The U.S. Centers for Disease Control and Prevention (CDC) suggests that smokers who find it difficult to quit smoking could benefit by switching to vaping e-cigarettes.

However, a study, published in the JAMA Network Open, has found that using e-cigarettes did not help smokers to successfully quit cigarettes, according to Science Daily.

Researchers at Herbert Wertheim School of Public Health and Human Longevity Science at the University of California San Diego and UC San Diego Moores Cancer Center conducted the study.

The study’s first author Dr. John Pierce said, “Our findings suggest that individuals who quit smoking and switched to e-cigarettes or other tobacco products actually increased their risk of a relapse back to smoking over the next year by 8.5 percentage points compared to those who quit using all tobacco products.”

“Quitting is the most important thing a smoker can do to improve their health,” he added, “but the evidence indicates that switching to e-cigarettes made it less likely, not more likely, to stay off of cigarettes.”

The researchers looked at more than 13,600 smokers from 2013 to 2015. After a year, 9.4% established smokers had quit, 62.9% remained tobacco-free, while 37.1% had switched to another form of tobacco.

Of the recent smokers who switched to another product, more than 22% used e-cigarettes, with over 17% of switchers using e-cigarettes daily.

Senior author Dr. Karen Messer said, “Our goal in this study was to assess whether recent former smokers who had switched to e-cigarettes or another tobacco product were less likely to relapse to cigarette smoking compared to those who remained tobacco-free.”

After two years of the study, the researcher compared the former smokers who were tobacco-free to those who had switched to e-cigarettes or other tobacco products.

They found that those who switched to any other form of tobacco, including e-cigarettes, were more likely to relapse compared to former smokers who had quit all tobacco, by a total of 8.5 percentage points, according to Science Daily.

Dr. Pierce said, “This is the first study to take a deep look at whether switching to a less harmful nicotine source can be maintained over time without relapsing to cigarette smoking.”

“If switching to e-cigarettes was a viable way to quit cigarette smoking, then those who switched to e-cigarettes should have much lower relapse rates to cigarette smoking,” he added. “We found no evidence of this.”