The aim of this study is to assess the feasibility of beta-hydroxybutyrate (BHB) supplementation in individuals who are undergoing a standard-of-care colonoscopy or flexible sigmoidoscopy.

The aim of this study is to assess the feasibility of β-hydroxybutyrate (BHB) supplementation in individuals who are undergoing a standard-of-care colonoscopy or flexible sigmoidoscopy in order to determine whether BHB supplementation is safe and tolerable. Additionally, this study will determine whether BHB supplementations increases serum BHB levels, and leads to transcription and protein expression changes in the colonic mucosa. BHB supplementation will be performed through oral administration of HVMN Ketone-IQ, a commercially available BHB supplement, with an active ingredient of R-1,3-Butanediol, which gets converted to BHB.

Inclusion Criteria:

• Age of 18 years or older
• Scheduled for a colonoscopy or flexible sigmoidoscopy as part of the patient's standard care
• Can provide informed consent

Exclusion Criteria:

• Subject is pregnant, a prisoner, or is under 18 years of age
• Patient is not able to undergo colonoscopy or flexible sigmoidoscopy
• Prior total proctocolectomy
• History of inflammatory bowel disease
• History of diabetes mellitus and are currently on medical diabetes therapy
• History of chronic kidney disease with an eGFR < 60 mL/min/1.73m2
• Cancer diagnosis where the subject is receiving active therapy
• Use of either a ketogenic diet or intermittent fasting (defined as a fasting period of 16 hours or more per day that is not associated with a medical procedure) during the 4 weeks prior to enrollment