If you spend much time in keto, Paleo, or other niche diet circles there’s a decent chance you’ve seen people pouring spoonfuls of clear oil into their coffees, shakes, and salad dressings.
MCT oil. Medium-chain triglycerides. The uncommon fat that a lot of people claim will supercharge your health like never before. Is it legit? We took a look at the research to find five reasons you might want to consider adding it to your diet.
What Is MCT Oil?
- MCTs have a shorter “tail” of carbon atoms than most fats
This explanation might not sound simple, but put somewhat simply, most of the fat we eat is made of “long-chain” fatty acids, so named because the acids have a “tail” (technically an aliphatic tail) of more than fourteen carbon atoms. That counts as “long” when you’re talking about fat tails.
Medium-chain triglycerides, found predominantly in coconut oil but also in lower amounts in palm kernel oil and dairy, have tails of between six and fourteen atoms.
5 Benefits of MCT Oil
1. They Digest Quickly
- Because of the shorter tail, MCTs don’t require as much work to digest and can be used as energy more quickly
A common reason people consume fat (besides the taste, which is actually quite bland when it comes to MCTs) is because it’s filling and it slows digestion. But that’s not the case with MCTs. The shorter tail means they don’t need pancreatic bile to break down and they digest quickly.
So they’re useful if you want to consume a good hit of fat without that heavy, weighed down feeling that accompanies it — say, right before a workout — then MCTs do the job. And they do the job of providing fuel without spiking insulin, which can be important for some people who are focusing on improving insulin sensitivity or if they’re following a keto diet.
2. They Can Make the Keto Diet Easier
- Evidence suggests that MCTs help increase ketones in the blood, helping to reduce symptoms of fatigue that some experience on the low carb keto diet
Ketogenic diets entail consuming 50 to 60 percent of your calories from fat and about 20 to 30 percent from protein, with the idea being to go so low in carbohydrates (the body’s preferred fuel source) that the body needs to switch over to burning fat for fuel instead.
That process of “switching over” can take days, and a common symptom is a feeling of sluggishness and fatigue. MCTs seem to help reduce these keto side effects: a well-known randomized clinical trial found that when compared to sunflower oil, patients dosing with 30 milliliters of fat three times per day experienced fewer symptoms of “keto induction” when they were taking MCTs, which also produced higher levels of ketones in the blood.(1)
“As you’re changing over, that’s where people get that ‘fog’ and it seems in those first two or three weeks, MCTs are beneficial in eliminating that,” says Connecticut-based biochemist and strongman Michael Mastell. “That’s because it’s a faster energy source, and that’s really where the primary benefit of MCTs comes in.”
Ketosis means the body is relying more heavily on ketones for fuel, and MCTs dump the raw material for the ketone beta hydroxybutyrate right into the body. This may speed the process of getting into ketosis as well, as taking them technically increases the amount of ketones in the blood.(2)(3)(4)
“MCTs definitely increase ketones in the blood,” says Mastell. “The benefit is that the MCTs do it in a faster manner. So to draw a very loose analogy here, it’s like MCTs are dextrose as a carbohydrate source as opposed to a very complicated fibrous form of carbohydrates, which would be regular fat. That’s kind of the analogy: both types of fat are useful, but MCTs work much faster because it goes straight to the liver to be made into ketones.”
[Learn more: Is Keto Useful for Athletes?]
3. They May Improve Gut Health
- Some studies suggest that MCTs can help you to efficiently break down nutrients
To be clear, the main benefit of MCTs is that they digest quickly. There is some evidence for other health benefits, though, and one of them is gut health.
As a primer, digestive health and nutrient absorption has a lot to do with your gut bacteria: lots of different kinds of probiotic bacteria in your digestive tract is linked to better nutrient absorption, lower levels of inflammation, and other benefits.
There’s limited evidence that MCTs might be useful here. Animal studies on rats and pigs found that administering more MCTs improved nutrient absorption and bacterial gut health.(5)(6) A human study published in Nutrients also found that MCTs improved energy expenditure and metabolic health because of their ability to improve intestinal permeability and the bacterial environment.(7)
“I’ve definitely seen some things as far as certain IBS problems like diarrhea where they may have some benefit,” says Mastell. “There have been a few studies that have seen that if you have a really sensitive stomach it could potentially serve a benefit.”
He notes, though, that some of the gut health improvements may simply be because people tend to eat less sugar when they’re increasing their fat intake.
[Read more: 5 Things Most Athletes Miss About Digestive Health.]
4. They May Help With Exercise Performance
- Limited evidence suggests that MCTs can improve endurance by reducing lactate
The evidence here is very limited, but a lot of proponents point to a study published in the Journal of Nutritional Science and Vitaminology that found taking 1.5 teaspoons of MCT oil for two weeks resulted in athletes experiencing significantly lower levels of circulating blood lactate when compared to a group taking long chain fatty acids.(8) This resulted in the MCT group performing better in moderate and high intensity exercise.
5. They May Help With Brain Health
- By increasing ketones in the blood, MCTs may help to provide fuel to the brain
This effect seems to be limited mostly to impaired brains. With Alzheimer’s disease, for instance, the brain has difficulty using glucose for fuel but it doesn’t encounter the same problem with ketones, which is why MCTs and ketogenic diets are sometimes used.(11)
“The idea behind that is that ketones in general can cross the blood brain barrier, and so the thought process behind that is because it crosses the blood brain barrier that the brain can utilize those ketones as a source of energy,” says Mastell. “They’ve actually done some studies where people who have a certain genetic marker relative to Alzheimer’s are seeing a benefit to cognitive functioning and improvements in memory and learning effects.”
MCTs may also help with cognition among hypoglycemic diabetic patients and among memory impaired older adults.(12)(13) But a lot more research is needed here, and if you’re looking for ways to treat Alzheimer’s you need to speak with a physician rather than heading to your grocery store for coconut oil.
MCTs are unique among fats and they definitely seem to be useful if you’re looking for a source of fat that digests quickly, and they really hold promise for people following ketogenic diets who feel low on energy. It’s encouraging that there are benefits for exercise performance and brain and gut health, but for now, more research is needed. Talk to your doctor if you have any concerns.
Featured image via Imagepocket/Shutterstock
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2. Yeh YY, et al. Relation of ketosis to metabolic changes induced by acute medium-chain triglyceride feeding in rats. J Nutr. 1976 Jan;106(1):58-67.
3. Harvey CJDC, et al. The use of nutritional supplements to induce ketosis and reduce symptoms associated with keto-induction: a narrative review. PeerJ. 2018 Mar 16;6:e4488.
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9. Fushiki T, et al. Swimming endurance capacity of mice is increased by chronic consumption of medium-chain triglycerides. J Nutr. 1995 Mar;125(3):531-9.
10. Wang Y, et al. Medium Chain Triglycerides enhances exercise endurance through the increased mitochondrial biogenesis and metabolism. PLoS One. 2018 Feb 8;13(2):e0191182.
11. Cunnane SC, et al. Can Ketones Help Rescue Brain Fuel Supply in Later Life? Implications for Cognitive Health during Aging and the Treatment of Alzheimer’s Disease. Front Mol Neurosci. 2016 Jul 8;9:53.
12. Page KA, et al. Medium-chain fatty acids improve cognitive function in intensively treated type 1 diabetic patients and support in vitro synaptic transmission during acute hypoglycemia. Diabetes. 2009 May;58(5):1237-44.
13. Abe S, et al. Medium-Chain Triglycerides in Combination with Leucine and Vitamin D Benefit Cognition in Frail Elderly Adults: A Randomized Controlled Trial. J Nutr Sci Vitaminol (Tokyo). 2017;63(2):133-140.