Time-restricted Eating Versus Daily Continuous Calorie Restriction on Body Weight and Colorectal Cancer Risk Markers

Eligibility Criteria

• 1. 45-70 years old,
• 2. BMI 30-49.99 kg/m2
• 3. Are up to date with CRC screening.
• 1. Have a history of renal disease, autoimmune disorders, immunodeficiency, malabsorptive disorder, significant gastrointestinal and hepatic disease, surgical change in gastrointestinal anatomy, severe ischemic heart disease, severe pulmonary disease, severe mental health disorder, eating disorder, or bariatric surgery;
• 2. Abuse alcohol (\> 50 grams/day), illicit drugs (other than self-reported marijuana use), or use combustible tobacco;
• 3. Have controlled type 2 diabetes or undiagnosed uncontrolled diabetes based on hemoglobin A1c (HbA1c) \> 9.0%;
• 4. Have a history of cancer treatment within the past 12 months, CRC, genetic predisposition to CRC (e.g., Lynch syndrome);
• 5. Have a baseline body weight \> 450 lbs (weight limitation of the DXA);
• 6. Are on a weight loss diet or actively involved in a formal weight loss program (e.g., Weight Watchers);
• 7. Are not weight stable for 3 months prior to the study (weight gain or loss \> 4 kg);
• 8. Are unable to keep a food diary for 7 consecutive days during screening;
• 9. Are night shift workers;
• 10. Are pregnant or trying to get pregnant;
• 11. Are taking drugs that influence study outcomes (weight loss medications);
• 12. Are non-English speaking
• 13. Are taking anticoagulant medications or medications with endoscopic risk
• 14. Are taking antivirals or immunosuppressant medications
• 15. Don't have regular access to an email address and computer/smartphone/tablet
• 16. Are currently following a diet that requires fasting on a weekly basis
• 17. Currently eat for less than 10 hours of the day (determined by asking participants what time they start and stop eating on a usual day)