Does MCT Oil Raise ApoB? A Deep Dive into the Research

November 30, 2025 •

4 min read

According to a 2014 study published in the American Journal of Clinical Nutrition, a four-week regimen of MCT oil had no significant effect on apolipoprotein B-48 or B-100 kinetics in insulin-resistant men when compared to corn oil. This finding challenges assumptions and requires a closer look at the complex relationship between MCT oil and ApoB.

Quick Summary

The impact of MCT oil on apolipoprotein B levels is not straightforward, with research indicating it may be neutral or dependent on the type of fats it replaces in the diet. The broader dietary context, such as a ketogenic diet, is often a more significant factor influencing ApoB than the MCT oil itself.

Key Points

Neutral Effect in Specific Studies: A 2014 randomized trial found no significant effect of 20g/day MCT oil for four weeks on ApoB-48 and ApoB-100 kinetics in insulin-resistant men compared to corn oil.
Context Matters: The effect of MCT oil on lipids can depend on what fat it replaces; it may raise LDL when replacing unsaturated fats but may not when compared to long-chain saturated fats.
Metabolic Pathway Differences: MCTs are metabolized differently than LCTs, being rapidly absorbed and oxidized for energy rather than being heavily incorporated into ApoB-containing lipoproteins like LDL.
Overall Diet Impact: The ketogenic diet, which often utilizes MCT oil, is associated with increased ApoB levels due to its overall high-fat, low-carb nature, not the MCT oil alone.
Increased Triglycerides: Some meta-analyses have found that while MCT oil doesn't significantly affect LDL or HDL cholesterol, it can cause a small increase in fasting triglycerides.
Considerations for High-Risk Groups: Individuals with metabolic syndrome, diabetes, or specific genetic variants (like APOE4) may experience different and potentially exaggerated ApoB responses to a high-fat diet containing MCT oil.

What is ApoB and Why Does it Matter?

Apolipoprotein B (ApoB) is a crucial protein found on the surface of all atherogenic lipoprotein particles, including very-low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL), and low-density lipoprotein (LDL). Because there is one ApoB molecule per particle, measuring ApoB provides a direct count of the number of these potentially harmful particles in the bloodstream. Elevated levels of ApoB are a strong indicator of increased cardiovascular risk, particularly in individuals with metabolic syndrome or high triglycerides, where ApoB reflects the number of small, dense LDL particles.

The Short-Term Research on MCT Oil and ApoB

A 2014 double-blind randomized crossover trial examined the effects of MCT oil on ApoB kinetics. Twenty-eight obese, insulin-resistant men received either 20 grams of MCT oil or 20 grams of corn oil daily for four weeks. The study found no significant effect of MCT oil on plasma lipoprotein profiles, ApoB-48 kinetics, or ApoB-100 kinetics when compared to the corn oil control. This suggests a neutral effect on the metabolism of these key lipoproteins over the short term in this population.

The Conflicting Evidence: Role of Comparison Fats

While the specific ApoB kinetics study showed a neutral effect, other research indicates that MCT oil's impact on cholesterol and ApoB can vary depending on what dietary fats it replaces. A 2021 systematic review and meta-analysis highlighted this complexity. Replacing primarily unsaturated fatty acids with MCT oil tended to increase total and LDL cholesterol. However, when MCT oil replaced longer-chain saturated fatty acids, there was weak evidence of lower LDL cholesterol. This difference arises because unsaturated fats generally have more beneficial effects on blood lipids than saturated fats.

MCT Oil vs. Long-Chain Triglycerides (LCTs) on Lipids


Feature	MCT Oil (Medium-Chain Triglycerides)	LCTs (Long-Chain Triglycerides)	Effect on Lipoproteins (Relative)
Absorption	Absorbed directly into the portal vein, bypassing the lymphatic system.	Absorbed into the lymphatic system via chylomicrons.	Neutral to LDL/ApoB (compared to corn oil). May have complex effects depending on the comparator fat.
Metabolism	Rapidly oxidized for energy in the liver, leading to ketone production.	More likely to be stored as fat or incorporated into triglycerides.	Increased VLDL (in some comparisons), possibly from increased hepatic TG production.
Effect on LDL/ApoB	Can be neutral, but may increase LDL if replacing unsaturated fats.	Directly incorporated into chylomicrons and subsequently into VLDL/LDL pathways.	Directly influences ApoB-containing lipoproteins.
Fasting Triglycerides	May cause a small increase in triglycerides compared to other oils.	Effects depend on type of LCT (saturated vs. unsaturated).	MCTs may slightly elevate fasting triglycerides.

The Broader Context: MCT Oil and the Ketogenic Diet

The effects of MCT oil should be considered within the context of the overall diet. Many individuals use MCT oil as part of a ketogenic diet to boost ketone production. Research indicates that high-fat, low-carbohydrate ketogenic diets can lead to increases in cholesterol and ApoB levels. This rise in ApoB is often attributed to the dietary composition of the ketogenic diet itself, rather than solely the MCT oil. Genetic factors, such as the APOE3/4 variant, can also influence the magnitude of LDL and ApoB elevation on a ketogenic diet. Therefore, attributing an increase in ApoB solely to MCT oil in this context is likely an oversimplification; the overall diet and individual metabolic response are key factors.

The Mechanisms Behind MCT's Neutral Effect

The unique metabolic pathway of medium-chain fatty acids (MCFAs) from MCT oil contributes to its often neutral effect on ApoB. Unlike long-chain triglycerides (LCTs), which are absorbed into the lymphatic system via chylomicrons, MCFAs are rapidly absorbed and transported directly to the liver through the portal vein. This allows MCFAs to be quickly used for energy or converted into ketones, with less being incorporated into VLDL and subsequently LDL particles, which are the primary carriers of ApoB. This distinct processing helps explain why some studies observe a neutral effect on ApoB-100 kinetics with MCT oil supplementation.

Conclusion

The question of whether MCT oil raises ApoB is nuanced and depends significantly on the dietary context. A specific short-term study on insulin-resistant men found no significant effect of MCT oil on ApoB kinetics compared to corn oil. However, broader research suggests that the type of fat MCT oil replaces in the diet is crucial; substituting healthier unsaturated fats with MCT oil may result in a less favorable lipid profile. Furthermore, the association between ketogenic diets and elevated ApoB is linked to the overall high-fat dietary pattern, not just the MCT oil component. For most individuals, moderate MCT supplementation within a balanced diet is unlikely to cause negative effects on ApoB. However, those with metabolic syndrome, diabetes, or certain genetic predispositions may experience more pronounced changes and should consult a healthcare professional. For more information on the significance of ApoB for heart health, resources from the American Heart Association are available.

Optional outbound link: American Heart Association: The Importance of Apo B and Lipoprotein Little a [Lp(a)]

Frequently Asked Questions

Yes, MCT oil can influence cholesterol, but the effect varies. Studies suggest it might increase LDL cholesterol when replacing unsaturated fats, but may be more neutral or beneficial compared to long-chain saturated fats. Overall, meta-analyses suggest no meaningful effect on LDL or HDL cholesterol, but a small increase in triglycerides.

The ketogenic diet as a whole, rather than just the MCT oil, is associated with increased ApoB levels. While MCT oil helps produce ketones, the diet's high-fat nature is the primary driver of lipid changes, and individual metabolic responses can be significant.

Some evidence suggests ApoB can be a superior predictor of cardiovascular risk, especially in individuals with metabolic syndrome, diabetes, or high triglycerides. This is because ApoB measures the total number of atherogenic particles, reflecting risk more comprehensively than just LDL cholesterol.

MCTs are absorbed directly into the portal vein and go straight to the liver for quick energy. LCTs, in contrast, are packaged into chylomicrons and transported via the lymphatic system, a pathway more directly involved in the formation of ApoB-containing lipoproteins.

For most healthy individuals, moderate long-term use of MCT oil is considered safe. However, those with pre-existing cardiovascular concerns, metabolic syndrome, or diabetes should monitor their lipid profiles and discuss supplementation with a healthcare professional due to the potential for complex and individualized lipid responses.

The 2014 study that found a neutral effect on ApoB kinetics used a dose of 20 grams of MCT oil per day. This is a moderate amount and consistent with general recommendations.

Yes, some meta-analyses have found that MCT oil consumption can lead to a small but statistically significant increase in fasting triglycerides compared to other oils. This might be linked to MCFA-induced de novo lipogenesis.