Harsh and sweet sensations predict acute liking of electronic cigarettes, but flavor does not affect acute nicotine intake: a pilot laboratory study in men.

INTRODUCTION Electronic cigarette (eCig) use is increasing in popularity, and thousands of flavors are available. Adolescent vaping rates in the United States have nearly doubled in the past year. Unlike combustible tobacco, added flavors are not currently regulated for electronic cigarette products. Here, we investigated the role of flavor in eCig liking and acute intake. METHODS Men (n=39) aged 18-45 vaped in a controlled laboratory setting after being randomized to one of four e-liquids: 6mg nicotine/ml Cherry, 18mg/ml Cherry, 6mg/ml Chocolate, or 18mg/ml Chocolate. They completed several questionnaires, and vaped ad libitum for 10 minutes. After the first puff, participants rated sensations (sweetness, bitterness, coolness, harshness/irritation) on general labeled magnitude scales (gLMS) and rated overall liking on a generalized hedonic scale. Once the 10-minute session ended, participants made another set of ratings. RESULTS Liking was generally stable across the vaping session and liking varied substantially across the 4 conditions. Across all conditions, sensory ratings predicted liking: harshness/irritation was negatively associated with first puff liking while perceived sweetness was positively associated with first puff liking. First puff liking associated with increased amount of e-liquid vaped, but not total nicotine intake. Participants appeared to titrate their nicotine intake regardless of assigned condition. CONCLUSION Flavored eLiquids affect acute rated liking, but not acute nicotine intake. IMPLICATIONS These data suggest individuals who regularly vape may titrate their nicotine intake, regardless of flavor, and contrary to expectations, acute liking did not predict total intake. However, more-liked flavors may potentially make higher nicotine levels more tolerable by adding pleasant sensations directly, rather than by perceptual masking that reduce aversive sensations.