More smokers use e-cigarettes to help them quit than prescription drugs like Chantix or nicotine gums or patches, a new study finds.

The study of consumer behavior, by the firm Kantar Media, found of adults who said they used a product to help them quit smoking in the last year, 57 percent used e-cigarettes, compared with 39 percent who used a prescription drug such as Chantix, and 39 percent who used over-the-counter products such as nicotine gum or patches.

Kantar Media mailed a questionnaire about health-related behavior to about 50,000 American households, and more than 20,000 people responded, Time reports. The article notes the study did not determine whether e-cigarettes are effective in helping people quit smoking.

Almost 6 million adults in the United States use e-cigarettes, compared with 44 million who use a tobacco or nicotine product, including regular cigarettes, the study found. E-cigarette users are more likely than the national average to be young and male and have lower household incomes.

There is an intense debate among experts about whether e-cigarettes are a useful tool in smoking cessation. A study published in May in the journal Addiction found smokers are 60 percent more likely to be successful in quitting smoking if they switch to e-cigarettes, instead of using nicotine products such as gum or patches.

Last month, a group of leading lung health organizations urged governments to ban or limit the use of e-cigarettes until more is known about the devices’ health effects. The Forum of International Respiratory Societies, which includes more than 70,000 members worldwide, said in a position statement, “Since electronic cigarettes generate less tar and carcinogens than combustible cigarettes, using electronic cigarettes may reduce disease caused by those components. However, the health risks of electronic cigarettes have not been adequately studied. Studies looking at whether electronic cigarettes can aid smoking cessation have had inconsistent results.”