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What are the side effects of bulletproof MCT oil?


Bulletproof MCT oil has become a popular supplement among keto and paleo dieters. It’s marketed as a high-quality source of medium-chain triglycerides (MCTs), a type of saturated fat that has been linked to various health benefits. However, like any supplement, bulletproof MCT oil may cause side effects in some people. This article explores the potential side effects of bulletproof MCT oil and provides tips on how to minimize them.

What is Bulletproof MCT Oil?

Bulletproof MCT oil is a concentrated source of two specific MCTs: caprylic acid (C8) and capric acid (C10). It contains roughly 60% C8 and 40% C10. These MCTs are thought to be more rapidly absorbed and bioavailable than longer-chain fats.

Bulletproof markets their MCT oil as a high-performance brain fuel. They claim it can increase mental clarity, focus, and energy levels. The idea is that MCTs are efficiently converted into ketones, which act as an alternative fuel source for the brain.

Potential Side Effects of Bulletproof MCT Oil

Gastrointestinal Distress

The most common side effect of bulletproof MCT oil is gastrointestinal upset. Diarrhea, cramping, bloating, gas and nausea have all been reported.

This is because MCTs have a high osmotic effect in the gut. Their presence draws water into the intestines, which can cause loose stools or diarrhea. MCTs are also rapidly absorbed and metabolized, meaning they can act as a laxative if large amounts are consumed at once.

Those new to MCT oil are advised to start with small doses (1 teaspoon) and increase slowly over several weeks. This allows the body time to adapt. Taking MCT oil with food may also help minimize GI side effects. Slowly ramping up intake gives your gut time to adjust to the increased osmotic load.

Fatigue/Lethargy

Some people report feeling tired or sluggish after taking bulletproof MCT oil, especially when starting with high doses.

This fatigue may stem from low blood sugar. MCTs are quickly converted into ketones, which can accelerate carbohydrate metabolism. This may result in hypoglycemia if bulletproof oil is consumed before a meal.

Starting with small doses and using MCTs to replace other fats may help minimize the risk of fatigue and blood sugar crashes.

Allergic Reactions

As with any food product, allergic reactions are possible with bulletproof MCT oil. MCT oil is derived from coconut or palm oil, so those with nut allergies should use caution.

Allergic reactions may include rash, itching, swelling, dizziness, trouble breathing, or anaphylaxis. Those with known allergies should avoid bulletproof MCT oil.

Exacerbation of Liver Conditions

There is some concern that consuming large amounts of MCT oil may exacerbate underlying liver conditions like non-alcoholic fatty liver disease (NAFLD).

One small study found that mice fed a diet high in MCTs developed worse NAFLD than mice fed other types of fat. More research is needed, but those with liver issues should exercise caution with high intakes of MCT oil.

Increased Free Radical Damage

Some research indicates that large intakes of MCTs may increase oxidative stress by generating more free radicals. This could potentially accelerate aging and disease processes. However, the evidence is mixed.

One rat study found that large oral doses of MCTs increased liver and heart damage caused by free radicals. But other research indicates MCTs may have antioxidant effects inside cells. More studies are needed on the oxidative effects of MCT intake in humans.

Negative Interactions With Medical Conditions

Diabetes

MCT oil can lower blood sugar levels. Those with diabetes or hypoglycemia should monitor blood sugar closely when starting to use bulletproof MCT oil. Medication dosage may need to be adjusted.

Gallbladder Disease

MCTs are absorbed directly into the bloodstream and do not require bile from the gallbladder. However, some experts recommend those without a gallbladder start slowly with MCT oil and monitor for adverse effects.

Gastrointestinal Disorders

Due to their rapid absorption, MCTs can exacerbate diarrhea and other GI conditions. Those with IBS, short bowel syndrome, ulcerative colitis, or Crohn’s disease may want to avoid MCT oil.

Metabolic Syndrome

MCT oil is high in saturated fat. Those with metabolic syndrome, high cholesterol, or heart disease should exercise caution and speak to a doctor before use.

On Blood Thinner Medications

MCTs appear to have natural blood thinning effects. Patients on blood thinners like Coumadin should consult their doctor before using MCT oil.

Severity Can Vary by Individual

The severity of side effects can vary dramatically by individual. Factors like genetics, gut health, and dietary composition play a role.

Some people experience no side effects from bulletproof MCT oil. Others have significant gastrointestinal distress and must discontinue use. Starting slowly can help assess tolerance.

Tips to Minimize Side Effects

Here are some tips to help minimize potential side effects from bulletproof MCT oil:

– Start with very small doses (1 teaspoon) and increase slowly over 2-4 weeks. This allows time to assess tolerance.

– Take MCT oil with food, rather than on an empty stomach, to help decrease GI side effects.

– Mix oil into hot coffee or tea to help emulsify it prior to ingestion.

– Reduce intake of other high fat foods when first introducing MCT oil.

– Remain well hydrated to deal with the osmotic effect of MCTs.

– Avoid taking MCT oil before exercise or times of exertion to circumvent fatigue.

– Speak with a doctor before use if you have liver issues, diabetes, high cholesterol, or other medical conditions.

– Monitor blood sugar closely if diabetic or hypoglycemic.

– Discontinue use if severe nausea, diarrhea, fatigue or other unpleasant effects occur.

How Much Can You Tolerate?

Due to the potential for GI distress, it’s recommended to start with 1 teaspoon (5 ml) of bulletproof MCT oil and observe effects for a day or two before increasing the dosage.

If no significant side effects occur, the dose can be gradually increased to 2-3 teaspoons per day. Taking up to 4-5 tablespoons (60-75 ml) per day is considered a high but still safe dose for most people.

However, there is huge variability in individual tolerance. Some experience no ill effects at 3-4 tablespoons a day. Others get significant diarrhea and abdominal pain from just 1-2 teaspoons.

Listening to your body and increasing slowly is crucial to finding your personal maximum tolerated dose. Potential benefits also must be weighed against side effects.

Should You Use Bulletproof MCT Oil?

MCT oil can be a useful addition to the diets of certain populations. These include:

– Those following very low carb, ketogenic diets
– Individuals seeking improved mental clarity and focus
– People looking to increase satiety between meals
– Endurance athletes using MCT oil for energy

However, there are also plenty of potential drawbacks:

– GI distress is very common, especially when starting out
– Possible fatigue, lethargy, and low blood sugar
– Unknown long-term impacts at high intakes
– Lack of large, high-quality human studies on benefits
– No proven benefits for general population

As with any supplement, pros and cons of bulletproof MCT oil should be carefully weighed. Usage and dosage should be tailored to the individual.

Some people do best limiting MCT oil to occasional use, while others are able to use it daily with no adverse effects. Working with a healthcare practitioner knowledgeable about ketogenic diets can help determine if MCT oil is appropriate for your individual needs and goals.

The Bottom Line

Bulletproof MCT oil provides a concentrated source of C8 and C10 MCTs. But like many supplements, it may cause side effects in some individuals.

The most common side effect is GI distress, including diarrhea, cramping, and nausea. Fatigue, allergic reactions, and dangerously low blood sugar are also possible.

Those with liver issues, gallbladder disease, diabetes, or gastrointestinal disorders should exercise particular caution with bulletproof MCT oil.

When starting out, begin with small doses like 1 teaspoon per day. Slowly work up to assess personal tolerance. Consider decreasing intake of other fats when introducing MCT oil.

While bulletproof MCT oil is unlikely to cause serious harm in healthy people at reasonable doses, side effects can range from mild to quite uncomfortable. Using the smallest effective dose and monitoring effects carefully is key to getting any benefits while avoiding unwanted outcomes.

If significant adverse effects occur, cease usage. As with any supplement, consult your doctor before adding bulletproof MCT oil, especially if you have any medical conditions or take medications.

Frequently Asked Questions

Is it ok to cook with MCT oil?

Yes, MCT oil has a high smoke point of 320°F (160°C) so it can be safely used for cooking. However, some people prefer to consume it straight or add it to foods after cooking for maximum ketone-boosting effect.

What happens if you consume too much MCT oil?

Consuming more MCT oil than your body can tolerate may lead to diarrhea, nausea, vomiting, and cramping. Overuse over time could potentially lead to fat buildup in the liver. Stick within recommended dosage guidelines and monitor your response.

Can MCT oil be used during intermittent fasting?

Yes, you can consume MCT oil during fasting periods. MCTs produce ketones, which can help maintain energy levels and cognitive function while fasting. The calories in MCT oil may technically break your fast but won’t significantly impact fat burning.

Is MCT oil better than coconut oil?

MCT oils contain a higher concentration of caprylic and capric fatty acids than coconut oil. Therefore, they may be more rapidly absorbed and more efficiently converted to ketones. However, coconut oil provides other beneficial nutrients like lauric acid.

Can you cook with bulletproof MCT oil?

Yes, bulletproof MCT oil has a high smoke point so it is suitable for cooking. However, some of the volatile C8 and C10 fats may degrade from heat exposure. You may get more benefit from using bulletproof oil unheated.