Medium-Chain Triglyceride Benefits: The Hard Science.
Part 1: Can MCT be stored as fat?
Note: Laurin is pure CocoMCT: Medium Chain Triglycerides plus Lauric Oil, all drawn from and representing the very best of coconut oil. In the series of articles that begins with this article we will draw on hard scientific research to show the health benefits that come from MCT, which comprises the majority of the oil that makes up Laurin.
The health benefits of Medium Chain Triglycerides (henceforth, MCT) are well-publicized all over the Internet, whether in conjunction with coconut oil or by themselves. In turn, the frequent repetitions of these benefits draw occasional challenges from critics. It doesn’t help that these health benefits are often presented without citing any specific studies or references, giving people the impression that the MCT is presented just like “snake oil”, and is just as baseless.
In this four-part series we will refer to solid studies in favour of MCT. In the first part we will refer to proofs that taking MCT is not stored as fat, or at least only in negligible amounts that are ultimately outweighed by the overall weight reduction that MCT can cause. In the second part we will refer to proofs that MCT can help manage obesity and adipose tissue (in other words, body fat) and assist in weight reduction. The third will be about MCT’s ability to enhance brain health. The fourth will focus on MCT’s ability to help Alzheimer’s patients.
MCT and Adipose Tissue (Fat Deposits):
That MCT aids in the reduction or management of obesity is beyond challenge, and may be considered as established fact. Before we go on to the different aspects of how it helps manage obesity, we need to deal with the basic question: is MCT itself stored as harmful fat? The answer: MCT is not stored as fat, or at least is stored only in very small amounts that do no harm. The reason is explained by a prestigious reference work on lipids, published in 2012:
When absorbed directly, MCTs enter the blood circulatory system through the portal vein and carried to the liver where they are oxidized to ketones. This is because in the mitochondria, transport of MCTs does not require carnitine palmitoyl transferase, a rate-limiting enzyme of b-oxidation. The mostly catabolic fate of MCFAs is evident by the fact that dietary MCTs reduce blood triglyceride levels during human intervention trials. Thus, dietary MCTs induce thermogenesis and do not contribute to weight gain since they are not deposited in the adipose tissue. This has been demonstrated in diet intervention trials involving hypertriglyceridemic human subjects where MCTs reduced body mass index, hip circumference, waist-hip ratio, total abdominal fat, visceral fat, body fat mass, and waist circumference. MCT diets also reduced blood levels of several types of LDL as well as LDL-cholesterol to greater extent than traditional oil that contained long-chain triglycerides. Therefore, MCTs may be used as a means of preventing and treatment of obesity, though the exact molecular mechanism of action has not been fully elucidated apart from the thermogenic effects. (Aluko 2012: 24)
A Japanese medical article published in 2001 states more succinctly:
Medium-chain triacylglycerols (MCT), composed of medium-chain fatty acids such as octanoic and decanoic acids, are readily hydrolyzed by lingual and gastric lipases. The medium chain fatty acids formed are absorbed through the portal system without resynthesis of triacylglycerol in intestinal cells, are subjected predominantly to b-oxidation in the liver, and are not stored as fat. Consequently, MCT constitute a good energy source for patients with pancreatic insufficiency and fat malabsorption as well as preterm infants with pancreatic juice and bile acid insufficiency (Tsuji et. al 2001: 2853)
Octanoic refers to C8 (which we more frequently refer to as caprylic acid) while decanoic would refer to C10 (which we more frequently refer to as capric acid).
An older article even gives to MCT the appellation “fatless fats”, because they are, at the very least, not stored well by the body:
MCT and MCFA reveal distinct physicochemical and metabolic properties when compared to LCT and LCFA (4). Schematically, the former lipids either follow specific and shorter pathways or undergo more rapidly the same converting steps as those taken by the latter. As a result, MCT appear as an unconventional fat and are proposed for use either in oral/enteral nutrition when the digestion, absorption, or transport of LCT is impaired or in parenteral nutrition when a rapid energy supply is desired. These aspects are in keeping with studies showing that the fatty acids delivered by MCT are abundantly oxidized and poorly stored within tissues. As a logical application of these observations, the claim that MCT formulas might contribute to the control of body weight in human subjects has been repeatedly emphasized over the last decades, more especially as MCT were regarded as “light fats” and even as “fatless fats”. (Bach 1996: 708-709)
The Nutrition Review in an article published in 2013 that exhibits the same caution as the 1996 article, while adding that its overall impact is to enhance the burning of body fat deposits:
In addition to their lower caloric content than LCTs, MCTs are not stored in fat deposits in the body as much as LCTs. Furthermore, MCTs have been shown to enhance thermogenesis (i.e., fat burning). So MCTs seem to offer a triple approach to weight loss – they (1) have a lower calorie content than other fats, (2) are minimally stored as fat, and (3) contribute to enhanced metabolism to burn even more calories. (Dean and English 2013: Paragraph 6)
Perhaps the best scientific article directly dealing with MCT and body fat is "The application of medium-chain fatty acids, edible oil with a suppressing effect on body fat accumulation", published in the Asia-Pacific Journal of Clinical Nutrition in 2008. Although the article as a whole pushes for a synthetic product that merely incorporates the goodness of MCT, it admits that MCT by itself has a positive effect when it comes to helping alleviate obesity. The most important passages are in the 2nd and 3rd pages of the study (pp. 321-322). It is impressive that the article speaks on the "body fat accumulation-suppressing effect" of MCT. This is stronger than saying that MCT assists in dieting or in weight loss, or that it is not stored as fat. This finding makes it clear that, whether MCT is stored (in very small amounts) in the body or not, its overall effect is to reduce body fat, not add to it:
MCT is less accumulated as body fat than general edible oil which consisted in LCT in laboratory animals, suggesting that MCT prevents obesity, being useful for the prevention of lifestyle-related disorders. However, the suppression of body fat accumulation by MCT had not been fully clarified in humans. Thus, we performed a large-scale study on the body fat accumulation suppressing effect of MCT in humans. A double-blind study was performed in healthy subjects under strict dietary management). Seventy-eight subjects slightly fatter than the average (mean BMI=24.7) ate bread containing 14 g of the test oil daily as breakfast. A total of more than 10,000 lunches and suppers were prepared so that the subjects ate identical meals for 12 weeks. Eating between meals and beverages were also controlled, and the subjects were strictly controlled to ingest 2200 kcal/day containing 60 g of lipids. For body fat measurement, the air displacement method was used for accuracy. In the subjects with a BMI of 23 or higher (slightly fat), the body weight loss was larger in the MCT ingestion group than in the common edible oil ingestion group. (Aoyama 2008: 321)
MCT is rapidly digested and absorbed, and suppresses body fat accumulation. (Aoyama 2008: 322)
We have now established that there is enough basis in the publicly-available scientific literature to state that MCT is not stored as fat, and even suppresses body fat accumulation. In the following articles we will show how MCT aids in weight loss and, perhaps more importantly, how it enhances brain health and helps combat diseases such as Alzheimer's.
Aoyama, T., Kojima K., Sekine S., and Takeuchi, H. (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, (S1):320-323
Aluko, R.E. (2012): “Bioactive Lipids” in Functional Foods and Nutraceuticals. Food Science Text Series © Springer, 2012
Bach, A.C, Frey, A., and Ingenbleek, Y.,(1996): The usefulness of dietary medium-chain triglycerides in body weight control: fact or fancy? Journal of Lipid Research Volume 37: 708-726.
Dean, Ward and English, Jim, (2013): "Medium Chain Triglycerides (MCTs) - Beneficial Effects on Energy, Atherosclerosis and Aging" April 22, 2013, Nutrition Review:http://nutritionreview.org/2013/04/medium-chain-triglycerides-mcts/
Tsuji H., Kasai M., Takeuchi H. et. al. (2001): Dietary Medium-Chain Triacylglycerols Suppress Accumulation of Body Fat in a Double-Blind, Controlled Trial in Healthy Men and Women. Journal of Nutrition, 131: 2853-2859.