Abstract
While smoking remains a main global cause of preventable morbidity and mortality, a potential inflection point has arrived where it could become possible for non-combustible nicotine products to displace cigarettes and reduce risk for smokers who transition completely from smoking. These have proven consumer satisfaction and are now widely and increasingly available globally. One of the most prominent of these nicotine products are electronic cigarettes (ECs), which are used daily by millions of current and former smokers. The category is not without controversy as these products are not risk free and can cause nicotine dependence. The differing interpretation of science assessing ECs has transpired into inconsistent regulation and product standards, providing an environment for its fragmented manufacturing base which allows for variable product quality and in turn, product quality variability has impacted on how they are viewed. In this review, we assess published scientific evidence to evaluate whether, on balance, ECs fulfil a tobacco harm reduction role by reducing health risks relative to smoking and providing a viable alternative for smokers while having limited appeal to non-smokers.