If you’ve found yourself on any ketogenic diet forums full of fat-loving people, you’ve likely heard of MCT oil. It’s also now a fixture at health food shops so you may have seen the stuff while shopping for quinoa or almond butter. As with many trending foods, fans of MCT oil boast about its numerous health benefits including rapid weight loss, improved athletic performance, and better brainpower.
If you believe the hype you might be wondering if spooning it up can help you ditch a few pesky pounds or get to the finish line quicker. Does MCT oil work? How much do I need? Is this just another supplement fad that will do little more than deliver liquid calories? Read on for what triathletes need to know about MCT oil.
What Exactly Are MCTs?
“MCT” is an abbreviation for the oil’s chemical structure: medium-chain triglycerides. “Medium-chain” refers to the chemical arrangement of the carbon atoms and, depending upon the number of carbon atoms in a chain, are classified as short, medium, or long chain.
MCTs contain three main types of fatty acids: lauric, capric, and caprylic acids. All are classified as medium-chain, but lauric is a somewhat longer chain than the others. Most often, the MCT products on store shelves are derived from processing coconut oil or palm kernel oil, which contain varying amounts of these fats. In contrast, foods such as avocado, nuts, fish and olive oil contain long-chain triglycerides.
The length of the fatty acid chain determines the digestion process and what makes MCTs unique is the way the body breaks them down. Compared to other fats, digesting MCTs is much faster and simpler. They do not require bile or pancreatic enzymes—therefore, they are delivered more quickly to the liver where they are metabolized and used for energy, according to this study in the Clinical Nutrition Journal. That makes MCTs more likely to be oxidized into energy rather than stored as fat when compared to longer-chain fatty acids.
MCT Oil and Its Potential Benefits
One tablespoon of MCT oil contains about 130 calories, 14 grams of fat, and no protein or carbs. While research is ongoing, it has some potential benefits for athletic performance and weight loss.
MCT oil tends to be absorbed more quickly, thanks to its medium-length fatty acids, making its energy immediately available to power your workouts. Research does suggest that consuming MCTs daily leading up to a workout can suppress the utilization of carbohydrate for energy production during moderate-intensity exercise because of increased utilization of fatty acids for generating energy. This could be beneficial at helping to preserve precious carbohydrate stores for times when you need to ramp up the pace and also help stave off the dreaded bonk. So if most of your workout takes place at about 60% of your maximum workload, MCT supplementation may allow you to use a higher percentage of fat energy during this time—leaving behind more carbs for times when your intensity rises to closer to your max. Of course, your diet will need to include enough carbohydrates so that those stores are available in the first place. (This would not be the case if following a ketogenic diet.)
An investigation in the Journal of the International Society of Sports Nutrition did find that trained athletes were able to use more MCTs during a higher intensity effort than longer-chain fats, which makes sense when you consider they are oxidized more rapidly. So taking MCTs may help raise the bar for what intensity you can use fats as a useful fuel source. One report suggests that an MCT-containing diet can help our cells generate more mitochondria which—in theory—would allow us to produce more of the energy needed for brag-worthy workouts. Also, MCT intake may lower the build-up of blood lactate during exercise which can lower the perceived exertion of a workout thereby helping you push the pace, according to another study.
MCT Oil Caveats
But not all research has shown that consuming MCTs before and during endurance exercise results in a noticeable change in substrate metabolism and improved performance. Plus, there can be a greater risk for gastrointestinal symptoms with MCT use including diarrhea (that is always fun halfway through a run) that can hinder performance, so it’s vital to experiment using it during training and not on race day.
Despite some promising findings, we are still a ways off from being able to crown MCTs as a performance booster. We simply don’t know enough about its impact on metabolism when working up a sweat, how much is needed, and what is the proper timing of consumption. Plus, some research says that there might be differences among the sexes on the impact MCTs have on fat oxidation during exercise.
Considering that MCTs are more likely to be metabolized into energy than other forms of fat, it’s not surprising that it has been hailed as a way to boost your fat-burning metabolism and to help improve body composition.
MCTs as a Replacement
An analysis that was published in the Journal of the Academy of Nutrition and Dietetics found that MCT oil consumption resulted in slightly reduced body weight, total body fat, and waist circumference when compared with consumption of long-chain triglycerides. But the key is that LCTs are replaced with MCTs in the diet and not simply added on top, which would add enough calories to lower any chances for shedding body fat. The study authors also mention that many investigations suffer from limitations like low sample sizes and short time frames.
One study did show that when overweight men consumed the same number of calories from MCTs or olive oil for a month they lost more adipose tissue (fat mass) when their diets included the former, likely owing to higher rates of energy expenditure and fat oxidation. So if someone has a goal of trimming down it could be beneficial to swap out other oils in their diet for the MCT version—such as making salad dressings with MCT oil instead of olive oil. But if this benefit would be extended to athletes who simply want to drop a pound or two is not known.
Additionally, there might be a satiating quality of MCTs by triggering the body to release the hormones leptin and peptide YY, both of which decrease appetite and signal the body to stop eating, according to the European Journal of Clinical Nutrition. MCTs, when added to a meal may also slow gastric emptying, which is research speak for reducing the speed at which food is digested. In the end, these effects could lead to fewer overall calories consumed, which can potentially result in weight loss. However, if you are training hard with respect to intensity and volume, you likely need to eat more not less, so this function of MCTs is not one you should necessarily be striving for as an athlete.
Overall, the available research that suggests MCTs can help in the battle of the bulge and keep you lighter on your feet is limited and inconclusive. Truth be told, the thought that simply adding a tablespoon or two of MCT oil to your diet without cutting back elsewhere will help keep you trim is wishful thinking. Ultimately, training is a more productive way to torch calories than spooning up a fatty supplement.
And it’s important to remember that since MCT oil is essentially 100% fat you don’t get any of the beneficial bioactive compounds found in other oils like extra virgin olive oil and avocado oil. So it may not be wise to ditch those completely.
How to Take MCT
While MCT oil is generally safe for consumption, it can present certain gastric woes. To play it safe, start with a small amount each day, and increase as tolerable. Try starting with one teaspoon a day, and working your way up to a tablespoon to two each day. Additionally, taking MCT oil on an empty stomach may bring more discomfort than taking it with food. Beyond spoon to mouth, you can use MCT oil in salad dressings or blended into smoothies as it is rather flavorless. Another option is MCT powder such as this one from Nutiva which can be stirred into oatmeal, coffee, or yogurt.
The MCT Bottom Line
Are there potential benefits of taking MCTs for athletic performance and body composition? Yes. Do you need it to achieve podium results and a slimmer waistline? Absolutely not. If you want to try MCT oil go for it, just don’t expect it to transform your fitness and physique the same way that consistent training and healthy eating will.