Therapeutic diets are meal plans that control intake of certain foods or nutrients, especially for patients with digestive, kidney, or metabolic issues. Therapeutic diets modify energy, protein, carbohydrate, fat, iron, calcium, salt, vitamins, and fluid intake based on a patient's condition. Examples include high protein diets for liver conditions; low carbohydrate diets for diabetes; low purine diets for gout; high calcium diets for rickets; and sodium restriction for hypertension. The document provides detailed examples of therapeutic diet modifications for various medical conditions.