Who Should Not Consume MCT Oil? Understanding the Risks

October 23, 2025 •

4 min read

While celebrated for its quick energy-providing properties, MCT oil is not suitable for everyone, and certain health conditions warrant its avoidance. Understanding who should not consume MCT oil is critical to prevent potential adverse health effects and ensure safe dietary choices.

Quick Summary

This article explains which individuals should avoid or be cautious with MCT oil, detailing the potential risks associated with liver disease, diabetes, and digestive issues. It covers critical considerations for making informed decisions about supplementation.

Key Points

Liver Disease: Individuals with any form of liver disease, including fatty liver and cirrhosis, should not consume MCT oil as it can worsen liver function.
Diabetes Mellitus: People with diabetes, particularly type 1, should avoid MCT oil to prevent potentially dangerous increases in ketone production that could lead to ketoacidosis.
Digestive Issues: Those with sensitive digestive systems or conditions like IBS and IBD are prone to severe gastrointestinal side effects such as cramping and diarrhea.
Pregnancy and Breastfeeding: Due to a lack of sufficient research on its safety, MCT oil should be avoided by women who are pregnant or breastfeeding.
High Triglycerides: People with elevated blood triglyceride levels or heart disease should use caution, as MCT oil may increase these fat levels and potentially impact cardiovascular health.
Allergies: Individuals with allergies to coconut or palm oil should avoid MCT oil, as these are its primary source.
Start Small: For those without contraindications, starting with a low dose and increasing gradually is key to minimizing common digestive side effects.

Critical Contraindications: Who Should Avoid MCT Oil?

Medium-chain triglycerides, or MCTs, are a type of fat derived from coconut and palm kernel oils. Unlike long-chain triglycerides, MCTs are rapidly metabolized by the liver, providing a quick source of energy. However, this unique metabolic pathway also means that certain individuals should approach MCT oil with extreme caution or avoid it entirely. Ignoring these contraindications can lead to serious health complications.

1. Individuals with Liver Disease

One of the most significant contraindications for MCT oil is liver disease. The liver is the primary organ responsible for processing MCTs. For those with compromised liver function, such as from cirrhosis, hepatic steatosis (fatty liver), or advanced liver disease, MCT oil can impose additional strain. Excessive intake may worsen existing conditions and contribute to further hepatic damage or fat accumulation in the liver. Patients with portacaval shunts, a procedure for high blood pressure inside the liver, should also avoid MCT oil as it could increase the risk of neurological problems.

2. People with Diabetes, Especially Type 1

MCT oil promotes ketone production, which can be problematic for people with certain metabolic conditions. While some research explores MCT oil's potential for improving insulin sensitivity in type 2 diabetes, the risk of inducing diabetic ketoacidosis (a dangerous condition involving high ketone levels) means that those with diabetes, particularly type 1, should not use it without strict medical supervision. In general, all individuals with diabetes should consult a healthcare provider, as results on blood sugar effects are mixed and can vary significantly.

3. Those with Digestive Disorders

Rapid consumption of large quantities of MCT oil can cause gastrointestinal distress, even in healthy individuals. For those with pre-existing digestive disorders such as Crohn's disease, irritable bowel syndrome (IBS), or inflammatory bowel disease (IBD), the side effects can be more pronounced. Symptoms may include diarrhea, cramping, gas, bloating, and nausea. Starting with very small doses and gradually increasing is sometimes advised, but many with sensitive digestive systems find MCT oil intolerable. Patients with pancreatic insufficiency, short bowel syndrome, or those who have undergone certain types of weight loss surgery should also be very cautious.

4. Individuals with High Triglycerides or Heart Disease

Despite its saturated fat content, MCT oil's effect on cholesterol and triglyceride levels is complex and not fully understood. Some studies suggest MCTs may increase both 'good' HDL and 'bad' LDL cholesterol, while others indicate they may slightly raise overall blood triglycerides. For individuals with a history of heart disease, hyperlipidemia, or those already managing high triglycerides, adding a concentrated source of saturated fat like MCT oil could be a risk. A healthcare provider's consultation is essential.

5. Women Who Are Pregnant or Breastfeeding

There is a significant lack of research and reliable information regarding the safety of MCT oil for pregnant or breastfeeding women. Due to the absence of sufficient safety studies, it is best to err on the side of caution and avoid its use during these sensitive periods.

6. People with Coconut or Palm Oil Allergies

Since MCT oil is primarily derived from coconut and palm kernel oil, individuals with allergies or sensitivities to these source ingredients should steer clear of MCT oil to prevent allergic reactions.

Comparison Table: MCT Oil Usage Considerations


Feature	Healthy Individuals	Individuals with Contraindications
Energy Source	Rapidly converted to ketones; used for quick energy, especially on a keto diet.	Metabolic processing may be impaired; potentially leading to complications like ketoacidosis in diabetics.
Liver Function	Processed efficiently by a healthy liver with moderate use.	Puts additional strain on a compromised liver; risk of exacerbating conditions or hepatic fat accumulation.
Digestion	Generally well-tolerated in small to moderate doses; can cause transient GI issues if started too quickly.	High risk of severe gastrointestinal distress, including diarrhea, cramping, and bloating.
Metabolic Health	Can support ketosis and potentially improve insulin sensitivity in some.	Potential for dangerous ketone buildup; can interfere with careful management of blood sugar.
Overall Safety	Considered generally safe when used in moderation within a balanced diet.	High risk of adverse effects; should be avoided or used only under strict medical supervision.

Potential Side Effects and Management

For those who do not have a hard contraindication but still experience issues, side effects are typically dose-dependent and related to the rapid absorption of MCTs. Common issues include stomach pain, gas, cramping, nausea, vomiting, and diarrhea. To mitigate these effects, it is recommended to start with a very small dose (e.g., 1 teaspoon) and increase gradually over time as tolerance builds. Taking MCT oil with food can also help minimize digestive upset. If side effects are persistent or severe, it is best to discontinue use and consult a doctor.

Conclusion: Prioritize Safety and Medical Advice

MCT oil has gained popularity for its purported benefits, but it is far from a universally safe supplement. A significant portion of the population, including those with liver disease, uncontrolled diabetes, certain digestive disorders, high triglycerides, and pregnant or breastfeeding women, should avoid or use MCT oil with extreme caution. The unique way MCTs are processed in the body means they can interfere with existing health conditions, causing serious side effects. Always prioritize your health by seeking professional medical advice from a doctor or registered dietitian before adding MCT oil to your routine, especially if you have pre-existing medical conditions. Moderation, careful monitoring, and a full understanding of the risks are key to safe supplementation.

For more information on the processing of dietary fats, consult an authority like WebMD.(https://www.webmd.com/vitamins/ai/ingredientmono-915/medium-chain-triglycerides-mcts)

Frequently Asked Questions

While a healthy liver can process MCT oil in moderation, long-term, high-dose consumption may lead to fat accumulation in the liver. Individuals with pre-existing liver conditions are at much higher risk and should avoid it.

MCT oil is not recommended for diabetics, especially those with type 1, due to the risk of increasing ketone levels and causing ketoacidosis. Those with type 2 diabetes should consult a doctor, as effects on insulin sensitivity are mixed.

Common digestive issues include diarrhea, gas, bloating, stomach pain, and cramping. These side effects are more likely with higher doses and for individuals with pre-existing digestive disorders.

There is a lack of reliable safety information regarding MCT oil's effects during pregnancy and breastfeeding. Until more research is conducted, health professionals advise staying on the safe side and avoiding it.

If you have any liver condition, such as cirrhosis or fatty liver disease, you should avoid MCT oil. Always consult with a healthcare provider before use, as they can assess your specific liver health.

Yes, alternatives include a balanced diet rich in healthy fats from sources like avocados, nuts, seeds, and olive oil, which can provide similar benefits without the concentrated effect of MCTs.

For those without contraindications, it is generally recommended to start with a very small dose, such as one teaspoon per day, and gradually increase it to assess your body's tolerance.