High schoolers all over the world have watched as peers are affected by the rise of electronic cigarette usage, with youth e-cigarette use rising 1,800% just between 2011 and 2019 (Truth Initiative, 2019). E-cigarettes have become an increasingly prevalent health risk as research shows growing numbers of youth addicted to the e-cigarettes’ active ingredients—a combination of nicotine and vitamin E acetate. The human gut microbiome is the collection of the hundreds of species of bacteria living in the gut which have been connected to diseases from type 2 diabetes to heart disease. The purpose of this project is to examine whether these e-cigarette ingredients shift the growth of several key species in the gut microbiome, Staphylococcus epidermidis, Escherichia coli, and Enterobacter aerogenes. Gastric and intestinal in vitro digestion procedures were performed, the gastric phase using porcine pepsin enzyme and the pH of the intestinal phase afterward using pancreatin amylase enzyme. Spectrophotometer data collection allowed bacteria to culture in water bath shaker while being exposed to nicotine, vitamin E acetate, water control, and nicotine+vitamin E acetate for a total of 4 data points each trial, each collected an hour apart. 6 trials per treatment were performed. Results showed that combined exposure of nicotine and vitamin E acetate significantly decreased growth of Firmucuite S.epidermidis but significantly increased growth of Proteobacteria E.aerogenes and E.coli. The affected growth of Firmicutes and Proteobacteria in this study, two of the largest groups of gut bacteria, show potential for detrimental gut dysbiosis due to e-cigarette consumption. Future studies will address the presence of thousands of other important gut bacterial strains of various phyla and test variables such as exposure time and concentrations