An analysis conducted by UC San Francisco (UCSF) researchers found that rather than aid smoking cessation, e- cigarette users were 28% less likely to quit smoking than smokers of traditional cigarettes only. The study, published in The Lancet Respiratory Medicine, is the largest review to date to assess whether e-cigarettes help people quit smoking.

“The irony is that quitting smoking is one of the main reasons both adults and kids use e-cigarettes, but the overall effect is less, not more, quitting,” said co-author Stanton A. Glantz, PhD, professor of medicine at UCSF.

RELATED: Smoking Cessation Therapies

In 2015, the U.S. Preventive Services Task Force found insufficient evidence to recommend e-cigarettes (also known as vapor pens) as a device to help people quit smoking. As of yet,  the Food and Drug Administration (FDA) has not taken any action against e-cigarette companies who claim they are effective for quitting smoking.

The UCSF researchers reviewed 38 studies to examine the correlation between e-cigarette use and smoking cessation. They combined the results from this review with a meta-analysis of 20 studies which included control groups of smokers not using e-cigarettes. Data from this analysis revealed that those who used e-cigarettes were 28% less likely to quit than those who did not.

“The fact that they are freely available consumer products could be important,” said Dr. Glantz. The authors wrote, “The inclusion of e-cigarettes in smoke-free laws and voluntary smoke-free policies could help decrease use of e-cigarettes as a cigarette substitute, and, perhaps, increase their effectiveness for smoking cessation.”

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