The fat controlled diet is used for to relieve symptoms of diarrhea, steatorrhea, and flatulence or to control nutrient losses caused by the ingestion of excess dietary fat. This diet may be used in the treatment of diseases of the hepatobiliary tract, pancreas, intestinal mucosa, and the lymphatic system as well as the malabsorption syndromes.
The fat intake is restricted as low as 25 grams per day depending on the severity of the condition and doctors recommendation.

Prolonged conditions of steatorrhea or diarrhea may cause nutrient deficiencies of calcium, magnesium, iron, fat-soluble vitamins, folic acid, Vitamin B-12 and B complex vitamins. Vitamin and mineral supplementation may be necessary.