Study to Assess Colonic Microbiota Changes in Response to Energy Drink Consumption

Inclusion Criteria: * Adults ≥ 18 years of age AND ≤ 40 years of age * Written informed consent obtained from the subject and the subject agrees to comply with all the study-related procedures * Subject willing to complete/comply with study required specimen and survey assessments * Current energy drink consumption of ≤2 energy drinks weekly * Written informed consent obtained from the subject to participate in two companion biobanks: 1) Dr. Thomas George's Tumor and Biospecimen Sample Biobank and 2) Dr. Ryan Thomas's Microbiorepository for future research. Exclusion Criteria: * Personal history of colorectal cancer (CRC) * Inflammatory Bowel Disease (IBD) * Chronic diarrhea or other chronic gastrointestinal (GI) problems felt to interfere with study conduct per the PI * Regular (daily) intake of probiotics * Oral or IV antibiotic use within the past 28 days (prior to intervention start date) * Known intolerance of or sensitivity to caffeine * Prisoners or subjects who are involuntarily incarcerated, or subjects who are compulsorily detained for treatment of either a psychiatric or physical illness. * Known pregnancy at the time of enrollment