The fecal fat test measures the amount of fat in the stool. This can help gauge the percentage of dietary fat that the body does not absorb.
Quantitative stool fat determination; Fat absorption
There are many ways to collect the samples.
Collect all stool that is released over a 24-hour period (or sometimes 3 days) in the containers provided. Label the containers with name, time, and date, and send them to the lab.
Eat a normal diet containing about 100 grams (g) of fat per day for 3 days before starting the test. The health care provider may ask you to stop using drugs or food additives that could affect the test.
The test involves only normal bowel movements. There is no discomfort.
This test evaluates fat absorption to tell how well the liver, gallbladder, pancreas, and intestines are working.
Fat malabsorption can cause a change in your stools called steatorrhea. To absorb fat normally, the body needs bile from the gallbladder (or liver if the gallbladder has been removed), enzymes from the pancreas, and normal intestines.
Less than 7 g of fat per 24 hours.
Decreased fat absorption may be caused by:
There are no risks.
Factors that interfere with the test are:
Hogenauer C, Hammer HF. Maldigestion and malabsorption. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger & Fordtran's Gastrointestinal and Liver Disease. 10th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 104.
Semrad CE. Approach to the patient with diarrhea and malabsorption. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 140.