Medium Chain Triglyceride Oil

XBrain’s MCT oil contains pure medium chain triglycerides from coconut and Coconut palm kernel oil. MCT triglycerides consist of fatty acids with short carbon chains, from 6-12 carbons, unlike the typical long chain triglycerides in the diet, which have 18-20 carbon chains. The shorter carbon chains in MCT oils make them easier to digest by pancreatic enzyme, and more easy to absorb in from the gastro-intestinal tract. They are transported rapidly to the liver, where they are beta oxidised in the mitochondria, rather than being incorporated into lipids for energy storage. MCToil, is therefore, a source of concentrated, easily available energy, which is used up by mitochondria, as soon as it is absorbed, rather than stored in fat deposits.

MCT oil Contains Triglycerides with Shorter Carbon Chains

Triglycerides are a form of fat molecules, they are found in foods, and they are the means by which lipids are transported in the blood. A triglyceride is an ester made out of a glycerol and three fatty acid chains. Most foods contain long chain triglycerides, in which the fatty acids contain 18,or more, carbon atoms. However, certain oils, most famously coconut and palm kernel oils contain triglycerides made out of fatty acids with shorter chains, between 6-12 carbons, such as capric acid and caprilic acid. These medium chain triglycerides are treated by the body quite differently than the normal, longer triglycerides.

The triglycerides in MCT oil are Easier to Digest, and Easier to Absorb

Because of the shorter carbon chains MCT triglycerides are much easier to digest by pancreatic enzymes. Unlike long chain triglycerides they do not require bile salts for digestion, and the evidence is that even people with pancreatic disorders are able to utilise them as nutrients. They passively diffuse from the gastro intestinal tract into the portal vein system, where they are transported in the bloodstream to the liver. In contrast normal long chain triglycerides enter the lymph system and are transported to the liver with lymph, a less direct route.

Along with other lipids, MCT have a higher energy concentration, as measured in calories per gram, than carbohydrate or protein. Unlike normal fats, however, they can be transported across the double membrane of mitochondria without the need for carnitine, and are readily beta oxidised to produce acetyl Co-A and ketone bodies, which can be used as energy sources by the brain, heart and peripheral tissues.  The medium chain fatty acids from MCT oil have a very low tendency to be used by the liver to build up more complex fats. Hence they provide an excellent energy source for performance athletes, malnourished patients, patients with malabsorption syndrome, and other people who need a ready, rich source of energy.

There is much interest in the role MCT oil might play in increasing performance and endurance in athletes. Athletes frequently sip carbohydrate drinks, to increase their blood glucose level and produce more fuel for their skeletal muscle during training or sport. MCT oil, provides a higher dose of energy than carbohydrates, but, unlike other oils, it is readily burned for energy, rather than being deposited in adipose tissue in the body. It therefore does not contribute to the fat content of the body, and by providing energy, it prevents protein breakdown by gluconeogenesis. The overall effect is increased endurance, and improved lean muscle to fat ratio.

In an animal study, the effect of a diet enriched in MCT oil was tested on the endurance of mice during swimming exercise. Mice fed on a diet high in MCT could swim much further than control mice fed on a carbohydrate and long chain triglyceride diet.

Unlike carbohydrates, MCT triglycerides do not raise blood sugar, causing an insulin spike. In fact they appear to have a slightly hypoglycaemic effect.  This protects against developing insulin insensitivity and type II diabetes.

MCT Oil Helps Support a Weight Loss Program

Surprisingly for a fat, medium chain triglyceride oil has been shown to be helpful for weight loss and fighting obesity in both animal and human trials. MCT oil is preferentially burned for energy in mitochondria, rather than being deposited in adipose cells, so it does not contribute to the fat stores in the body. MCT triglycerides have also been found to have a higher thermogenic effect after they are eaten. The thermogenic effect of food is the raising of the body’s temperature after a meal. Mostly this is due to the energy expenditure involved in digesting the food, and the exact amount of energy that must be used varies depending on the type of nutrient. Foods with a high thermogenic effect are obviously very useful to people attempting to lose weight, since the body in effect loses a proportion of the calories contained in the food.

Normally fats have a very low thermogenic effect, while proteins have the highest. As much as 20% of the calories contained in food high in protein is lost in the process of digesting it, while only 5% of the calories in lipids is lost to their thermogenic effect. However, MCT oil has a much higher thermogenic effect than long chain triglycerides, possibly because of their conversion into ketones.

One of the factors that makes losing excess weight particularly difficult is the fact that the body compensates for a lower energy intake by becoming more metabolically efficient, requiring less energy to perform the various functions of basal metabolism. The thermogenic effect of medium chain triglycerides helps counteract that to a certain extent, maintaining the body’s basal metabolism and ensuring that a reduction in calorie intake is reflect by weight loss.

The fact that MCT oil triglycerides are readily burned in mitochondria, producing ketones, which can be used as an energy source by other organs, ensures that muscle proteins are protected from being broken down through gluconeogenesis in the liver for glucose. Muscle wasting is another negative aspect of reduced calorie intake, which also prevents the loss of excess fat, and causes a reduction in basal metabolism; muscle tissue requires more energy for maintenance than non-muscle tissue. By protecting skeletal lean muscle mass from being catabolised for energy MCT oil again counteracts the effects of a calorie-restricted diet on basal metabolism.

Finally the inclusion of MCT oil in the diet appears to decrease appetite, making the consumption of fewer calories easier. It is possible that this is achieved through the production of ketones, which have an appetite suppressing effect. In this way a weight loss diet supplemented with MCT oil, mimics the effects of the Atkins diet.

MCT Oil and Ketogenesis

Ketone bodies are three water soluble molecules, acetone, acetoacetic acid, and beta-hydroxybutyric acid, which are produced in the liver from acetyl-CoA, a by product of the beta oxidation of fatty acids. Ketone bodies can be used as sources of energy by tissues in place of glucose. Crucially, because they are water soluble, they can cross the blood-brain barrier, and be utilized for energy by brain cells, which cannot use fatty acids. Ketone bodies are normally produced in the liver when glucose levels are low, and after depleting glycogen stores. The condition in which the liver produces increased levels of ketone bodies is known as ketogenesis, and is most often associated with starvation. However, certain diets, which severely restrict carbohydrate intake can also be ketogenic, since in the absence of carbohydrate the body is forced to use fats as a source of energy.

A diet rich in medium chain triglycerides can result in enhanced production of ketone bodies, an alternative to glucose as a source of cellular energy, in the liver. MCT triglycerides are generally more ketogenic than long chain fatty acids. A ketogenic diet has long been known to be helpful in controlling seizures in people with epilepsy. A ketogenic diet was used as a remedy for epilepsy early in the last century, although it was later abandoned as anti-convulsant pharmaceuticals began to be used. Interest in it was reawakened in the 1990s after it was popularised by the Hollywood producer Jim Abrahams who found that it could effectively control his son’s severe seizure attacks.

In recent years there has been interest in using a ketogenic diet to control other neurodegenerative conditions such as Alzheimer’s, or even autism. Recent research has raised the possibility that Alzheimer’s disease is caused by an insulin insensitivity in the brain. The study by a team in the Perelman School of Medicine at the University of Pennsylvania, uncovered abnormalities in insulin and insulin-like growth factor pathways in non-diabetic people with Alzheimer’s disease. Glucose is the brain’s preferred source of energy, and since insulin signalling is necessary to cause cells to take up insulin, the research study, published in the Journal of Clinical Investigations, suggests that Alzheimer’s disease might be caused by brain cells becoming insulin insensitive, causing them to stop taking up nutrients, and leading to function failure and death. Brain cells cannot take up fatty acids to use as energy, however they can use ketone bodies produced from fatty acids in the liver, in a process that does not depend on glucose.

Although clinical trials testing the efficacy of a ketogenic diet in treating Alzheimer’s have just began, there is a lot of anectodal evidence that suggests that patients who consume a diet high in MCT oil show a marked improvement in their cognitive function. The theory is that an MCT supplemented diet creates a raised level of ketone bodies in the blood, which can be taken up by the brain cells, providing an alternative energy source to the glucose that they can no longer use, restoring brain function, and preventing cell death.

A ketogenic diet is a low carbohydrate, high fat diet, which forces the body to use fatty acids rather than glucose as the main source of energy. Normally triglycerides are cleaved into glycerol and fatty acids in a process known as lipolysis. The fatty acids are then burned in the mitochondria in a process known as beta-oxidation, which produces acetyl-CoA which can be used in the citric acid cycle to produce energy.

Although most tissues can use fatty acids for energy, when glucose levels are low, the brain is not able to, since fatty acids cannot cross the blood-brain barrier. The liver, however, is able to convert fatty acids into ketone bodies, which are water soluble and can cross the blood-brain barrier. In the liver mitochondria, acetyl-CoA can be converted to the three types of ketone bodies, acetone, acetoacetic acid, and beta-hydroxybutyric acid. These can then be taken up by the cells in the brain, which can convert them back acetyl-CoA. Acetyl-CoA can then be used for energy production in the cells by enteric the citric acid cycle.

Fatty acids obtained from MCT oil are more ketogenic than long chain fatty acids, and they are metabolized in the mitochondria through beta-oxidation soon after they are consumed, not just under conditions of low glucose levels. Because of this, it is not necessary to restrict carbohydrates as drastically to produce a ketogenic diet, when MCT oil is consumed.

MCT Oil Triglycerides do not Contribute to Atherosclerosis

Unlike saturated long chain fatty acids, MCT triglycerides do not contribute to high triglyceride or LDL-cholesterol serum levels, important factors in developing atherosclerosis, the hardening of arteries which leads to heart disease. Partly this is down to the fact that medium chain triglycerides rapidly enter the mitochondria and undergo beta-oxidation rather than being deposited in fat reserves and circulating in the blood.  Unlike triglycerides that contain lauric, myristic or palmitic fatty acids, they do not produce sterols as a byproduct of their metabolism, and hence to not contribute to cholesterol synthesis by the body.

In studies on animals, those fed a diet high in medium chain triglycerides, showed that MCTs limit the deposition of cholesterol in all tissues. That, unlike long chain triglycerides they are not thrombogenic, they do not cause the blood to clot, and hence decrease the risk of ischaemic strokes, and that the lifespan of animals fed on an MCT rich diet is longer, than on control animals fed on a diet high in long chain triglycerides.

Further Reading

A review of the benefits of medium chain triglycerides:

http://ajcn.nutrition.org/content/36/5/950.full.pdf

Improved exercise indurance on an MCT diet:

http://jn.nutrition.org/content/125/3/531.long

MCT oil and weight control:

http://www.ncbi.nlm.nih.gov/pubmed/22566308

http://jn.nutrition.org/content/132/3/329.long

http://www.ncbi.nlm.nih.gov/pubmed/8732772

MCT oil and the ketogenic diet:

http://www.ncbi.nlm.nih.gov/pubmed/23515148