Hua, My, Mina Alfi, and Prue Talbot. "Health-related effects reported by electronic cigarette users in online forums." Journal of medical Internet research 15.4 (2013): e59.

This study analyzes health effects associated with e-cigarette use by examining original posts from three online forums. A total of 405 symptoms were reported, with 78 classified as positive and 326 as negative. The most frequently affected areas included the mouth, throat, and respiratory, neurological, sensory, and digestive systems. The findings highlight the complex nature of health effects experienced by users, revealing both single and interacting symptoms across different organ systems.