Clear Liquid Diet

A diet of clear liquids maintains vital body fluids, salts, and minerals; and also gives some energy for patients when normal food intake must be interrupted. Clear liquids are easily absorbed by the body. They reduce stimulation of the digestive system, and leave no residue in the intestinal tract. This is why a clear liquid diet is often prescribed in preparation for surgery, and is generally the first diet given by mouth after surgery. Clear liquids are given when a person has been without food by mouth (NPO) for a long time. This diet is also used in preparation for medical tests such as sigmoidoscopy, colonoscopy, or certain x-rays.

Nutrition Facts

A clear liquid diet is not adequate in calories and nutrients. It should not be used for more than five days unless high-protein gelatin or other low-residue supplements are added.

Special Considerations
  1. Limitations
    The physician may limit certain liquids, depending on the patient’s condition, or the surgery or test being performed. Therefore, individual instructions should be strictly followed.
  2. What is a clear liquid?
    A good rule-of-thumb is anything you can see through. For example, apple juice is a clear liquid; milk is not. If unsure, check with the physician or registered dietition.
  3. After surgery and fasting
    Should persistent abdominal cramps or discomfort occur with a clear liquid diet, the patient should notify the physician, nurse, or dietitian at once.
  4. Preparing for a medical test
    It is important that the clear liquid diet be followed exactly. Remember that the value of the examination will depend on getting a thoroughly clean digestive tract.
Food Groups
Group Recommend Avoid
Milk & milk products none all
Vegetables none all
Fruits fruit juices without pulp nectars; all fresh, canned, and frozen fruits
Breads & grains none all
Meat or meat substitutes none all
Fats & oils none all
Sweets & desserts gelatin, fruit ice, popsicle without pulp, clear hard candy all others
Beverages coffee; tea; soft drinks; water; lactose-free, low residue supplements if approved by physiciancoffee; tea; soft drinks; water; lactose-free, low residue supplements if approved by physician all others
Soups bouillon, consommé fat free broth all others
Sample Menu
Breakfast Lunch Dinner
  • strained fruit juice 1 cup
  • gelatin 1 cup
  • hot tea with sugar & lemon
  • consommé 3/4 cup
  • strained fruit juice 1 cup
  • fruit ice 1/2 cup
  • gelatin 1/2 cup
  • hot tea with sugar & lemon
  • consommé 3/4 cup
  • strained fruit juice 1 cup
  • fruit ice 1/2 cup
  • gelatin 1/2 cup
  • hot tea with sugar & lemon
This Sample Diet Provides the Following
Calories 600 Fat virtually none
Protein 6 gm Sodium 1500 mg
Carbohydrates 209 gm Potassium 1440 mg

Author: Frank W. Jackson, M.D.

© Frank W. Jackson, M.D.