E-cigarette makers say their products are designed to help tobacco smokers quit.

But a new study from Georgia State University raises questions about that claim.

In the study, just published by researchers from GSU’s School of Public Health, vapers had 70 percent lower odds of quitting smoking than nonvapers.

One year into the study, just 9.2 percent of people who both vaped and smoked had quit smoking.

“Absent any meaningful changes, [e-cigarette] use among adult smokers is unlikely to be a sufficient solution to obtaining a meaningful increase in population quit rates,” the authors wrote.

E-cigarettes are better than cigarettes in that they don’t contain tobacco, which has devastating health consequences for lungs. However, they have nicotine — and often in far higher amounts than cigarettes.

Nicotine can be toxic to the heart system; it “literally bores holes through smooth muscle walls and leaves debris in its wake,” according to the Cleveland Clinic, a prominent national medical and research center with particular expertise in heart care. It can also harm early brain development. Experts are demanding more research so that the effects of nicotine in the amounts and context of e-cigarettes can be properly understood.

The GSU study defined quitting as no smoking for 30 days. It noted that the study had limitations, including that it didn’t medically verify the study members had quit, and a limited ability to draw conclusions about what caused the quitting.

Battles are raging over e-cigarettes, which some tobacco companies have pinned their U.S. hopes on now that cigarette smoking has definitively declined here. The e-cigarette maker Juul, in particular, has seen spectacular growth, buoying the U.S. vaping market to $1 billion. Juul’s home­page says it was “founded with the goal of improving the lives of the world’s one billion adult smokers.”

Another study by GSU found that Juul sales had likely been vastly underestimated by traditional national survey methods. The GSU researchers instead went to cashier checkout data and found that traditional data, which rely on asking survey respondents about e-cigarette use, came in far lower than vaping sales data. That study delved into the social media promotion of Juul, and it found that Juul’s success had been pushed on the platforms, which traditional advertising compilations hadn’t necessarily taken into account. Furthermore, those platforms are ones that are heavily used by youths.

E-cigarette sales to youths are illegal. Juul did not respond regarding that study or immediately respond to a request for comment.

GSU is putting a good deal of muscle into e-cigarette research at a moment when its health effects are unknown but use is definitively gaining a foothold. The new study appears in the journal PLOS One.