MCTs passively diffuse from the GI tract to the portal system (longer fatty acids are absorbed into the lymphatic system) without requirement for modification like long-chain fatty acids or very-long-chain fatty acids. In addition, MCTs do not require bile salts for digestion. Patients that have malnutrition or malabsorption syndromes are treated with MCTs because they do not require energy for absorption, utilization, or storage.
The fatty acids found in MCTs are called medium-chain fatty acids. The names of the medium-chain fatty acids (and the corresponding number of carbons) found in MCTs are caproic acid (C6), caprylic acid (C8), capric acid (C10), and lauric acid (C12). Like all triglycerides (fats and oils), MCTs are composed of a glycerol backbone and three fatty acids, hence the name triglyceride; in the case of MCTs, 2 or 3 of the fatty acid chains attached to glycerol are medium chain in length. The approximate ratios of these fatty acids in commercial MCT products derived from coconut oil are 2(C6):55(C8):42(C10):1(C12).
Dietary relevance 
The milk fats of humans and guinea pigs are largely made up of long-chain fatty acids. The milk fats of cows, sheep, and goats are rich in short-chain fatty acids. The milk fats of horses contain large amounts of medium-chain fatty acids.
Some studies have shown that MCTs can help in the process of excess calorie burning, and thus weight loss. MCTs are also seen as promoting fat oxidation and reduced food intake. Mary G. Enig reviewed in detail the medical factors and health benefits of medium-chain triglycerides. There has also been interest in MCTs from endurance athletes and the bodybuilding community. While there seem to be health benefits from MCTs, a link to improved exercise performance is weak.
Medical uses 
Medium-chain triglycerides are generally considered a good biologically inert source of energy that the human body finds reasonably easy to metabolize. They have potentially beneficial attributes in protein metabolism but may be contraindicated in some situations due to their tendency to induce ketogenesis and metabolic acidosis. Their use is not recommended for diabetics unless under supervised medical treatment and those with liver problems due to the added stress they may put on the organ.
Due to their ability to be absorbed rapidly by the body, medium-chain triglycerides have found use in the treatment of a variety of malabsorption ailments. MCT supplementation with a low-fat diet has been described as the cornerstone of treatment for primary intestinal lymphangiectasia (Waldmann's disease). MCTs are an ingredient in parenteral nutritional emulsions. Studies have also shown promising results for neurodegenerative disorders (e.g. Alzheimer's and Parkinson's Disease) and epilepsy through the use of ketogenic dieting.
Technical uses 
MCTs are bland compared to other fats, and do not generate off-notes (dissonant tastes) as quickly as LCTs. They are also more polar than LCTs. Because of these attributes, they are widely used as solvents for flavours and oral medicines and vitamins.
See also 
- Breckenridge, W. C.; Kuksis, A. (September 1967). "Molecular weight distributions of milk fat triglycerides from seven species". Journal of Lipid Research 8 (5): 473.
- M-P. St-Onge, P.J.H. Jones (2003). "Greater rise in fat oxidation with medium-chain triglyceride consumption relative to long-chain triglyceride is associated with lower initial body weight and greater loss of subcutaneous adipose tissue". International Journal of Obesity 27 (12): 1565–1571. doi:10.1038/sj.ijo.0802467. PMID 12975635.
- H. Tsuji, M. Kasai, H. Takeuchi, M. Nakamura, M. Okazaki, K. Kondo (2001). "Dietary Medium-Chain Triacylglycerols Suppress Accumulation of Body Fat in a Double-Blind, Controlled Trial in Healthy Men and Women". The American Society for Nutritional Sciences 131: 2853–2859. PMID 11694608.
- B. Martena, M. Pfeuffer, J. Schrezenmeir (2006). "Medium-chain triglycerides". International Dairy Journal 16 (11): 1374–1382. doi:10.1016/j.idairyj.2006.06.015.
- Takeuchi, H; Sekine, S; Kojima, K; Aoyama, T (2008). "The application of medium-chain fatty acids: edible oil with a suppressing effect on body fat accumulation". Asia Pacific journal of clinical nutrition. 17 Suppl 1: 320–3. PMID 18296368.
- St-Onge, MP; Jones, PJ (2002). "Physiological effects of medium-chain triglycerides: potential agents in the prevention of obesity". The Journal of nutrition 132 (3): 329–32. PMID 11880549.
- Papamandjaris, AA; MacDougall, DE; Jones, PJ (1998). "Medium chain fatty acid metabolism and energy expenditure: obesity treatment implications". Life Sciences 62 (14): 1203–15. doi:10.1016/S0024-3205(97)01143-0. PMID 9570335.
- Clegg, Miriam E. (2010). "Medium-chain triglycerides are advantageous in promoting weight loss although not beneficial to exercise performance". International Journal of Food Sciences and Nutrition 61 (7): 653–679. doi:10.3109/09637481003702114. PMID 20367215. Text "20367215" ignored (help)
- Enig, Mary. "Coconut: In support of Good Health in the 21st Century". Asia and Pacific Coconut Community, 36th CocoTech Meeting.
- Talbott, Shawn M. and Kerry Hughes. (2006). The Health Professional's Guide to Dietary Supplements. Lippincott Williams & Wilkins. pp. 60–63. ISBN 978-0-7817-4672-4.
- Wanten, GJ; Naber, AH (2004). "Cellular and physiological effects of medium-chain triglycerides". Mini reviews in medicinal chemistry 4 (8): 847–57. PMID 15544546.
- Vignes, S.; Bellanger, J. (Feb 2008). "Primary intestinal lymphangiectasia (Waldmann's disease)" (Free full text). Orphanet Journal of Rare Diseases 3: 5. doi:10.1186/1750-1172-3-5. PMC 2288596. PMID 18294365.
- Waitzberg, DL; Torrinhas, RS; Jacintho, TM (July–August 2006). "New parenteral lipid emulsions for clinical use". Journal of Parenteral and Enteral Nutrition 30 (4): 351–367. PMID 16804134.
- Krohn, Kathrin; Koletzko, Berthold (2006). "Parenteral lipid emulsions in paediatrics". Current Opinion in Clinical Nutrition and Metabolic Care 9 (3): 319–323. doi:10.1097/01.mco.0000222118.76536.ad. PMID 16607135. Text "16607135" ignored (help)
- Neal, E. G.; Cross, J. H. (2010). "Efficacy of dietary treatments for epilepsy". Journal of Human Nutrition and Dietetics 23 (2): 113–119. doi:10.1111/j.1365-277X.2010.01043.x. PMID 20487176. Text "20487176" ignored (help)
- Liu, Yeou-mei Christiana (2008). "Medium-chain triglyceride (MCT) ketogenic therapy". Epilepsia 49: 33–36. doi:10.1111/j.1528-1167.2008.01830.x. PMID 19049583. Text "19049583" ignored (help)
- Mensink RP, Zock PL, Kester AD, Katan MB (2003). "Effects of dietary fatty acids and carbohydrates on the ratio of serum total to HDL cholesterol and on serum lipids and apolipoproteins: a meta-analysis of 60 controlled trials". The American Journal of Clinical Nutrition 77 (5): 11461155. PMID 12716665.
- Akoh, Casimir C. (2006). Handbook of Functional Lipids. Washington, DC: Taylor & Francis. ISBN 0-8493-2162-X.
Further reading 
- Nagao, K.; Yanagita, T. (2010). "Medium-chain fatty acids: Functional lipids for the prevention and treatment of the metabolic syndrome". Pharmacological Research 61 (3): 208–212. doi:10.1016/j.phrs.2009.11.007. PMID 19931617. Text "19931617" ignored (help)
- Aoyama, T; Nosaka, N; Kasai, M (2007). "Research on the nutritional characteristics of medium-chain fatty acids". The Journal of Medical Investigation : JMI 54 (3-4): 385–8. PMID 17878693.
- Bach André C., Babayan Vigen K (1982). "Medium-chain triglycerides: an update" (PDF). The American Journal of Clinical Nutrition 36 (5): 950–962. PMID 6814231.
- Babayan, VK (1987). "Medium chain triglycerides and structured lipids". Lipids 22 (6): 417–20. doi:10.1007/BF02537271. PMID 3112486.
- Heydinger, Jenifer A., Dilip K. Nakhasi (1996). "Medium Chain Triacylglycerols". Journal of Food Lipids 3 (4): 251–257. doi:10.1111/j.1745-4522.1996.tb00072.x.
- Kaunitz, H. (1986). "Medium chain triglycerides (MCT) in aging and arteriosclerosis". Journal of Environmental Pathology, Toxicology and Oncology 6 (3–4): 115–121. PMID 3519928.
- Labarthe, François; Gélinas, Roselle; Des Rosiers, Christine (2008). "Medium-chain Fatty Acids as Metabolic Therapy in Cardiac Disease". Cardiovascular Drugs and Therapy 22 (2): 97–106. doi:10.1007/s10557-008-6084-0. PMID 18253821. Text "18253821" ignored (help)
- Medium chain triglycerides - Monograph. (October 2002). Alternative Medicine Review. Retrieved March 30, 2011.