Does MCT oil break a fast?

If you’re adding intermittent fasting as part of your ketogenic lifestyle, you might be concerned and wonder if adding MCT oil break a fast.

Let’s look at the basics of MCT oil and if adding MCT oil to your coffee in the morning would break your intermittent fast.

What is MCT Oil?

MCT oil stands for medium-chain triglycerides, which is a type of fat. MCT oils or fatty acids have between 6 and 12 carbon atoms. Short chain triglycerides had less than six carbon atoms and long chain triglycerides have 13 or more carbon atoms.

Triglycerides contain three fatty acids attached to a glycerol backbone and can be broken down by the body to release the individual fatty acids. You’ll often hear the terms “MCT oil,” medium-chain triglycerides,” and “medium-chain fatty acids” used interchangeably. They all refer to the same MCT molecule.

Because of the chemical structure of these types of fatty acids, they are also considered saturated fats or fatty acids because all carbon atoms have single bonds to the next carbon atom. Fat molecules that have chemical double bond between two carbon atoms due to the lose of a hydrogen atom are called “unsaturated” fats or fatty acids because of the missing hydrogen atom.

If the fat molecule is only missing one hydrogen atom (and has one carbon double bond) its a “monounsaturated” fatty acid or MUFA. If the fat molecule is missing two or more hydrogen atoms and has two or more carbon double bonds, its called a polyunsaturated fatty acid or PUFA.

The most common MCTs are:

• Caproic (hexanoic) acid – 6 carbon fatty acid
• Caprylic (octanoic) acid – 8 carbon fatty acid
• Capric (decanoic) acid – 10 carbon fatty acid
• Lauric (dodecanoic) acid- 12 carbon fatty acid

Most nutritional experts will lump caproic, caprylic and capris acid under the MCT label and exclude lauric acid because lauric acid does not seem to have the same health benefits as the other three medium-chain fatty acids. However, all the MCTs appear to be metabolized quickly by the body and are not stored in adipose (fat) tissue in the same way that long-chain fatty acids are. ¹

Most MCT oils are derived from either coconut or palm kernel oils that have been refined to remove the long-chain triglycerides, leaving only the medium-chain triglycerides.

Read more about the benefits of MCT oil here.

What’s the difference between MCT and coconut oil?

Coconut oil contains a mixture of medium and long-chain fatty acids as well as unsaturated fats. The MCT concentration of coconut oil is about 40% lauric acid (C12) , 7% caprylic acid (C8) , and 5% capric acid (C10) ² while most MCT oils are a combination of just caprylic (C8) and capric (C10) fatty acids.

Does MCT oil raise blood glucose?

MCT oil does not raise blood sugar. The medium-chain triglycerides of caprylic (C8) and capris (C10) fatty acids are produced by the liver and converted to ketone bodies. These ketones are then taken up by the cells and used by the mitochondria for a fuel source. So MCT oil has no impact on blood glucose levels. Since blood glucose levels don’t increase, MCT oil won’t break your fast.

What are the benefits of MCT oil during a fast?

Using MCT oil during your fast can give you several benefits that include:

• Getting you into ketosis quicker
• Improving insulin sensitivity ³
• Improve exercise performance versus strict water fast ^{4 5}
• Improved cognition and brain function ⁶

MCT Oil for quicker ketosis

Medium-chain triglycerides are absorbed from the gut and go directly to the liver. Once the MCTs reach the liver, they are converted to ketones and then released back into the blood stream. Caprylic acid (C8) appears to raise blood ketone levels higher than capris acid (C10) ⁷

MCT oil may suppress hunger

Another benefit of adding MCT oil to your coffee or other drink while fasting is that MCT oil may also decrease hunger more than coconut oil ⁸

MCT oil may help with weight loss

Many people are adopting the ketogenic diet and intermittent or longer fasting not only for the health benefits of improved insulin sensitivity but also to lose weight. There are studies that demonstrate that adding MCT oil to your diet can help with weight loss. ⁹” class=”rank-math-link”>https://pubmed.ncbi.nlm.nih.gov/17570262/)) One study found that supplementing with medium-chain triglycerides led to greater weight loss than supplementing with olive oil ¹⁰, which is higher in long-chain fatty acids and lower in medium-chain fatty acids

MCT oil will not break your fast especially in the small amounts used when added to coffee. In fact, adding a couple of tablespoons of MCT oil may boost your ketone levels during your fasting and get your body deep into a state of autophagy.

1. https://openheart.bmj.com/content/3/2/e000467[↩]
2. https://tools.myfooddata.com/nutrition-facts.php?food=171412&serv=wt1&qty=1[↩]
3. https://pubmed.ncbi.nlm.nih.gov/17570262/[↩]
4. https://pubmed.ncbi.nlm.nih.gov/29420554/[↩]
5. https://pubmed.ncbi.nlm.nih.gov/19436137/[↩]
6. https://pubmed.ncbi.nlm.nih.gov/31694759/[↩]
7. https://www.frontiersin.org/articles/10.3389/fnut.2019.00046/full[↩]
8. https://www.sciencedirect.com/science/article/abs/pii/S0031938417302111[↩]
9. [↩]
10. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2874190/[↩]