Shop products for Medium Chain Triglycerides 
What is it?
Medium-chain triglycerides (MCT) are a class of fatty acids. Their chemical composition is of a shorter length than the long-chain fatty acids present in most other fats and oils, which accounts for their name. They are also different from other fats in that they have a slightly lower calorie content1 and they are more rapidly absorbed and burned as energy, resembling carbohydrate more than fat.2
Where are they found?
Medium chain triglycerides are found in coconut oil, palm kernel oil, and butter. MCT are also available as a supplement.
What do the advocates say?*
Medium chain triglycerides (MCT) are more easily absorbed and burned for energy than other fats, which suggests they might play a role in supplying energy during exercise. Research results have been quite mixed, however, and the large amounts required can lead to gastrointestinal distress, which limits the usefulness of this supplement, even to the few athletes who might benefit.
How much is usually taken by athletes?
MCT contain a class of fatty acids found only in very small amounts in the diet; they are more rapidly absorbed and burned as energy than are other fats.3 For this reason, athletes have been interested in their use, especially during prolonged endurance exercise. However, no effect on carbohydrate sparing or endurance exercise performance has been shown with moderate amounts of MCT (30 to 45 grams over two to three hours).4 5 Controlled trials using very large amounts of MCT (approximately 85 grams over two hours) have resulted in both increased and decreased performance,6 7 while a double-blind trial found that 60 grams per day of MCT for two weeks had no effect on endurance performance.8 A controlled study found increased performance when MCTs were added to a 10% carbohydrate solution,9 but another study found no advantage of adding MCT,10 and a third trial actually reported decreased performance with this combination, probably due to gastrointestinal distress, in athletes using MCTs.11
Are there any side effects or interactions?
Consuming medium chain triglycerides on an empty stomach can lead to gastrointestinal upset. Anyone with cirrhosis or other liver problems should check with a doctor before using MCT. Two reports suggest that MCT may raise serum cholesterol and/or triglycerides.12 13 MCT is actually the preferred fatty acid source for cirrhotic patients, but only when used intermittently.14
At the time of writing, there were no well-known drug interactions with medium chain triglycerides.
*Athletes and fitness advocates may claim benefits for medium chain triglycerides based on their personal or professional experience. These are individual opinions and testimonials that may or may not be supported by controlled clinical studies or published scientific articles on medium chain triglycerides. For more complete and detailed information, including references and safety information, see Medium Chain Triglycerides as nutritional supplements.
References
1. Bach AC, Ingenbleek Y, Frey A. The usefulness of dietary medium-chain triglycerides in body weight control: fact or fancy? J Lipid Res 1996;37:708–26.
2. Bach AC, Babayan VK. Medium-chain triglycerides—an update. Am J Clin Nutr 1982;36:950–62.
3. Jeukendrup AE, Saris WHM, van Diesen RAJ, et al. Exogenous MCT oxidation from carbohydrate-medium chain triglyceride supplements during moderate intensity exercise. Clin Sci 1994;87:33.
4. Berning JR. The role of medium-chain triglycerides in exercise. Int J Sport Nutr 1996;6:121–33 [review].
5. Goedecke JH, Elmer-English R, Dennis SC, et al. Effects of medium-chain triaclyglycerol ingested with carbohydrate on metabolism and exercise performance. Int J Sport Nutr 1999;9:35–47.
6. Van Zyl CG, Lambert EV, Hawley JA, et al. Effects of medium-chain triglyceride ingestion on carbohydrate metabolism and cycling performance. J Appl Physiol 1996;80:2217–25.
7. Jeukendrup AE, Thielen JJ, Wagenmakers AJ, et al. Effect of medium-chain triacylglycerol and carbohydrate ingestion during exercise on substrate utilization and subsequent cycling performance. Am J Clin Nutr 1998;67:397–404.
8. Misell LM, Lagomarcino ND, Schuster V, Kern M. Chronic medium-chain triacylglycerol consumption and endurance performance in trained runners. J Sports Med Phys Fitness 2001;41:210–5.
9. Van Zyl CG, Lambert EV, Hawley JA, et al. Effects of medium-chain triglyceride ingestion on fuel metabolism and cycling performance. J Appl Physiol 1996;80:2217–25.
10. Angus DJ, Hargreaves M, Dancey J, Febbraio MA. Effect of carbohydrate or carbohydrate plus medium-chain triglyceride ingestion on cycling time trial performance. J Appl Physiol 2000;88:113–9.
11. Jeukendrup AE, Thielen JJ, Wagenmakers AJ, et al. Effect of medium-chain triacylglycerol and carbohydrate ingestion during exercise on substrate utilization and subsequent cycling performance. Am J Clin Nutr 1998;67:397–404.
12. Cater NB, Heller HJ, Denke MA. Comparison of the effects of medium-chain triacylglycerols, palm oil, and high oleic acid sunflower oil on plasma triacylglycerol fatty acids and lipid and lipoprotein concentrations in humans. Am J Clin Nutr 1997;65:41–5.
13. Hill JO, Peters JC, Swift LL, et al. Changes in blood lipids during six days of overfeeding with medium or long chain triglycerides. J Lipid Res 1990;31:407–16.
14. Fan ST. Review: nutritional support for patients with cirrhosis. J Gastroenterol Hepatol 1997;12:282–6.
