E-cigarettes are healthier in some ways than combustable cigarettes but remain a powerful gateway to dangerous addictions, said a pair of Columbia University scientists, including a Nobel Prize winner, on Wednesday.

Their research, published in the New England Journal of Medicine, focuses on the effects of nicotine on the brain. Using the drug is like flicking a neural switch that deepens a person’s susceptibility to addiction. Someone who “vapes” an e-cigarette and then uses cocaine is more likely to develop a cocaine dependency, they say, than someone who has never used nicotine. "While e-cigarettes do eliminate some of the health effects associated with combustible tobacco, they are pure nicotine-delivery devices," said co-author Dr. Denise B. Kandel, a professor of psychiatry at Columbia University Medical Center and researcher at the New York State Psychiatric Institute, in a statement.

Their arguments join a long list of others for and against the widespread use of e-cigarettes, sales of which could reach $1.5 billion this year, according to Bloomberg Industries. Earlier this year, the FDA vowed to push for regulation of the product after the Centers for Disease Control and Prevention reported that calls to poison control centers about e-cigarettes had skyrocketed. More than half of those calls involved children under the age of 5 who had consumed the nicotine.

The consequences of that exposure can be serious, as the new research explains. Kandel and her husband Eric, a neurologist who shared in the 2000 Nobel Prize for research on memory, synthesized their own theories with previous experiments on mice. They demonstrated that when the rodents are exposed to nicotine, it changes their brain chemistry and activates “a reward-related gene” that “primes the animals’ subsequent response to cocaine, providing a molecular basis for nicotine as a gateway drug for cocaine.” In other words, nicotine makes the use of other drugs significantly more risky.

"E-cigarettes have the same physiological effects on the brain and may pose the same risk of addiction to other drugs as regular cigarettes, especially in adolescence during a critical period of brain development,” they wrote. “We don't yet know [experimentally] whether e-cigarettes will prove to be a gateway to the use of conventional cigarettes and illicit drugs, but that's certainly a possibility.” The authors said their research proves one danger of e-cigarettes, indicating future research may find more. "While justifiable on one level,” said Jeffrey Lieberman, a Columbia University psychiatrist, e-cigarettes “may have adverse consequences of which we are not fully aware.”

Source: Kandel DB, Kandel ER. A Molecular Basis for Nicotine as a Gateway Drug. New England Journal of Medicine. 2014.