MCT - Medium Chain Triglycerides

Medium Chain Triglycerides (MCTs) are fats that are shorter in length than most normal dietary fats (Long Chain Triglycerides or LCTs). MCTs are found in coconut oil, palm kernel oil and butter, as well as being available in pure form.

• MCT produces Ketones even without being part of a Low Carbohydrate Diet.
  • Ketone levels are higher when on a Low Carbohydrate Diet.
  • Carbohydrate consumption with the MCT will reduce ketone levels.
  • Higher intake of MCT will produce higher ketone levels.
  • Fasting will increase ketone levels from MCT.
• MCT can produce nausea, vomiting, stomach cramps and diarrhea. Adaptation and mixing with other foods can reduce the problems.
• There are initial indications that MCT will reduce the symptoms of Alzheimer's and other memory problems.

This article is under construction. Caution: This a skeleton article, so only a rough outline exists. This may consist of semi-completed sections, isolated bullet point and notes to the author. You are welcome to read what exists so far, and feedback is welcomed. Email "feedback <at> fellrnr <dot> com"

1 MCT and the Ketogenic Diet

Because MCT will increase Ketone Levels without needing Carbohydrate restriction, they are often used for epilepsy treatment. Small amounts of MCT can be used to increase the ketone levels, or to reduce elevated cholesterol levels while on the Ketogenic Diet. Larger amounts of MCT are the basis of the MCT Diet, which allow for a greater carbohydrate intake than the traditional Ketogenic Ratio Diet and therefore more food choices.

2 MCT Cost

MCT is expensive. I've used pure MCT products like Premium MCT Gold and Dr. Bernd Friedlander MCT Oil, and they are all around $1/oz. You can buy coconut oil, which is about 60% MCT (see below for details), but products like Nutiva Organic Extra Virgin Coconut Oil are about $0.50/oz, which works out around the same price. (Note that products like TwinLab Mct Fuel contain only about 50% MCT.)

3 MCT and Ketone Levels

A 1969 study looked at how ketone levels changed with MCT. Subjects were non-obese healthy adults, mostly on a high carbohydrate diet who did not perform any exercise beyond slow walking after taking the MCT. Unless otherwise stated, the subjects consumed only water after taking the MCT. The study measured breath acetone, which is likely to peak sometime after blood AcAc or BOHB levels. (Note that from another study, Acetone at 1.0 µg/100ml breath might indicate blood ketones of BOHB 1.5 mmol/L and AcAc of 0.7 mmol/L, 5.0 µg/100ml might be BOHB 2.7 mmol/L and AcAc of 1.4 mmol/L. See below for details.)

This is the time course of a single 30ml dose of MCT. You can see the peak occurs after 6 hours, though the blood AcAc levels probably peak sometime earlier.	The effects of different doses of MCT on breath acetone. The 10, 30, 50, and 75ml doses produced a linear, proportional increase in Ketones, but the 100ml is disproportionately large. Also note that the peak occurs later for larger doses.
Even though MCT produces ketones without carbohydrate restriction, it is clear from this graph that carbohydrate taken at the same time as the MCT will inhibit ketone production. Note that from a low carbohydrate perspective, this is quite a lot of sucrose that is ingested.	This shows the linear relationship between maximum breath acetone and the sucrose dose.
The effect of 78g of sucrose on the dose/response of MCT on Ketones. The sucrose reduces ketone levels for all doses of MCT, but the effect is greater at higher MCT levels.	The effect of fasting on response to 30ml MCT. The dotted line and triangles show the ketone levels from fasting alone. The ketone levels in response to MCT are larger after fasting, and the study noted that a low carbohydrate response resulted in a larger ketone response than a mixed diet. (There was only one subject on a low carbohydrate diet, so no statistical inference can be drawn.)

A study showed that giving 40ml of MCT raised blood BOHB levels to 0.43-0.68 mmol/L. Another study showed that 1mg/Kg body weight of MCT raised blood ketone levels to 0.4 mmol after 30 minutes and 0.8 after 120 minutes, falling to 0.7 after 300 minutes:

The ketone levels after 1mg/Kg body weight. The units are in mg/dl, so divide by 10 to get the more usual mmol (both BOHB and AcAc have similar conversion ratios).

3.1 Calculating Blood Ketone Levels from Breath Acetone

A study looked at the correlation between breath acetone and blood ketone levels. The results indicated the following relationships between breath acetone in nmol/L and blood ketone levels in mmol/L.

• Acetoacetate (AcAc): Y = AX^B + C, where A = 3.4884, B = 0.0803, C = -4.6065.
• Hydroxybutyrate (BOHB): Y = AX^B + C, where A = 5.1365, B = 0.0864, C= -6.5048.
• Acetone: Y = AX^B + C, where A = 2.2177, B = 0.1900, C = -5.6040.

To convert from µg/100ml used above to nmol/L:

• 1 ug/100 ml is 0.001 mg/dL.
• 0.001 mg/dL is 0.000172 mmol/L.
• 0.000172 mmol/L is 172 nmoml/L.

Plugging this conversion into the above equations, we get:

ug/100 ml	mg/dL:	mmol/L:	nmoml/L	BOHB	AcAc	Acetone	Total
1.0	0.001	0.000172	172	1.5	0.7	0.3	2.5
2.0	0.002	0.000344	344	2.0	1.0	1.1	4.1
3.0	0.003	0.000516	516	2.3	1.2	1.7	5.1
4.0	0.004	0.000688	688	2.5	1.3	2.1	5.9
5.0	0.005	0.00086	860	2.7	1.4	2.4	6.5

4 MCT and digestive distress

MCT frequently causes digestive problems, including nausea, vomiting, stomach cramps and diarrhea. There may be several factors that influence the level of digestive distress:

• Quantity. Higher quantities of MCT are more likely to cause digestive distress. One study found that 50g of MCT caused all subjects digestive problems, but 30g only caused problems in 10% of subjects.
• Adaptation. There is adaptation that occurs with consumption of MCT over several days. Two studies showed a reduction in digestive distress over time; in one, subjects were given 34g/day for 7 days and the other, 60g/day for 14 days. By the end the subjects' distress had reduced or disappeared.
• Other Foods. Consuming MCT with other foods reduces the digestive distress.

Personally, I found that even after weeks of taking MCT, I could not consume it on its own without incurring dramatic digestive problems. Mixing MCT with other foods greatly reduced, but did not completely remove, the issues.

5 MCT and Athletic Performance

To follow.

6 MCT and Hypoglycemia

To Follow.

7 MCT and Alzheimer's

There is evidence that MCT can help reduce peoples' memory impairment without carbohydrate restriction. A study using elderly dogs showed a long lasting improvement in cognitive ability with MCT supplementation. There are other anecdotal reports of MCT helping with Alzheimer's symptoms.

8 Types of MCT

The 'medium chain' in 'medium chain triglycerides' refers to the length of the chain carbon atoms. Generally, chain lengths of 6 to 12 carbon atoms (C6 to C12) are considered 'medium'. The most common source of MCTs is in Coconut Oil, and typically pure MCT is refined from Coconut Oil. The mixture of oils in most MCT reflects that of Coconut Oil. MCT oils are fully saturated.

8.1 Sources of MCT

The composition of common sources of MCTs is shown below:

	Coconut Oil		Palm Kernel Oil		Butter
Fatty Acid	Typical %	Range %	Typical %	Range %	Typical %
6:0 Caproic	0.5	0.4-0.6	0.2	0.1-0.5	2.0
C8:0 Caprylic	7.8	6.9-9.4	3.3	3.4-5.9	1.2
C10:0 Capric	6.7	6.2-7.8	3.4	3.3-4.4	2.5
C12:0 Lauric	47.5	45.9-50.3	48.2	46.3-51.1	2.6
Total MCT	62.5	59.4-68.1	55.1	53.1-61.9	8.3

9 Calories in MCT

An animal study has shown that overfeeding that includes large quantities of MCT produced 20% less weight gain than the same level of overfeeding with LCT. The rats were fed a diet of 50% of calories as fat, with the MCT diet providing 45% of calories from MCT. The rats had similar levels of activity and insulin. This may because MCTs are raise body temperature (thermogenesis). MCT has is often considered to have a slightly lower calorie density of 8.3 Calories/gram compared with 9.1 Calories/gram for LCT. However, if thermogenesis is taken into account, a value of 6.72 Calories/gram would be more appropriate. This may be critical when using the MCT Diet if calorie intake is restricted. Given the density of MCT is 0.93 - 0.96 grams/ml, 15ml of MCT would be 95 Calories assuming 6.72 Calories/gram rather than 118 Calories assuming 8.3 Calories/gram.

10 MCT and Weight Loss

MCTs are sometimes recommended for weight loss. One study compared MCTs with Olive Oil and found a greater weight loss with MCTs. There is some evidence from an animal study that MCTs may be less palatable than other fats. However, an analysis of animal studies indicates that generally, replacing other fats with MCT does not reduce calorie intake. Based on my personal experiences with MCT, I would suspect that any weight loss benefit comes from the appetite reduction that comes from the associated nausea.

11 MCT Safety

MCT is considered safe at 1mg/Kg of body weight, and MCT has been shown as effectively non-toxic in high dose animal studies.

12 My Experiences with MCT

• I've found that taking MCT on its own will often produce digestive problems, including nausea and apocalyptic diarrhea. Mixing MCT with other foods can reduce the problems, and I take MCT with cream or other foods.
• I found that MCT in larger doses (3+ tablespoons) can produce obvious thermogenesis, resulting in the perception that a cold room is actually overly warm. There is also a sensation of warmth radiating from my stomach, rather like I'd just consumed strong alcohol.
• There seem to be changes in mental functioning, especially with larger doses. MCT can alleviate some feelings of tiredness and improve mental acuity, but it can also result in an unpleasant feeling that is hard to describe. The sensation is a little like how I feel when a migraine is imminent.
• I've found that MCT taken during exercise seems to impair my running. I performed a simplistic experiment with MCT during a run to try to evaluate the effect.
  • At the time of the experiment I was adapted to the [[Ketogenic Diet], having blood ketones above 1.0 for the previous 10 days.
  • I started the run fasted, with my last dose of MCT at 2 PM the previous day.
  • For the first 8 miles, I felt really good, with my heart rate and breathing where I'd expect them to be.
  • At 8 miles I took 3 tbsp. of MCT with 2 tbsp. of Nutella.
  • By mile 10 my breathing had become strained, and I had to slow up slightly to keep things under control. My heart rate was slightly higher, but not enough to explain the breathlessness. My breathing problem peaked at about mile 11, before gradually easing off, though it never returned to normal.
  • At mile 19 I stopped for a drink and my blood pressure dropped dramatically. Even crouched down with my head between my knees I was dizzy. After a few minutes things returned to some semblance of normality and I was eventually able to stand up and continued to run.
  • A few days later I repeated the test, but took 3 tbsp. of Macadamia Nut Oil with 2 tbsp. of Nutella at mile 8. My breathing remained normal and I had no other problems.

14 See Also

• The classifications and types of Low Carbohydrate Diet.
• An introduction to the Ketogenic Diet.
• My experiences with ultrarunning on the Ketogenic Diet
  • How the Ketogenic Diet can be used for the treatment and management of disease.
    • Using the Ketogenic Diets to mitigate and treat Epilepsy
    • How Ketogenic Diets might help with Cancer
    • A look at the possible mechanisms of action of the Ketogenic Diet
  • Health Risks of the Ketogenic Diet
    • Health Checks for the Ketogenic Diet
    • Supplements for the Ketogenic Diet
  • The time frame and changes that occur with Ketoadaptation
  • What are Ketones
    • How to measure Ketones
    • What ketone levels to aim for
  • The pros and cons of the Ketogenic Diet for athletes
    • The Science of Ketogenic Exercise
  • The Types of Ketogenic Diet
    • The "traditional" Ketogenic Diet based on the Ketogenic Ratio
      • The ways the Ketogenic Ratio can be calculated
        • The different definitions of Net Carbohydrates
    • Low Glycemic Index Treatment
    • MCT Diet
      • MCT
    • Modified Atkins Diet (M.A.D.)
• My Ketogenic Recipes
• Non-Ketogenic Low Carbohydrate Diets