A clear liquid diet consists of clear liquids — such as water, broth and plain gelatin — that are easily digested and leave no undigested residue in your intestinal tract. Your doctor may prescribe a clear liquid diet before certain medical procedures or if you have certain digestive problems. Because a clear liquid diet can’t provide you with adequate calories and nutrients, it shouldn’t be continued for more than a few days.
Clear liquids and foods may be colored so long as you are able to see through them. Foods can be considered liquid if they partly or completely melt to liquid at room temperature. You can’t eat solid food while on a clear liquid diet.
A clear liquid diet is often used before tests, procedures or surgeries that require no food in your stomach or intestines, such as before colonoscopy. It may also be recommended as a short-term diet if you have certain digestive problems, such as nausea, vomiting or diarrhea, or after certain types of surgery.