Typical example of a medium-chain triglyceride, containing three medium chain fatty acids (
caprylic acid in blue and
capric acid in red)
A medium-chain triglyceride (MCT) is a
triglyceride with two or three
fatty acids having an
aliphatic tail of 6–12 carbon atoms, i.e. a medium-chain fatty acid (MCFA). Rich food sources for commercial extraction of MCTs include
palm kernel oil and
coconut oil.
With regard to MCFAs, apart from the above listed straight chain (unbranched chain) fatty acids, side chain (branched chain) fatty acids also exist.[4]
Applications
Calorie restriction
A 2020
systematic review and
meta-analysis by Critical Reviews in Food Science and Nutrition supported evidence that MCT decreases subsequent energy intake compared to Long-Chain Triglycerides (LCTs). Despite this, it does not appear to affect appetite, and thus the authors stated that further research is required to elucidate the mechanism by which this occurs.[5]
Dietary relevance
Molecular weight analysis[6] of milk from different species showed that while milk fats from all studied species were primarily composed of long-chain fatty acids (16 and 18 carbons long), approximately 10–20% of the fatty acids in milk from
horses,
cows,
sheep, and
goats were medium-chain fatty acids.
Some studies have shown that MCTs can help in the process of excess calorie burning, thus weight loss.[7][8][9] MCTs are also seen as promoting fat oxidation and reduced food intake.[10] MCTs have been recommended by some endurance athletes and the
bodybuilding community.[11] While health benefits from MCTs seem to occur, a link to improved exercise performance is inconclusive.[10] A number of studies back the use of MCT oil as a weight loss supplement, but these claims are not without conflict, as about an equal number found inconclusive results.[12]
Pharma relevance
MCTs can be used in solutions, liquid suspensions and lipid-based drug delivery systems for emulsions, self-emulsifying drug delivery systems, creams, ointments, gels and foams as well as suppositories. MCTs are also suitable for use as solvent and liquid oily lubricant in soft gels. Brand names of pharma-grade MCT include Kollisolv MCT 70.[13]
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 a reported tendency to induce
ketogenesis and
metabolic acidosis.[14] However, there is other evidence demonstrating no risk of ketoacidosis or ketonemia with MCTs at levels associated with normal consumption,[8] and that the moderately elevated blood ketones can be an effective treatment for
epilepsy.[4]
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
Waldmann disease.[15] MCTs are an ingredient in some specialised
parenteral nutritional emulsions in some countries.[16][17] Studies have also shown promising results for epilepsy through the use of
ketogenic dieting.[4][18][19]
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 carrier oils or solvents for flavours and oral medicines and vitamins.[24]
^
abClegg, M. 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.
PMID20367215.
S2CID6128370.
^Talbott, Shawn M.; Hughes, Kerry (2006). The Health Professional's Guide to Dietary Supplements. Lippincott Williams & Wilkins. pp.
60–63.
ISBN978-0781746724.
^Rego Costa, AC; Rosado, EL; Soares-Mota, M (2012). "Influence of the dietary intake of medium chain triglycerides on body composition, energy expenditure and satiety: a systematic review". Nutr Hosp. 27 (1): 103–138.
doi:
10.3305/nh.2012.27.1.5369.
PMID22566308.
^Waitzberg, D. L.; Torrinhas, R. S.; Jacintho, T. M. (July–August 2006). "New parenteral lipid emulsions for clinical use". Journal of Parenteral and Enteral Nutrition. 30 (4): 351–367.
doi:
10.1177/0148607106030004351.
PMID16804134.
S2CID24109426.
^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.
PMID20487176.
^Viggiano, Andrea; Pilla, Raffaele; Arnold, Patrick; Monda, Marcellino; D׳Agostino, Dominic; Coppola, Giangennaro (August 2015). "Anticonvulsant properties of an oral ketone ester in a pentylenetetrazole-model of seizure". Brain Research. 1618: 50–54.
doi:
10.1016/j.brainres.2015.05.023.
PMID26026798.
^Rho, Jong M.; Anderson, Gail D.; Donevan, Sean D.; White, H. Steve (22 April 2002). "Acetoacetate, Acetone, and Dibenzylamine (a Contaminant in l-(+)-β-Hydroxybutyrate) Exhibit Direct Anticonvulsant Actions in Vivo". Epilepsia. 43 (4): 358–361.
doi:
10.1046/j.1528-1157.2002.47901.x.
PMID11952765.
S2CID31196417.
Bach, André C.; Babayan, Vigen K (1982). "Medium-chain triglycerides: an update". The American Journal of Clinical Nutrition. 36 (5): 950–962.
doi:
10.1093/ajcn/36.5.950.
PMID6814231.
Heydinger, Jenifer A.; Nakhasi, Dilip K. (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.
PMID3519928.
Labarthe, F. O.; Gélinas, R.; Des Rosiers, C. (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.
PMID18253821.
S2CID25297875.
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.
PMID19931617.