Researchers from the University of Technology Sydney, University of Vermont and the Woolcock Institute of Medical Research conducted an animal study in mice to determine the effect of flavored e-cigarettes, with or without nicotine, on allergic airways disease. Results of the study showed that some flavored e-cigarettes may alter asthma pathophysiology even when used without nicotine.
In this study the flavour Black Licorice exaggerated airway inflammation whereas Cinnacide had the opposite effect, suppressing airway inflammation. Additionally, Cinnacide increased airway sensitivity and Banana Pudding flavour exaggerated the level of tissue scarring. All e-cigarette liquids containing nicotine suppressed airway inflammation, consistent with the known anti-inflammatory properties of nicotine.
Results of the study are published in Nature Scientific Reports.