A report published Monday in JAMA Internal Medicine shows that smokers who use e-cigarettes are no more likely to quit smoking after a year than smokers who did not use them. A total of 88 participants were included in the study organized by the Center for Tobacco Control Research and Education at the University of California, San Francisco. The data is sure to add fodder to the debate over how closely regulated e-cigarettes should be. Proponents claim that e-cigarettes can help smokers quit, but public-health advocates worry that they will end up being used by nonsmokers, especially teenagers. First introduced in China in 2004, e-cigarettes have become a $2 billion industry.