Liquid diet

A liquid diet is a diet that mostly consists of liquids, or soft foods that melt at room temperature (such as gelatin and ice cream). A liquid diet usually helps provide sufficient hydration, helps maintain electrolyte balance, and is often prescribed for people when solid food diets are not recommended, such as for people who suffer with gastrointestinal illness or damage, or before or after certain types of medical tests or surgeries involving the mouth or the digestive tract.

A more substantial alternative to liquid diets is the mechanical soft diet, which accepts all types of liquids plus puréed or softened solid foods, such as overcooked pasta, scrambled eggs, bananas and cheesecake. For people who cannot swallow at all, a liquid diet may be delivered to the stomach or intestines through a feeding tube instead. When food cannot be delivered to the digestive tract, e.g., if the digestive tract needs to be empty in preparation for gastrointestinal surgery, then parenteral nutrition (nutrients by intravenous infusion) is the primary choice.

A clear liquid diet, sometimes called a surgical liquid diet because of its perioperative uses, consists of a diet containing exclusively transparent liquid foods that do not contain any solid particulates. This includes vegetable broth, bouillon (excepting any particulate dregs), clear fruit juices such as filtered apple juice, clear fruit ices or popsicles, clear gelatin desserts, and certain carbonated drinks such as ginger-ale and seltzer water. It excludes all drinks containing milk, but may accept tea or coffee.

Typically, this diet contains about 500 calories per day, which is too little food energy for long-term use.

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