E-cigarettes are battery-powered gadgets that deliver nicotine through a vapor that may be fruit-or candy-flavored. [Nicolas Tucat/Agence France-presse]

Electronic cigarettes may not help people quit smoking, a new study suggests. But experts say broader research is key, Andrew M. Seaman reports in New York.

A small US study raises new questions about whether using electronic cigarettes will lead people to quit smoking, adding to the debate over how tightly the products should be regulated.

The study, which looked at the habits of 88 smokers who also used e-cigarettes, was published as a research letter in the journal JAMA Internal Medicine on Monday. It found that smokers who also used e-cigarettes were no more likely to quit smoking after a year, compared to smokers who did not use the devices.

Outside experts say the small number of respondents, and a lack of data on whether they intentionally used e-cigarettes to help them quit smoking, mean the findings from the Center for Tobacco Control Research and Education at the University of California, San Francisco can't take the place of much more rigorous study on the subject.

E-cigarettes were first introduced in China in 2004 and have since grown into a $2 billion industry. The battery-powered devices let users inhale nicotine-infused vapors, which don't contain the harmful tar and carbon monoxide in tobacco.

One issue is how strictly US health regulators should control the products. Advocates say e-cigarettes can help smokers quit. Public health experts fear they can serve as a gateway to smoking for the uninitiated, particularly teenagers.

A previous report from the United Kingdom found that people who use e-cigarettes primarily want to replace traditional cigarettes.

"We did not find a relationship between using an e-cigarette and reducing cigarette consumption," says Rachel Grana, the lead researcher on the new study.

Grana and colleagues at the University of California, San Francisco analyzed 2011 survey data collected from 949 smokers. Of those, 88 reported using e-cigarettes.

When the researchers looked at those smokers' responses a year later, they found that the people who reported using e-cigarettes in the 2011 survey were no more likely to quit smoking than the people who did not use e-cigarettes.

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