Are electronic cigarettes one of the biggest health hazards since tobacco cigarettes — or the best chance to get smokers to quit? Without the research needed to answer that question conclusively, public health officials and regulators are in a fix.

For decades, tobacco companies did everything they could to convince smokers that cigarettes were not killing them — insisting the jury was still out on the science despite dozens of studies that linked smoking with lung disease and cancer. As one tobacco executive famously wrote in 1969, “Doubt is our product…the best means of competing with the ‘body of fact’ that exists in the minds of the general public.”

In the case of e-cigarettes, however, the jury really is still out, with scant scientific studies about whether they are a salvation for hard-core smokers, a potential scourge for young novelty seekers—or something in between.

Which is why, for public health, the sudden explosion of e-cigarettes into mainstream culture has created a quandary. On the one hand, they represent a potential game changer for smoking-cessation efforts — giving new hope to long-time puffers who have tried unsuccessfully for years to quit. On the other, they introduce an untested, potentially dangerous product that could not only spawn a whole new generation of nicotine addicts, but also serve as a gateway to regular cigarettes — just as U.S. smoking rates have hit an all-time low.

Some Harvard T.H. Chan School of Public Health  researchers sense that over the past year, the public health community may be moving toward a tentative agreement on the potential benefits of e-cigarettes. According to Dr. Vaughan Rees, interim director of the School’s Center for Global Tobacco Control and an expert on substance abuse and dependence, the field is coalescing around the idea that, if regulated properly, e-cigs could bolster overall harm reduction by helping smokers quit tobacco cigarettes or helping them smoke less. The trick will be regulation, he adds. “Harm reduction can only work in a regulatory environment that encourages complete switching among current smokers or tobacco users, and discourages use among adolescents.”

Dr. Rees’ suggestion for achieving this net harm reduction may sound counterintuitive and even risky: Make e-cigs more addictive, by raising their nicotine levels. His rationale is that low-nicotine e-cigs are both less likely to deliver the kick that will enable smokers to completely switch and, because of their mild flavor, are more likely to hook young people on nicotine. “We’re eager to find the sweet spot,” says Dr. Rees, “where we support switching away from tobacco cigarettes without unintentionally increasing an individual’s nicotine dependence.” Read more