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    You’ve been intermittent fasting and doing well, but maybe you’re curious about what more you could be doing. Maybe you should add a supplement or two, like MCT oil. You’ve heard some gym buddies talking about it, but you’re too smart to just jump into something because it sounds good; you want to do your research first. You especially want to know, does MCT oil break a fast? 

    Curious about adding MCT oil to your intermittent fasting game? We’re here to spill the beans on whether it plays nice with your fast or breaks the rules.

    If you’ve been around here for a while, you know we’ve got the expert information you need to tailor your fasting to your needs and preferences. If you haven’t been introduced to us, welcome! We usually recommend you start off by checking in with your medical provider about whether or not fasting is for you. However, if you fit into any of these categories, we recommend you avoid fasting altogether. 

    A person who

    • is pregnant, breastfeeding, or trying to conceive
    • has type 1 diabetes
    • is on prescription medications 
    • is under the age of 18 or 80 years or older 
    • is extremely active
    • has a body mass index (BMI) < 18.5
    • has an eating disorder or a history of one (or is at risk of developing one)

    If you don’t fit into any of these groups and have gotten the all clear from your doctor to start intermittent fasting, we recommend taking our SIMPLE quiz to find out more about how we can help you know what to eat during intermittent fasting and what you can drink while fasting, among many other tips and resources. 

    Now, let’s answer the question that brought you to our little corner of the world. Do intermittent fasting and MCT oil mix? 

    What is MCT oil? 

    MCT oils are medium-chain triglycerides, a type of dietary fat made up of medium-length chains of fatty acids.[1] They are naturally found in oils such as coconut and palm kernel oil and milk fat. Because they are medium-chain fatty acids, they are quickly broken down and easily absorbed in the body. 

    Nutritional value

    While MCT oil is a potent (nine calories per gram) and quick source of energy, it is deficient in many essential nutrients. 

    If you fast for ketosis, there is some evidence that suggests it may help your efforts by giving you the energy you may need without raising your blood sugar or triggering an increase in insulin levels.[2] 

    While possibly supporting how intermittent fasting and its effect on insulin resistance play a role in weight loss, its high caloric value can be counterintuitive if not taken with care. 

    Health benefits and possible drawbacks of using MCT oil while intermittent fasting

    Balancing act: MCT oil in your intermittent fasting routine may fill you up, curb cravings, and even give your brain a boost! Just watch the speed — too much, too fast, might leave your stomach doing somersaults.


    • Increased satiety — Taking MCT oil while fasting may help you feel full faster and longer, thereby reducing your overall caloric intake. 
    • Reduced appetite — Increased satiety may lead to decreased appetite, making longer fasting windows a little more bearable. 
    • Cognitive function — Because MCTs are a quick and easy source of energy for the brain, there has been some promising research in MCTs benefiting cognitive and mental health functions.[2] However, the research has been limited to animal studies so far, so further testing (especially in humans) is needed before anything can be determined conclusively. 
    • Blood sugar — MCTs are a quick energy source, much like carbohydrates, but they provide energy without increasing blood sugar as long as no carbohydrates are ingested.[3] This is possibly a good pairing for supporting intermittent fasting for blood sugar control.

    These possible health benefits are promising, but the research is limited. We always recommend you check in with your doctor before adding fasting or MCT oils to your routine.


    • Digestive issues — If too many MCTs are taken too quickly, they can cause an upset stomach.[4] If you’re not careful to include it in a balanced, fiber-rich diet, it can also lead to constipation. 

    Will MCT oil break a fast?

    There are a few different perspectives on what breaks a fast, but it all boils down to your motive for fasting.If you’re all about that ketosis life, high five! MCT oil can be your fasting sidekick. But, if you’re on a mission to keep it super truly fasted, be warned: anything with more than 10 calories, including MCT oil, will throw a wrench in your fasting game by breaking your fast. 

    Now, let’s talk about lipids — because, you know, health matters. The research on how MCT oils mess with our lipid levels is like looking for a needle in a haystack; it’s pretty scarce. So, if you’ve got a history of hyperlipidemia or heart issues, maybe approach MCT oil with caution. Have a heart-to-heart with your healthcare provider. They’ll help you figure out if MCT oil is the superhero or the villain in your fasting adventure. Stay savvy and keep that fasting vibe alive! 

    Tips on using MCT oil during a fast

    While we know there are different opinions on MCT oil and intermittent fasting, as well as to the question, “Will MCT oil break a fast?” our opinion is that it does, and the best time to take MCT oil when fasting is during your eating window. We also recommend you check in with your doctor before adding any supplements. When included in a diet that has a variety of health-promoting foods, MCT oil may be beneficial for intermittent fasting, but this is very dependent from person to person.