Myths about MCT oil
A number of beliefs have formed around MCT oil — from “a fat that is not stored” to “fuel for champions.” Our editorial team checked popular claims against systematic reviews and clinical studies and explains which of them are true, which are exaggerated, and which are a myth.
Where the myths about MCT came from
MCT oil has come a long way from a narrowly specialized medical product to a fashionable attribute of “biohacking.” It was originally used in therapeutic nutrition — for fat malabsorption disorders — and later in the ketogenic therapy of epilepsy. Its popularity with a broad audience emerged along with the fashion for the keto diet and “bulletproof coffee.”
Marketing quickly turned real but modest effects into loud promises: “a fat that burns fat,” “clean energy for the brain,” “the secret of endurance.” Some of these claims have a scientific basis, some are based on exaggeration, and some are not confirmed at all.
Our editorial team examined the most common myths, relying on systematic reviews and clinical studies. The diagram below summarizes how strong the evidence is for the main expectations.
As can be seen, the best-proven claim is that MCT raises ketone levels. The remaining effects are either moderate or not confirmed at all.
Myth 1: MCT oil is the same as coconut oil
This is one of the most common misconceptions. Coconut oil is indeed one of the sources of raw material for MCT, but its composition differs substantially. About half of the fatty acids in coconut oil are lauric acid (C12), while caprylic and capric acids make up only a small proportion.
Lauric acid formally belongs to the medium-chain group, but it is metabolized more slowly, is partly absorbed via the lymphatic system, and raises ketone levels much less. In the study by Vandenberghe and colleagues (2017), coconut oil gave the weakest ketogenic response compared with MCT preparations.
In addition, coconut oil contains long-chain saturated fatty acids — myristic and palmitic. The review by Eyres and colleagues (2016) showed that coconut oil raises LDL cholesterol more than plant-based unsaturated oils.
Conclusion: coconut oil is a useful culinary product, but it does not replace MCT oil, and all studies of MCT effects cannot be automatically transferred to it.
Myth 2: MCT is not stored as fat and “burns” it
There is a grain of truth in this claim. MCT is indeed oxidized faster than long-chain fats and is deposited in adipose tissue to a lesser extent. The review by St-Onge and Jones (2002) described a slight increase in energy expenditure and enhanced satiety when ordinary fats are replaced with MCT.
However, “not stored at all” is not true. MCT contains about 8.3 kcal/g, and its calories count toward the overall energy balance. If you consistently consume more energy than you expend, body weight will increase regardless of the type of fat.
The meta-analysis of randomized studies by Mumme and Stonehouse (2015) showed that replacing long-chain triglycerides with MCT is accompanied by a small additional reduction in body weight and fat mass. The authors emphasized that the effect is modest and that the quality of some of the studies is limited.
So MCT can be a small helper in a weight-control program, but only as a replacement for other fats within a calorie deficit, not as a “magic” supplement.
Myth 3: MCT increases endurance and strength
The idea seems logical: if MCT is oxidized quickly, it can serve as a “fast fat” for working muscles and spare glycogen. It was precisely from this hypothesis that studies of MCT in sport began in the 1990s.
However, the results turned out to be disappointing. In the study by Jeukendrup and colleagues (1998), consuming MCT during prolonged cycling did not spare glycogen, and the final sprint even worsened, partly because of gastric discomfort. The reviews by Jeukendrup and Aldred (2004) and Clegg (2010) concluded that there is no convincing evidence of improved endurance.
As for strength and muscle mass, the situation is even simpler: MCT has no anabolic properties. It does not stimulate muscle protein synthesis and does not replace adequate protein intake.
The ACSM position on athlete nutrition (Thomas et al., 2016) does not include MCT among the recommended ergogenic aids. For endurance, carbohydrates taken during exercise are much better studied.
Other common myths
In addition to the three main myths, our editorial team regularly encounters other claims. Briefly about them:
| Claim | What the data say |
|---|---|
| “The more MCT, the better” | No. Large doses cause gastric upset, and the benefit does not increase proportionally |
| “MCT puts you into ketosis without a diet” | Partly. MCT raises ketones even with carbohydrates, but the level is usually moderate and short-lived |
| “MCT cures Alzheimer's disease” | No. Ketones as an alternative fuel for the brain are being studied, but MCT is not a proven treatment method |
| “Coffee with MCT replaces breakfast” | Such a drink provides energy, but contains almost no protein, vitamins, or fiber |
| “MCT oil is suitable for frying” | No. Its low smoke point makes it unsuitable for high-temperature cooking |
The claim about “energy for the brain” deserves a separate comment. Ketone bodies can indeed be used by neurons as fuel, and research groups are studying this in the context of age-related brain changes. However, there is a great distance between this and promises to “improve memory in a week.”
The myth of “ketosis without a diet” also needs clarification: a rise in ketones after a dose of MCT against the background of a normal diet is real, but it is not the same as stable nutritional ketosis with its metabolic changes.
Finally, the widespread claim that “MCT is good for everyone” ignores real contraindications: congenital MCAD deficiency, severe liver diseases, uncontrolled diabetes. For such people even a “natural” product can be undesirable. To avoid falling into the marketing trap, our editorial team advises following simple rules:
- Check whether the manufacturer refers to specific studies.
- Distinguish the effect of isolated fatty acids from the effect of coconut oil.
- Be skeptical of promises that sound too good.
Editorial conclusions
MCT oil has real but modest effects: it raises ketone levels, slightly enhances satiety, and may help a little in weight-control programs if it replaces other fats.
It is not coconut oil, does not “burn” fat on its own, does not improve endurance, and does not build muscle. Most of the loud promises are the result of marketing.
The sensible use of MCT is as part of a balanced diet, taking calories and tolerance into account.
For practical advice, also read our articles “How to take MCT oil,” “MCT oil: forms and which to choose,” and “Side effects of MCT oil.”
References
- St-Onge MP, Jones PJH. Physiological effects of medium-chain triglycerides: potential agents in the prevention of obesity. J Nutr. 2002;132(3):329–332.
- Mumme K, Stonehouse W. Effects of medium-chain triglycerides on weight loss and body composition: a meta-analysis of randomized controlled trials. J Acad Nutr Diet. 2015;115(2):249–263.
- Vandenberghe C, St-Pierre V, Pierotti T, Fortier M, Castellano CA, Cunnane SC. Tricaprylin alone increases plasma ketone response more than coconut oil or other medium-chain triglycerides: an acute crossover study in healthy adults. Curr Dev Nutr. 2017;1(4):e000257.
- Eyres L, Eyres MF, Chisholm A, Brown RC. Coconut oil consumption and cardiovascular risk factors in humans. Nutr Rev. 2016;74(4):267–280.
- Jeukendrup AE, Thielen JJ, Wagenmakers AJ, Brouns F, Saris WH. Effect of medium-chain triacylglycerol and carbohydrate ingestion during exercise on substrate utilization and subsequent cycling performance. Am J Clin Nutr. 1998;67(3):397–404.
- Jeukendrup AE, Aldred S. Fat supplementation, health, and endurance performance. Nutrition. 2004;20(7–8):678–688.
- Clegg ME. Medium-chain triglycerides are advantageous in promoting weight loss although not beneficial to exercise performance. Int J Food Sci Nutr. 2010;61(7):653–679.
- Thomas DT, Erdman KA, Burke LM. American College of Sports Medicine joint position statement: nutrition and athletic performance. Med Sci Sports Exerc. 2016;48(3):543–568.
Andriy Melnyk
A strength-sports coach and author of programs for beginner and intermediate levels. Writes about training planning.
