While cigarette smoking has declined in the US, vaping has increased dramatically—especially among younger Americans. While vaping may be less harmful to human health than combustible tobacco products like cigarettes, it still contains highly addictive nicotine and other potentially harmful but not well-understood chemicals. And yet many of us don’t really know exactly what vaping is and how it differs from cigarette smoking. Should vaping be seen as a less harmful alternative to cigarettes for smokers, or a gateway to nicotine and other addictions for teens and current non-smokers? How is vaping regulated and does this need to change? In the sixth episode of Epidemiology Counts, Bryan James and Matt Fox interview Dr. Craig Ross from the Boston University School of Public Health about the health effects and increasing rates of vaping, and whether this can be seen as a net benefit or harm to society.