Quantitative stool fat determination; Fat absorption
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.
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 a normal small intestine.
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.
Reynolds JC, Ward PJ, Rose S, Solomon M. Small bowel. In: Reynolds JC, Ward PJ, Rose S, Solomon M, eds. Netter Collection of Medical Illustrations: Digestive System: Part II - Lower Digestive Tract, The. 2nd ed. Philadelphia, PA: Elsevier; 2017:pg 31-114.
Semrad CE. Approach to the patient with diarrhea and malabsorption. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 140.
Siddiqui UD, Hawes RH. Chronic pancreatitis. In: Chandrasekhara VD, Elmunzer JB, Khashab MA, Muthusamy RV, eds. Clinical Gastrointestinal Endoscopy. 3rd ed. Philadelphia, PA: Elsevier; 2019:chap 59.BACK TO TOP
Review Date: 6/21/2018
Reviewed By: Michael M. Phillips, MD, Clinical Professor of Medicine, The George Washington University School of Medicine, Washington, DC. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2021 A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited.