Here is a warning you will never see on a pack of cigarettes: "The Surgeon General Has Determined That Cigarette Smoking May Enhance Your Enjoyment of Cocaine." Even for people who consider enhanced enjoyment of cocaine a drawback rather than an advantage, that risk probably would pale beside cancer, heart disease, and emphysema. But if you wanted to scare people away from a nicotine delivery product that poses none of those hazards, you might resort to warning them that it could prime their brains for cocaine pleasure. And that is exactly what Columbia neuropsychiatrist Eric Kandel and his wife, Columbia epidemiologist Denise Kandel, do in an article published by the New England Journal of Medicine this week.

The article is mostly devoted to a description of experiments in which the Kandels dosed mice with nicotine and cocaine. They found that the former enhanced the effects of the latter, as measured by activity levels, conditioned place preference, and various brain responses. The Kandels view these results as evidence to support their theory that "gateway drugs" such as tobacco, alcohol, and marijuana physiologically prime people to enjoy other psychoactive substances. They also think their mouse research is a reason to be wary of electronic cigarettes:

Although e-cigarettes eliminate some of the morbidity associated with combustible tobacco, they and related products are pure nicotine-delivery devices. They have the same effects on the brain as those reported here for nicotine…and they pose the same risk of addiction to other drugs and experiences….Whether e-cigarettes will prove to be a gateway to the use of combustible cigarettes and illicit drugs is uncertain, but it is clearly a possibility.

Clearly a possibility! More than enough for a new drug panic. "E-Cigarettes Are Gateway to Substance Abuse and Addiction," Time declared. "New study suggests e-cigarettes are a 'gateway drug,'" said The Week. The New York Daily News warned that "e-cigarettes could be a gateway to hard drugs." According to Forbes.com health writer Melanie Haiken, the Kandels' research "shows" that "e-cigarettes may be a 'gateway' drug for teenagers."

Keep in mind that the Kandels' research pertains to nicotine in general, not e-cigarettes specifically. So whatever the risk that nicotine will lead to cocaine, it applies equally to conventional cigarettes (as well as FDA-approved nicotine replacement products) and therefore does not count as an argument against switching from smoking to vaping, which dramatically reduces health hazards by eliminating tobacco and combustion (as even the Kandels begrudgingly acknowledge).

But what about the children? The Kandels mention the possibility that teenagers who otherwise would never smoke tobacco might decide to do so after trying e-cigarettes, even though the research they are discussing has nothing to do with that issue. Here is how a recent review in the journal Addiction summarized the empirical basis for the fear that vaping will lead to smoking:

Although there have been claims that EC [electronic cigarettes] is acting as a "gateway" to smoking in young people, the evidence does not support this assertion. Regular use of EC by non-smokers is rare and no migration from EC to smoking has been documented (let alone whether this occurred in individuals not predisposed to smoking in the first place). The advent of EC has been accompanied by a decrease rather than increase in smoking uptake by children.

There is even less evidence that vaping is boosting cocaine consumption, which has been declining since e-cigarettes were introduced. Furthermore, notes Carl Phillips of the Consumer Advocates for Smoke-Free Alternatives Association (CASAA), "cocaine use peaked long after smoking rates had come down, exactly the opposite of what [the Kandels] predict."

In leaping from mouse to man, the Kandels make reckless assumptions about psychology and the nature of addiction. It is not at all clear that the data they gathered from rodents in their laboratory are relevant to humans living in the real world. "This study tells us little about human biology and nothing at all about real-world human behavior," says Phillips. "It does not even measure mouse behavior. The study provides no evidence there is a gateway effect, and there is no reason to believe there is one." CASAA President Julie Woessner calls it "a classic case of someone with a political agenda tacking their opinions onto technical research and trying trick the press into reporting it that way." Fortunately for the Kandels, the press is easy to trick.