Our digestive system is designed to turn the food individuals eat into nutrients, so the body can use these nutrients for energy, cell repair, and maintenance.
Gastrointestinal diseases affect an estimated 60 to 70 million Americans annually 4. Chronic digestive disorders such as irritable bowel syndrome, acid reflux and celiac diseases have become increasingly common and more diagnosed. Some digestive problems may be improved by reversing poor eating habits and by consuming specific ingredients and supplements.
In this issue we focus on the digestive advantages of MCT oils, especially C8 MCT oil, which is currently the most ketogenic MCT oil on the market. We review past literature and new literature highlights from peer-reviewed sources.
Background:
The most common form of dietary fats is known as triacylglycerols (TAGs) or triglycerides (TGs). In a C8 medium chain triglyceride (C8 MCT), there are three molecules of C8 (octanoic acid, caprylic acid, or caprylate) fatty acid molecules bound to each glycerol molecule (a 3 carbon molecule also known as glycerin). During digestion, bile salt conjugates (salt forms of bile acids), phospholipids, lysophospholipids (classes of polar lipids acting as emulsifiers) and specific lipases (fat-digesting enzymes) act to generate the glycerol backbone and three C8 fatty acid chains.
Long chain fatty acids (LCFA) with 12 (lauric acid, dodecanoic, as found in coconut oil) or more carbons are transported via chylomicrons (CM). Medium chain fatty acids (MCFA; C6, C7, C8, C9, and C10) are conversely transported in the hepatic portal system directly and rapidly to the liver.
Due to the rapid hepatic portal digestion of MCFAs, and less reliance on bile salts and lipases for digestion, dietary MCT oils and powders have been used to treat a number of digestive diseases and post-operative gut surgical conditions, since the 1960s. MCTs may be components of clinical formulations delivered in special medical foods and powders, delivered via enteral tube feeding or intravenously via total parenteral nutrition.
Results:
In recent years, MCTs have also been combined with olive oil and fish oil to offer energy as well as anti-inflammatory advantages over traditional soybean oil-based intravenous fat emulsions 1. Formulations containing soybean oil, MCTs, olive oil, and fish oil are known as SMOFs 2. One commercial SMOF is Smoflipid 5. SMOFs have been found to be safe and, relative to olive oil- or SMOF-based lipid emulsions, were associated with higher plasma concentrations of alpha-tocopherol, oleic acid, and the anti-inflammatory and structural omega-3 fatty acids eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) 2.
In other studies, formulations with MCTS and long chain triglycerides (LCTs), resulted in lower plasma triglyceride concentrations versus LCT formulations 3.
In a study with piglets, Smoflipid administration resulted in reduced inflammation, and a favorable accumulation of lipids in the brain, and improved growth and insulin sensitivity, relative to traditional soybean lipid emulsions 5, 9.
Mixtures of LCFA and MCFA on the same glycerol backbone in defined structural positions are known as structured triglycerides. Structured triglycerides with LCFA and MCFA showed improved protein economy, better liver tolerance and more efficient triglyceride elimination relative to physical (non-structured) mixtures of LCFA and MCFA 10.
With respect to digestive diseases, pancreatic insufficiency, impaired lymphatic chylomicron transport and fat malabsorption are conditions benefited by MCTs.
Recent studies show that conditions such as Gaucher disease with intestinal abnormalities 7, biliary atresia (bile ducts which help in fat digestion, do not open properly) in infants 6, and ascites (accumulation of fluid in the abdomen) 8, 11 can be successfully treated with MCTs.
Discussion and Conclusions:
Results of past literature, and recent literature reviewed above, suggest there are definitive advantages for including pure MCTs, alone and with other fatty acids (particularly in structured arrangements) for intravenous tube feeding (parenteral nutrition) applications and treating digestive diseases.
In persons without serious digestive diseases, but with milder issues digesting fats and high amounts of fat, MCTs may also be valuable. The rapid transport of MCTs to the liver generates energy via mitochondrial beta-oxidation (a pathway generating energy). Some MCFA are converted to ketone bodies (KBs) alleviating heavy reliance on insulin-dependent energy (carbohydrates in particular). The rapid transport, rapid energy production, and more delayed energy production from KBs (along with other non-energetic signaling roles from KBs), could benefit those with normal digestion seeking an energy boost.
REFERENCES
1. Biesboer, A.N. and N.A. Stoehr, A Product Review of Alternative Oil-Based Intravenous Fat Emulsions. Nutr Clin Pract, 2016. 31(5): p. 610-618.
2. Dai, Y.J., et al., Comparison of Formulas Based on Lipid Emulsions of Olive Oil, Soybean Oil, or Several Oils for Parenteral Nutrition: A Systematic Review and Meta-Analysis. Adv Nutr, 2016. 7(2): p. 279-286.
3. Devaud, J.C., et al., Does the type of parenteral lipids matter? A clinical hint in critical illness. Clin Nutr, 2016. 36(2): p. 491-496.
4. Everhart, J.E. and C.E. Ruhl, Burden of digestive diseases in the United States part I: overall and upper gastrointestinal diseases. Gastroenterology, 2009. 136(2): p. 376-386.
5. Guthrie, G., et al., Multi-omic profiles of hepatic metabolism in TPN-fed preterm pigs administered new generation lipid emulsions. J Lipid Res, 2016. 57(9): p. 1696-1711.
6. Macias-Rosales, R., et al., Effectiveness of Enteral Versus Oral Nutrition With a Medium-Chain Triglyceride Formula to Prevent Malnutrition and Growth Impairment in Infants With Biliary Atresia. J Pediatr Gastroenterol Nutr, 2016. 62(1): p. 101-109.
7. Mhanni, A.A., et al., Successful therapy for protein-losing enteropathy caused by chronic neuronopathic Gaucher disease. Molecular Genetics and Metabolism Reports, 2016. 6: p. 13-15.
8. Pan, W., et al., The application of nutrition support in conservative treatment of chylous ascites after abdominal surgery. Ther Clin Risk Manag, 2016. 12: p. 607-612.
9. Turner, J.M., et al., Liver Disease, Systemic Inflammation, and Growth Using a Mixed Parenteral Lipid Emulsion, Containing Soybean Oil, Fish Oil, and Medium Chain Triglycerides, Compared With Soybean Oil in Parenteral Nutrition-Fed Neonatal Piglets. JPEN J Parenter Enteral Nutr, 2016. 40(7): p. 973-981.
10. Wu, G.H., et al., Structured triglycerides versus physical mixtures of medium- and long-chain triglycerides for parenteral nutrition in surgical or critically ill adult patients: Systematic review and meta-analysis. Clin Nutr, 2016. 36(1): p. 150-161.
11. Zeanandin, G., et al., Prise en charge nutritionnelle d’une ascite chyleuse. Nutrition Clinique et Métabolisme, 2016. 30(1): p. 83-87.
2. Dai, Y.J., et al., Comparison of Formulas Based on Lipid Emulsions of Olive Oil, Soybean Oil, or Several Oils for Parenteral Nutrition: A Systematic Review and Meta-Analysis. Adv Nutr, 2016. 7(2): p. 279-286.
3. Devaud, J.C., et al., Does the type of parenteral lipids matter? A clinical hint in critical illness. Clin Nutr, 2016. 36(2): p. 491-496.
4. Everhart, J.E. and C.E. Ruhl, Burden of digestive diseases in the United States part I: overall and upper gastrointestinal diseases. Gastroenterology, 2009. 136(2): p. 376-386.
5. Guthrie, G., et al., Multi-omic profiles of hepatic metabolism in TPN-fed preterm pigs administered new generation lipid emulsions. J Lipid Res, 2016. 57(9): p. 1696-1711.
6. Macias-Rosales, R., et al., Effectiveness of Enteral Versus Oral Nutrition With a Medium-Chain Triglyceride Formula to Prevent Malnutrition and Growth Impairment in Infants With Biliary Atresia. J Pediatr Gastroenterol Nutr, 2016. 62(1): p. 101-109.
7. Mhanni, A.A., et al., Successful therapy for protein-losing enteropathy caused by chronic neuronopathic Gaucher disease. Molecular Genetics and Metabolism Reports, 2016. 6: p. 13-15.
8. Pan, W., et al., The application of nutrition support in conservative treatment of chylous ascites after abdominal surgery. Ther Clin Risk Manag, 2016. 12: p. 607-612.
9. Turner, J.M., et al., Liver Disease, Systemic Inflammation, and Growth Using a Mixed Parenteral Lipid Emulsion, Containing Soybean Oil, Fish Oil, and Medium Chain Triglycerides, Compared With Soybean Oil in Parenteral Nutrition-Fed Neonatal Piglets. JPEN J Parenter Enteral Nutr, 2016. 40(7): p. 973-981.
10. Wu, G.H., et al., Structured triglycerides versus physical mixtures of medium- and long-chain triglycerides for parenteral nutrition in surgical or critically ill adult patients: Systematic review and meta-analysis. Clin Nutr, 2016. 36(1): p. 150-161.
11. Zeanandin, G., et al., Prise en charge nutritionnelle d’une ascite chyleuse. Nutrition Clinique et Métabolisme, 2016. 30(1): p. 83-87.