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Fatty Acid Supplement

MCT Oil — Research Profile

Evidence:Moderate
·

This content is for informational purposes only and does not constitute medical advice. Statements about dietary supplements have not been evaluated by the FDA and are not intended to diagnose, treat, cure, or prevent any disease. Individual results may vary — consult your healthcare provider before starting any supplement. Full disclaimer

MCT oil can raise ketones.

MCT oil can raise ketones. Replacing long-chain fats with MCTs produced about 0.51 kg more weight loss in a 13-trial meta-analysis, but adding oil adds calories. Dementia research is preliminary, and the cited studies do not establish an endurance benefit or guaranteed mental clarity.

MCTs can raise ketones and modestly affect weight when replacing other fats. Cognitive benefit remains uncertain; extra oil still adds calories and can cause gastrointestinal symptoms.

Evidence:Meta-analysis (2015) · 13 RCTs · n=749 · moderate confidence[#1]. See full reference list below.

Key Facts

What it is
Medium-chain triglycerides (C6-C12 fatty acids) extracted from coconut or palm kernel oil, rapidly converted to ketones in the liver
Primary benefits
  • Ketone production varies by preparation and meal
  • Small average weight change when replacing other fats
  • Preliminary cognition research; no established endurance benefit
Typical dosage
15-30ml (1-2 tablespoons) daily
Evidence level
Moderate
Safety profile
Generally Safe

Time to Effect

Hours
Days
Weeks
Months
15-30 minutestypical onset

Ketone production begins within 15-30 minutes of ingestion, peaking at 1-2 hours. Appetite suppression effects are acute. Cognitive benefits in MCI/Alzheimer's patients require 1-3 months of daily use. Weight management effects accumulate over 4-12 weeks.

What the Research Says

A 2015 meta-analysis of 13 trials involving 749 adults found that replacing long-chain triglycerides with MCTs reduced weight by an average of 0.51 kg. Trial quality, commercial bias and differences in dose and energy control limit certainty. This does not establish a 250 kcal/day reduction in food intake or justify adding oil without accounting for calories.

C8 produced higher ketone responses than other oils in a nine-person acute study. Ketones are an alternative fuel, but a higher blood level is not proof of improved mental clarity or endurance. The 20-patient Alzheimer formula study found no acute cognitive advantage versus placebo; its later 12-week findings were uncontrolled and compared with baseline.

MCT preparations and populations vary. The cited review does not support an exercise-performance benefit. Omega-3 studies in dialysis or preterm infants are different interventions and do not establish MCT efficacy.

Benefits of MCT Oil

  • Ketones — a nine-person acute crossover study found C8 more ketogenic than other tested oils. This biomarker result does not prove better cognition or performance.
  • Weight — 13 trials involving 749 adults found a mean difference of −0.51 kg versus long-chain fats. This concerns replacement, not simply adding oil to the usual diet.
  • Cognition — a 20-patient Alzheimer study found no acute cognitive difference versus placebo. Its subsequent 12-week phase was uncontrolled and had 16 completers, so improvements versus baseline cannot establish treatment efficacy.
  • Exercise and infection claims — the cited evidence does not establish an 8–12% endurance improvement or oral treatment of Candida. Laboratory antimicrobial activity is not a clinical gut-health outcome.

Our Top MCT Oil Picks

As an Amazon Associate, we earn from qualifying purchases. Some links below are affiliate links — this doesn't affect our editorial independence or product ratings. How we evaluate products

Bulletproof Brain Octane C8 MCT Oil
Bulletproof Brain Octane C8 MCT Oil
Bulletproof
#1 Top Pick
OverallForm: LiquidPrice: $29.99 · $1.87 / fluid ounce
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Garden of Life Dr. Formulated Brain Health Organic MCT Oil
Garden of Life Dr. Formulated Brain Health Organic MCT Oil
Garden of Life
Best for BrainForm: LiquidPrice: $18.19 · $1.14 / fluid ounce
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Sports Research MCT Oil Capsules 3000mg Coconut Softgels
Sports Research MCT Oil Capsules 3000mg Coconut Softgels
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See all mct oil products →
Did you know?

A 2015 meta-analysis of 13 trials involving 749 adults found that replacing long-chain triglycerides with MCTs reduced weight by an average of 0.51 kg.

Forms of MCT Oil

MCT Oil supplement forms compared by bioavailability and best use
FormBioavailabilityBest For
C8 (Caprylic Acid) OilVery HighLarger ketone response in a small acute comparison; clinical superiority unproven
C8 + C10 BlendHighMixed medium-chain fat preparation; results depend on composition and dose
MCT PowderHighConvenient format; carrier ingredients and tolerance vary
Liquid MCT Oil (Full Spectrum)ModerateBudget option — contains C8, C10, and C12 (lauric acid); less ketogenic than pure C8

Dosage Recommendations

General recommendation: No universal effective dose for weight loss or cognition. Studies use different oils and quantities; account for energy intake and gastrointestinal tolerance.

Timing: No validated pre-meal or pre-workout schedule for clinical benefit. Taking large amounts at once often worsens tolerance.

Dosage by Condition

Weight management
No established dose; evidence concerns replacing other fatsEmerging
Cognitive disorders
Experimental preparations; discuss with the treating clinicianPreliminary
Exercise endurance
No established beneficial regimenPreliminary

Upper limit: No established safe upper limit. Gastrointestinal intolerance depends on amount, product and individual.

Medication Interactions & Contraindications

Drug Interactions

diabetes-medication
moderate
diabetes-medication
MCT oil promotes ketone production and can alter glucose-ketone dynamics. In insulin-dependent diabetics, rapid ketone elevation without dose adjustment may increase ketoacidosis risk; closer glucose and ketone monitoring is warranted.
orlistat
minor
orlistat
Orlistat inhibits fat absorption, which may reduce MCT oil's effectiveness and worsen GI side effects (oily stools, urgency). Separate dosing by at least 2 hours.

Who Should NOT Take This

Type 1 Diabetes(relative)
MCT oil rapidly elevates blood ketone levels. In type 1 diabetics, this may contribute to diabetic ketoacidosis (DKA) if insulin dosing is not carefully managed. Use only under medical supervision.
Severe Liver Disease(relative)
MCTs are metabolized primarily in the liver. Advanced liver disease or hepatic insufficiency may impair MCT metabolism, leading to accumulation. Consult a hepatologist before use.
Fat Malabsorption Disorders(relative)
While MCTs bypass bile-dependent digestion, individuals with severe fat malabsorption conditions (e.g., short bowel syndrome) may still experience significant GI distress. Start with very low doses under medical guidance.

This information is for educational purposes only. Always consult your healthcare provider before starting or stopping any supplement, especially if you take prescription medications.

Side Effects and Safety

Safety profile: Generally Safe

Potential Side Effects

  • GI distress (nausea, cramping, diarrhea) — very common when starting too fast; dose-dependent
  • Loose stools at higher doses, especially with C8-dominant products
  • Mild nausea when taken on a completely empty stomach
  • Rarely: elevated LDL cholesterol in some individuals with prolonged high-dose use

Drug & Supplement Interactions

  • May alter blood glucose and ketone levels — use caution with diabetes medications
  • High caloric density (115 kcal per tablespoon) may affect weight if not accounted for in total intake
  • No significant drug-drug interactions have been identified in clinical trials

Do not exceed: No established safe upper limit. Gastrointestinal intolerance depends on amount, product and individual.

Check MCT Oil interactions with other supplements →
BenefitsDosage GuideSide EffectsTypes & FormsResearchFAQ

Related Conditions

Energy & FatigueWeight LossCognitive FunctionGut Health & Digestion

Commonly Taken Together

+
Fish Oil
Both support general wellness
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Omega-3
Both support cognitive-function
See top omega-3 products →
+
Coconut Oil
Both support energy
See top coconut oil products →

Related Guides

Keto & Low-Carb Supplements Guide
Supplements that genuinely help on keto and low-carb diets — electrolytes, magnesium, potassium, fiber — to manage the 'keto flu' and common gaps, with honest framing on MCT and exogenous ketones.
Omega-3 & Healthy Fats Supplements Guide
How to choose among omega-3 and fat supplements — fish oil, krill, cod liver, flax, algae, MCT — by EPA/DHA content, conversion, and quality, with an oxidation caution.

Related Supplements

Fish OilStrong

Distinguish nutritional fish oil from prescription omega-3 treatment. Triglyceride lowering does not guarantee fewer cardiovascular events, and REDUCE-IT’s result cannot be assigned to every EPA/DHA product. [1,2,13]

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Omega-3Strong

Bottom line: Omega-3s have strong evidence for heart, brain, and joint health. Take 1,000-2,000mg EPA+DHA daily — choose triglyceride form fish oil or algal oil for vegans.

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Coconut OilEmerging

Coconut oil raises LDL compared with nontropical vegetable oils. Higher HDL does not establish cardiovascular benefit; concentrated-MCT studies do not establish equivalent coconut-oil effects. [1][5][10]

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Looking for the best mct oil supplement?

We analyzed and ranked the top products based on form, dosage, third-party testing, and value.

See Our Top Picks

Frequently Asked Questions

What is the difference between C8 and C10 MCT oil?

C8 and C10 are different fatty-acid chain lengths. A nine-person acute crossover study found a larger ketone response with C8 than the other tested oils, but this does not establish superior cognition, sustained energy or antimicrobial benefit. Ketone production and clinical benefit are separate outcomes.

Evidence:Study (2017)[#7]. See full reference list below.

Is MCT oil the same as coconut oil?

No. Coconut oil and purified MCT products have different fatty-acid mixtures. In a small acute study, coconut oil produced a lower peak ketone response than C8. The ratio depended on the protocol and should not be interpreted as a universal speed or efficacy ratio.

Evidence:Study (2017)[#7]. See full reference list below.

Why does MCT oil cause stomach problems?

Nausea, cramps and diarrhea are common, particularly with larger amounts. Smaller portions may be better tolerated, but no fixed titration schedule guarantees adaptation. Powder carriers and oil amounts vary, so a powder is not automatically gentler.

Evidence:Review (2010) · low confidence[#5]. See full reference list below.

Can MCT oil help with Alzheimer's or dementia?

The evidence remains preliminary. The cited 20-patient formula study showed no acute cognitive benefit versus placebo; its later 12-week phase was uncontrolled. MCT oil is not an established dementia treatment, and ketone increases alone do not prove a meaningful cognitive effect.

Evidence:RCT (2004) · n=20 · moderate confidence[#2]. See full reference list below.

Do I need to be on a keto diet for MCT oil to work?

MCTs can raise ketones without a strict ketogenic diet, but meal composition, oil type and dose affect the response. A fixed 0.3–0.5 mmol/L increase is not guaranteed, nor does a measurable increase prove a health benefit.

Evidence:Study (2013)[#6]. See full reference list below.

How many calories are in MCT oil?

MCT oil contains approximately 115 calories per tablespoon (15ml), which is slightly less than other oils (olive oil has ~120 kcal per tbsp). While MCTs are less likely to be stored as fat due to their rapid metabolism, the calories still count. If you are adding MCT oil to your diet for weight loss, you need to account for it in your total caloric intake.

When is the best time to take MCT oil?

No clinical evidence establishes a preferred morning, pre-meal or pre-workout schedule. Consider the total calories and tolerance rather than expecting a particular hour to improve mental clarity, appetite or endurance.

Evidence:Meta-analysis (2015) · 13 RCTs · n=749 · moderate confidence[#1]. See full reference list below.

Continue Reading

Condition Guide

Energy & Fatigue

The cited creatine, citrulline and beetroot research primarily concerns exercise performance, not treatment of chronic unexplained fatigue. A separate iron trial found reduced fatigue in nonanemic menstruating women with low ferritin. These findings support matching the intervention to the cause, rather than assuming that every energy supplement treats the same problem.

Product Comparison

Best MCT Oil Supplements

See our top ranked products

References

  1. Meta-analysisMumme K, Stonehouse W (2015). Effects of medium-chain triglycerides on weight loss and body composition: a meta-analysis of randomized controlled trials. Journal of the Academy of Nutrition and Dietetics. DOI PubMed
  2. RCTReger MA, Henderson ST, Hale C, Cholerton B, Baker LD, Watson GS, Hyde K, Chapman D, Craft S (2004). Effects of beta-hydroxybutyrate on cognition in memory-impaired adults. Neurobiol Aging. DOI PubMed
  3. RCTSt-Onge MP, Bosarge A (2008). Weight-loss diet that includes consumption of medium-chain triacylglycerol oil leads to a greater rate of weight and fat mass loss than does olive oil. American Journal of Clinical Nutrition. DOI PubMed
  4. RCTOta M, Matsuo J, Ishida I, Takano H, Yokoi Y, Hori H, Yoshida S, Ashida K, Nakamura K, Takahashi T, Kunugi H (2019). Effects of a medium-chain triglyceride-based ketogenic formula on cognitive function in patients with mild-to-moderate Alzheimer's disease. Neurosci Lett. DOI PubMed
  5. ReviewClegg ME (2010). Medium-chain triglycerides are advantageous in promoting weight loss although not beneficial to exercise performance. Int J Food Sci Nutr. DOI PubMed
  6. Courchesne-Loyer A, Fortier M, Tremblay-Mercier J, et al. (2013). Stimulation of mild, sustained ketonemia by medium-chain triacylglycerols in healthy humans: estimated potential contribution to brain energy metabolism. Nutrition. DOI PubMed
  7. Vandenberghe C, St-Pierre V, Pierotti T, Fortier M, Castellano CA, Cunnane SC (2017). Tricaprylin Alone Increases Plasma Ketone Response More Than Coconut Oil or Other Medium-Chain Triglycerides. Current Developments in Nutrition. DOI PubMed
Show 2 more references
  1. Tosefsky K, Lam JS, Wang YN, Keymanesh S, et al. (2026). A randomized safety and feasibility crossover trial of two Mediterranean-ketogenic interventions in individuals with Parkinson's disease.. Journal of Parkinson's disease. DOI PubMed
  2. Rasmussen E, Patel V, Tideman S, Frech R, et al. (2023). Efficacy of supplemental MCT oil on seizure reduction of adult drug-resistant epilepsy - a single-center open-label pilot study.. Nutritional neuroscience. DOI PubMed