Decanoic acid—also called capric acid or “C10” because it has 10 carbon atoms—is a medium-chain fatty acid found naturally in coconut and palm kernel oils and in small amounts in dairy fat. It is a key component of many medium-chain triglyceride (MCT) oils and several medical foods used in ketogenic therapies. Interest in decanoic acid has grown because it is metabolized quickly for energy, can raise circulating ketones, and, uniquely among dietary fats, appears to act directly on brain receptors involved in seizure activity. Beyond neurology, researchers are exploring its roles in cognition, metabolic support, and clinical nutrition. This guide explains what decanoic acid is, how it works, the most studied benefits, practical ways to use it, evidence-based dosage ranges, and safety considerations so you can make informed decisions with your healthcare professional.
Top Decanoic Acid Highlights
- Anti-seizure potential: C10 can directly dampen AMPA-type glutamate signaling in the brain and may reduce seizure frequency in some patients on ketogenic or C10-enriched regimens.
- Brain energy support: As part of MCTs, C10 is rapidly oxidized and can increase ketone availability, with emerging evidence for cognitive support in select groups.
- Suggested dose window: Start with 5–10 mL MCT oil once daily with food, titrating to 10–30 mL/day (≈1–2 tablespoons) in divided doses as tolerated.
- Safety note: Higher intakes often cause gastrointestinal upset (bloating, cramping, diarrhea); increase slowly and take with meals.
- Who should avoid without supervision: People with significant liver disease, known fatty-acid oxidation disorders, or on strict therapeutic ketogenic diets should only use under clinical guidance.
Table of Contents
- What is decanoic acid?
- Decanoic acid benefits
- How to use decanoic acid
- How much per day?
- Safety and side effects
- What the science says
What is decanoic acid?
Decanoic acid (capric acid, “C10:0”) is a saturated medium-chain fatty acid. Medium-chain fatty acids (MCFAs) are typically 6–12 carbons long and behave differently from the long-chain fats common in everyday foods. Once ingested, most C10 is absorbed quickly and transported directly to the liver via the portal vein. Unlike long-chain fats, MCFAs do not require bile salts for micelle formation or carnitine shuttles to enter mitochondria. That “shortcut” explains why MCT oils—blends rich in C8 (caprylic) and C10—can be rapidly converted into cellular energy and ketone bodies (beta-hydroxybutyrate and acetoacetate).
Chemically, decanoic acid is a straight 10-carbon saturated chain with a terminal carboxyl group. In supplements and clinical nutrition products, it is usually consumed as part of a triglyceride (an MCT), not as a free fatty acid. Common dietary sources include coconut oil and palm kernel oil, though those natural oils also contain longer-chain fats. Commercial MCT oils are typically fractionated to deliver primarily C8 and C10; some products and medical foods are enriched in C10 specifically.
What sets C10 apart is that, beyond serving as a fuel, it shows direct signaling effects in neural tissue. Laboratory work indicates that decanoic acid can reduce excitatory neurotransmission by acting as a non-competitive antagonist at AMPA-type glutamate receptors. In practical terms, this dampens one of the brain’s fast excitatory channels implicated in seizure propagation. This mechanism is independent of ketone levels—meaning C10 may contribute to seizure control even when ketosis is mild.
In the broader metabolic context, MCT-derived fatty acids like C10 are oxidized readily and may influence mitochondrial function, gene expression related to energy metabolism, and astrocyte–neuron coupling. Researchers are investigating whether these properties translate into measurable benefits for cognition, gait and muscle function in older adults, and clinical nutrition in malabsorptive states. However, the most mature evidence today centers on neurology and ketogenic dietary therapy, with clinical outcomes strongest in drug-resistant epilepsy programs where C10 is delivered as part of a structured regimen.
Finally, because MCTs lack essential fatty acids (linoleic and alpha-linolenic acids), decanoic-heavy regimens must still include sources of essential fats over the long term. That point matters for people using MCTs aggressively as calorie sources or on strict therapeutic diets.
Decanoic acid benefits
1) Seizure management within ketogenic therapy
The best-documented benefit of decanoic acid is its contribution to seizure reduction in ketogenic programs. Mechanistically, C10 directly inhibits AMPA receptors that mediate fast excitatory signaling, helping to stabilize neuronal activity. Clinical studies using C10-enriched approaches, including specialized medical foods and ketogenic diet variants, report meaningful seizure reductions in a subset of patients with refractory epilepsy. A recent pediatric crossover study comparing a classic ketogenic diet to a C10-enriched ketogenic diet found comparable—often improved—seizure control, with manageable adverse events. Feasibility work with a decanoic-rich medical food also showed reductions in seizure frequency despite minimal ketosis, aligning with the receptor-level mechanism.
2) Cognitive support in select populations
Because MCTs are rapidly metabolized to ketones—an efficient brain fuel when glucose use is impaired—C10-containing MCTs are being studied as “ketogenic adjuncts” for age-related memory concerns and mild cognitive impairment. Narrative and systematic reviews summarize trials in which MCT supplementation raised ketones and, in some cases, improved specific cognitive domains (often more evident in individuals without the APOE ε4 genotype). While many studies include both C8 and C10, several discuss C10-specific neural actions (e.g., AMPA modulation) alongside ketone-based mechanisms. The bottom line: early evidence suggests MCTs can support brain energy and occasionally cognition, but results vary and dosing, duration, and individual factors matter.
3) Rapid energy and metabolic flexibility
In everyday settings, many people use C8/C10 MCT oil for a quick, stomach-to-energy boost—especially when training or working in cognitively demanding environments. The liver can convert a portion of MCTs into ketones even when carbohydrate intake is not strictly restricted, which some users perceive as sustained energy without jitters. Research in exercise performance is mixed: some trials observe no clear ergogenic effect despite higher ketones, suggesting the timing, emulsification, and total dose influence outcomes. Still, the predictable absorption and oxidation of MCTs make them a useful tool when quick, digestible calories are needed.
4) Clinical nutrition and malabsorption
Because MCTs bypass many steps required to digest and absorb long-chain fats, clinicians have used them for decades in malabsorptive conditions (e.g., pancreatic insufficiency, certain post-surgical states, chylous leaks). In these contexts, C10-containing MCTs can provide calorie support with less dependence on bile and pancreatic enzymes. Importantly, this is a medical nutrition use case: patients still need essential fatty acids from other sources to prevent deficiency over time.
What benefits are not solid yet?
Weight loss claims around MCTs are often overstated. While MCTs can slightly increase fat oxidation and thermogenesis, long-term, clinically meaningful weight loss is not guaranteed. Similarly, early signals for mood, autism spectrum features, or broad athletic gains remain exploratory. For decanoic acid specifically, non-neurologic claims (e.g., “immune boosting,” “anti-cancer,” or generalized “detox”) are not supported by robust human data at this time.
Who seems to benefit most right now?
- Children or adults with drug-resistant epilepsy using clinician-supervised ketogenic or C10-enriched protocols.
- Adults seeking targeted brain-energy support where cognition is vulnerable (e.g., mild cognitive impairment), recognizing that responses vary.
- Patients who require easily absorbed calories in malabsorption syndromes, under dietitian guidance.
How to use decanoic acid
Choose a format that matches your goal
- General wellness or cognitive support: Most consumers use a liquid MCT oil containing both C8 and C10. Labels often list the proportion (e.g., 60% C8 / 40% C10). If you specifically want more C10 (for neurological reasons), look for “C10-enriched” or “C10 dominant” products.
- Therapeutic epilepsy: Medical foods or dietetic protocols may specify decanoic-to-octanoic ratios and total energy targets. These regimens are designed and monitored by clinicians; do not self-implement.
- Clinical nutrition: In malabsorption care plans, MCTs are mixed into meals or modular formulas to boost calories without demanding heavy digestive processing. A registered dietitian typically customizes the plan.
Timing, mixing, and cooking
- With meals is best. Taking MCTs, including C10, with food reduces the likelihood of gastrointestinal side effects.
- Start low, go slow. Begin with 5–10 mL (about 1–2 teaspoons) once daily, then add another 5 mL every 3–4 days as tolerated, splitting doses across meals.
- Blend smartly. MCT oil mixes easily with smoothies, yogurt, oatmeal, or coffee (use a small amount first to assess tolerance). Emulsified or powdered MCTs can be gentler on the stomach for some people.
- Heat carefully. MCT oils have a relatively low smoke point. Reserve them for low-heat applications; avoid frying. If cooking with MCTs, keep temperatures below roughly 150 °C (302 °F), and consider adding after cooking instead.
Stacking with diet patterns
- Lower-carb or time-restricted eating: C10-containing MCTs can help maintain energy during fasting windows or low-carb meals by increasing circulating ketones.
- Ketogenic therapy: In clinical keto programs, C10 is one lever among many (macronutrient ratios, total calories, micronutrient coverage). Adherence and dietetic monitoring matter more than any single supplement.
- Balanced diets: If you are not restricting carbohydrates, MCTs can still offer quick fuel; just account for calories and avoid displacing foods that provide essential fatty acids and fat-soluble vitamins.
Label literacy and quality
- Look for clear C8/C10 percentages and the absence of long-chain fillers.
- Select brands that provide lot testing for purity and contaminants.
- If you need a palm-free option, choose MCTs sourced from coconut.
Special populations and context
- Children and teens: Use only under medical supervision, particularly in epilepsy.
- Older adults: Start conservatively to minimize GI effects; consider emulsified forms.
- Athletes: Trial low doses well before competition to gauge tolerance; many do not see performance gains from acute high dosing.
How much per day?
There is no official Recommended Dietary Allowance for decanoic acid. Practical intake comes from MCT oils that blend C8 and C10, or from C10-enriched medical foods in clinical programs. Because tolerance varies, the safest approach is a gradual titration:
- Starter plan (general use): 5–10 mL once daily with food for 3–4 days.
- Step-up: Increase by 5–10 mL per day every few days, split across meals.
- Typical daily range: 10–30 mL/day (≈1–2 tablespoons) for many healthy adults focused on cognitive or energy support.
- Upper end (experienced users): Some tolerate up to 45–60 mL/day (3–4 tablespoons), but higher doses more often cause GI upset and are rarely necessary outside supervised protocols.
Therapeutic contexts
- C10-enriched ketogenic diets (epilepsy): Doses are individualized by weight, energy needs, and clinical goals. In a feasibility study of a decanoic-rich medical food, adult participants often targeted around 240 mL/day of the product, with children closer to 120 mL/day, alongside advice to limit refined sugars. That program demonstrated seizure reductions with low ketosis, consistent with C10’s receptor-level action.
- Cognition trials: Research protocols vary widely (e.g., ~6–20 g/day of MCTs in divided doses), often with both C8 and C10. Responses are heterogeneous, and longer durations seem more informative than single doses.
Dosing tips to improve tolerance
- Divide doses (e.g., 5–10 mL with breakfast and lunch) rather than taking a large bolus.
- Use emulsified or powdered forms if liquid oils cause cramping or loose stools.
- Pair with real food (protein and fiber help).
- Pause increases if you develop GI symptoms; resume at the last comfortable level.
When precise dosing matters
If you are using C10 for seizure management, do not rely on over-the-counter guesses. Follow a neurologist-led plan that specifies total calories, fat ratios, C10 targets, and lab monitoring. Likewise, if you have malabsorption or are on tube feeds, ask a dietitian to integrate MCTs into your regimen while maintaining essential fatty acid intake.
Safety and side effects
Common, usually dose-related effects
- Gastrointestinal: Bloating, abdominal cramping, nausea, and diarrhea are the most common complaints, especially with larger single doses or rapid titration. Taking MCTs with meals, splitting doses, and introducing slowly usually helps. Many trials report GI discomfort when intakes climb above roughly 30 g/day of MCTs.
- Taste and reflux: Some notice an oily mouthfeel or mild reflux; switching to emulsified or powdered forms can help.
Metabolic and nutritional considerations
- Lipids: Compared with long-chain fats, MCTs often have neutral effects on standard lipid panels in mixed diets, but responses vary by individual and background diet. If you have dyslipidemia, monitor lipids after introducing regular MCTs.
- Essential fatty acids: MCTs contain no essential omega-6 or omega-3 fats. If MCTs provide a large share of your dietary fat for weeks, be sure to consume foods rich in essential fatty acids (e.g., vegetable oils, nuts, seeds, fish) to avoid deficiency.
- Ketosis and glucose: MCTs can modestly raise ketones and, in some contexts, may influence glycemic patterns. People on medications that affect glucose should monitor as they adjust intake.
Who should avoid unsupervised use
- Significant liver disease: MCTs, including C10, are largely processed in the liver. Use only with clinician oversight in cirrhosis, active hepatitis, or severe hepatic impairment.
- Known fatty-acid oxidation disorders or carnitine metabolism defects: Specialized medical care is required.
- Active GI flares: In conditions with severe diarrhea or malabsorption, start only within a structured nutrition plan.
- Pregnancy and lactation: Food-level intakes from coconut or dairy are generally regarded as safe; concentrated supplemental MCTs should be discussed with your obstetric provider.
Medication and therapy considerations
- Antiepileptic drugs: Decanoic acid targets AMPA receptors; some antiseizure medications (e.g., perampanel) work on related pathways. Any stacking should be coordinated by your neurologist to balance efficacy and sedation risks.
- Surgery and anesthesia: Follow pre-op fasting instructions; fats can delay gastric emptying.
Warning signs to stop and seek care
- Persistent vomiting, severe abdominal pain, new jaundice, confusion, or signs of dehydration warrant medical evaluation. In therapeutic keto programs, regular labs (electrolytes, lipids, carnitine when indicated) are standard.
Quality and contamination
Choose reputable products with third-party testing. Poor-quality oils can oxidize and worsen GI tolerance.
What the science says
Mechanism: beyond ketones
A pivotal line of research shows that decanoic acid directly and non-competitively inhibits AMPA-type glutamate receptors, reducing excitatory neurotransmission implicated in seizures. This is distinct from the classic ketogenic model where benefits arise solely from raised ketones. Electrophysiology and brain-slice experiments demonstrate C10’s receptor-level effects at concentrations relevant to ketogenic therapy. These findings help explain why some patients improve on C10-enriched regimens even when blood ketone levels remain low.
Clinical neurology: where evidence is strongest
- C10-enriched ketogenic diet (pediatrics): In a randomized crossover pilot, a C10-enriched ketogenic diet achieved seizure reductions comparable to, and in some cases greater than, a classic ketogenic diet over eight weeks per phase, with manageable adverse effects. While small and preliminary, the study is important because it isolates the C10-enrichment variable within an otherwise standardized ketogenic framework.
- Decanoic-rich medical food (mixed ages): An open-label feasibility program gradually introduced a C10-heavy medical food (adults typically around 240 mL/day; children around 120 mL/day) while advising participants to limit refined sugars. Completion and tolerability were good; average seizure or paroxysmal event frequency fell, and reductions correlated with plasma C8/C10—not with beta-hydroxybutyrate—supporting a non-ketone mechanism.
Cognition and aging: cautious optimism
Narrative and systematic reviews of MCT supplementation report that in older adults with or without mild cognitive impairment, raising ketones with C8/C10 oils can improve some cognitive tasks in certain subgroups (e.g., APOE ε4 negative). Heterogeneity is substantial: study designs, doses, durations, and outcome measures vary widely. Most authors conclude MCTs are promising for brain energy support, yet larger, longer trials with standardized protocols are needed. Importantly, C10’s receptor-level actions in the brain could complement ketone-mediated effects, but that synergy remains to be tested rigorously in humans.
Metabolism and clinical nutrition
Decades of experience support MCTs as efficient calories in malabsorption. Reviews emphasize their rapid absorption and oxidation, lack of need for bile or pancreatic enzymes, and utility in specialized formulas. For the general population, MCTs can nudge fat oxidation, but long-term effects on weight and cardiometabolic risk depend far more on overall diet pattern and energy balance than on a single fat source.
Limitations and research gaps
- Many human trials pool C8 and C10, making it hard to assign effects specifically to decanoic acid.
- Sample sizes are often small; blinding is challenging due to taste and GI effects.
- Safety beyond GI tolerance is reassuring in the short term, but long-term, high-dose C10 data in diverse populations are limited.
- Standardized outcome measures in cognition and quality-of-life domains are needed to compare across studies.
Practical takeaway from the evidence
If your goal is seizure management, the science and clinical experience are strong enough to justify considering a C10-enriched approach—but only within a supervised ketogenic program. If your goal is brain-energy support, a modest, well-tolerated MCT routine that includes C10 can be reasonable to try, with realistic expectations and attention to overall nutrition.
References
- Seizure control by decanoic acid through direct AMPA receptor inhibition (2016).
- K.Vita: a feasibility study of a blend of medium chain triglycerides to manage drug-resistant epilepsy (2021).
- Decanoic acid-enriched ketogenic diet in refractory epilepsy (2025).
- Applications of Medium-Chain Triglycerides in Foods (2022).
- Supplementation of Regular Diet With Medium-Chain Triglycerides for Procognitive Effects: A Narrative Review (2022).
Disclaimer
This article is for informational purposes only and does not constitute medical advice. Decanoic acid and MCT products can affect nutrition, metabolism, and—when used therapeutically—neurologic outcomes. Do not start or modify ketogenic or C10-enriched regimens without guidance from a qualified clinician. Always consult your healthcare professional about your specific health conditions, medications, and goals.
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