Raising the minimum vaping age may inadvertently increase the risk of teen smoking by making it harder for adolescents to quit traditional tobacco products, a new study suggests.

The latest findings, revealed days before California makes its decision on whether it should jump on the bandwagon of raising the minimum age for purchasing electronic nicotine devices, suggest that lawmakers should think again before establishing policies that lump electronic cigarettes and regular cigarettes together. Forty-seven states have already established age restrictions on purchasing electronic cigarettes.

Researchers believe that setting the same legal purchasing age for electronic nicotine devices, which include vape pens, hookah pens and electronic cigarettes, will result in higher teen smoking rates.

"We should regulate tobacco products proportionate to their risks, and e-cigarette evidence suggests they're less risky products," researcher Michael Pesko, a health economist and assistant professor of healthcare policy at Weill Cornell Medicine, said in a university release. "While there's some risk, it would be a mistake to regulate them the same way we regulate cigarettes."

Previous studies suggested that electronic nicotine devices have become more popular among teens than traditional cigarettes, with 13.4 percent using electronic cigarettes compared to 9.2 percent using traditional cigarettes.

After analyzing tobacco data from 2007 to 2013, researchers linked state-imposed electronic cigarette age purchasing constraints to an overwhelming 11.7 percent increase in teen tobacco use. Researchers said that the latest findings suggest teens are substituting traditional tobacco products with electronic nicotine devices.

"For cigarette use, we separate our results into cigarette use frequency. We found causal evidence that electronic nicotine delivery systems age purchasing restrictions increased adolescent regular cigarette use by 0.8 percentage points. electronic nicotine delivery systems age purchasing restrictions were not associated with cigar use, smokeless tobacco use, or marijuana use," researchers wrote in the study. "We document a concerning trend of cigarette smoking among adolescents increasing when electronic nicotine delivery systems become more difficult to purchase."

"One practical implication is that recently both New York City and Hawaii changed their legal purchasing age for both cigarettes and e-cigarettes to 21," Pesko concluded. "Without commenting on the merits of raising the cigarette minimum purchasing age to 21, results from this study suggest it would have been better from a public health standpoint to increase the purchasing age to 21 only for cigarettes, and not e-cigarettes."

The findings were recently published in the journal Preventive Medicine.