COffee and Metabolites Modulating the Gut MicrobiomE in Colorectal caNCER

This research study is a chemoprevention clinical trial, designed to test the safety and effectiveness of an investigational intervention to learn whether the intervention works in treating a specific disease. "Investigational" means that the drug is being studied. The investigators plan to recruit 80 participants. * Coffee is a complex mixture of hundreds of bioactive compounds, including caffeine, chlorogenic acids, and other polyphenols. Increasing data suggest the anti-cancer benefit of coffee. Observational data have linked coffee drinking to better survival among patients with colorectal cancer. However, there remains uncertainty surrounding the mode of action. * The U.S. Food and Drug Administration (FDA) has not approved coffee as a treatment for any disease. * The research study procedures include: * Screening for eligibility. * Two study visits * Proton magnetic resonance spectroscopy. * Magnetic resonance imaging * Ultrasound elastography. * Urine, blood, and stool samples collected. * Diet and lifestyle questionnaires * Collection of archival tumor biopsy tissue. * Treatment: Coffee or placebo administered daily, orally for 8-12 weeks.