Researchers reviewed nearly 700 e-cigarette studies. What did they find?

E-cigarettes have altered the market for tobacco products in recent years, leaving many lingering questions: How harmful are they compared to cigarettes? Can they help smokers quit? Is vaping on the rise?

Researchers from Truth Initiative® reviewed 686 peer-reviewed studies to assess the most up-to-date science because, as they write in their paper in American Journal of Preventive Medicine, there is an urgent need to identify “how to strike a balance between potential benefits and harms to public health.”

“Now that the Food and Drug Administration has the power to regulate e-cigarettes, it is critical that public health advocates understand the latest peer-reviewed research,” said Allison Glasser, senior project manager for Tobacco Science and Research at Truth Initiative’s Schroeder Institute® and the study’s lead author. “Because the tobacco marketplace is changing so dramatically, we must continually evaluate the science.”

After reviewing nearly 700 studies published between 2010 and May 2016, the researchers reported several major findings.

E-cigarettes pose substantially less harm than traditional cigarettes

Although it is difficult to pinpoint a precise magnitude of difference, researchers found that e-cigarettes pose significantly less harm to smokers than traditional cigarettes. Overall, e-cigarettes expose users to fewer toxins than cigarettes, and cigarette smokers who switched to e-cigarettes had reduced blood pressure and improved lung function.

The researchers stress that more long-term studies are needed, however, to assess the impact of these products on the public as a whole and to determine their long-term health effects.

Use is increasing overall

Studies show that e-cigarette use is increasing, particularly among current smokers, and a majority of them report using the products to help quit smoking. Vaping experimentation surged since being introduced in the U.S., but 2015 data shows a leveling off.

E-cigarettes can be effective quit tools

The strongest cessation studies determined that e-cigarettes helped some smokers quit or cut down on cigarettes, with some studies finding that they can be at least as effective as nicotine replacement therapy.

Products vary, and more research is needed

The technologies, flavors, ingredient combinations and nicotine concentrations vary across e-cigarettes and the products continue to evolve. That poses a problem for research, and the investigators note that a method is needed to characterize products by nicotine and toxicant levels. Researchers should also consider the product type’s potential harms compared to both smoking cigarettes and not using any products. Also needed: consistent definitions for types of users and patterns of use, which will strengthen future research.

“Only by understanding the total impact of these products—including patterns of use and long-term health effects—can we design policies that strike the appropriate balance between potential benefits and harms to public health,” Glasser said.