What can you eat the day before a colonoscopy?

The day before a colonoscopy, MD Anderson Cancer Center recommends eating a clear liquid diet. Patients are to avoid eating solid foods, but the diet allows them to have gelatin and broth.

The purpose of the clear liquid diet is to maintain hydration and electrolytes during the time that a normal diet is not allowable, according to Mayo Clinic. Doctors sometimes ask colonoscopy patients to avoid juices, sodas or gelatins that contain red coloring the day before their procedure. The clear liquid diet does not provide enough calories to sustain the body over a long period, and the patient is to return to a normal diet as soon as his doctor allows.