As for the risks that are mentioned in the letters those views are countered by senior author, Dr. Hayden McRobbie, from the Wolfson Institute of Preventive Medicine at Queen Mary University of London believes "If there are any risks, these will be many times lower than the risks of smoking tobacco." He added: “We need to think carefully about how these products are regulated. What we found is that there is no evidence that these products should be regulated as strictly as tobacco, as or even more strictly than tobacco."