Medium-Chain Triglycerides Overview

Medium-chain triglycerides (MCTs) are fats with an unusual chemical structure that allows the body to digest them easily. Most fats are broken down in the intestine and remade into a special form that can be transported in the blood. But MCTs are absorbed intact and taken to the liver, where they are used directly for energy. In this sense, they are processed very similarly to carbohydrates.

MCTs are different enough from other fats that they can be used as fat substitutes by people (especially those with AIDS) who need calories but are unable to absorb or metabolize normal fats.

MCTs have also shown a bit of promise for improving body composition and enhancing athletic performance.

There is no dietary requirement for MCTs. Coconut oil, palm oil, and butter contain up to 15% MCTs (plus a lot of other fats). You can also buy MCTs as purified supplements.

MCTs can be eaten as salad oil or used in cooking. When taken as an athletic supplement, dosages around 85 mg daily are common.

Fat Malabsorption

A double-blind, placebo-controlled study on 24 men and women with AIDS suggests that MCTs can help improve AIDS-related fat malabsorption. ¹ In this disorder, fat is not digested; it passes unchanged through the intestines, and the body is deprived of calories as well as fat-soluble vitamins.

The study participants were split into two groups: one received a liquid diet containing normal fats, whereas the other group received mostly MCTs. After 12 days, the participants on the MCT formula showed significantly less fat in their stool and better fat absorption than the other group.

Another double-blind study found similar results in 24 men with AIDS-related fat malabsorption. ² The body depends on enzymes from the pancreas to digest fat. In one study, individuals with inadequate pancreatic function due to chronic pancreatitis appeared to be better able to absorb MCTs than ordinary fatty acids. ³ However, this didn't turn out to mean much on a practical basis because, without taking extra digestive enzymes, they could only just barely absorb the MCTs; whereas, if they took digestive enzymes, they absorbed ordinary fats as well as MCTs without difficulty.

1. Craig GB, Darnell BE, Weinsier RL, Saag MS, Epps L, Mullins L, Lapidus WI, Ennis DM, Akrabawi SS, Cornwell PE, Sauberlich HE. Decreased fat and nitrogen losses in patients with AIDS receiving medium-chain-triglyceride-enriched formula vs those receiving long-chain-triglyceride-containing formula. J Am Diet Assoc. 97(6):605-11.
2. Wanke CA, Pleskow D, Degirolami PC, Lambl BB, Merkel K, Akrabawi S. A medium chain triglyceride-based diet in patients with HIV and chronic diarrhea reduces diarrhea and malabsorption: a prospective, controlled trial. Nutrition. 12(11-12):766-71.
3. Caliari S, Benini L, Sembenini C, Gregori B, Carnielli V, Vantini I. Medium-chain triglyceride absorption in patients with pancreatic insufficiency. Scand J Gastroenterol. 31(1):90-4.