The report issued Tuesday wrestles with the potential benefits and harms of the vapor-emitting devices. But those effects may not be known for decades because of how slowly illnesses caused by smoking emerge.
The report from the National Academies of Sciences, Engineering and Medicine analyzed more than 800 studies of e-cigarettes but underscores the lingering questions about the devices. It remains unclear if they help smokers quit cigarettes.
The Food and Drug Administration gained authority to regulate e-cigarettes in 2016, but has delayed several key regulations on the industry.