Caprylic Acid: What It Is, Benefits, Dosage, and Sources

Nutrienting Team

February 9, 202611 min read

Caprylic acid, also known as octanoic acid, is a medium-chain fatty acid (MCFA) naturally found in certain foods and supplements. It's often recognized for its potential role in supporting various aspects of health, particularly concerning gut health and antimicrobial properties. Unlike longer-chain fatty acids, caprylic acid is metabolized differently by the body, leading to its unique characteristics and applications. This article explains what caprylic acid is, its potential benefits, typical dosages, and where to find it.

Understanding Caprylic Acid: A Closer Look

Caprylic acid is a saturated fatty acid with an eight-carbon chain, which is where its alternative name, octanoic acid, originates. This relatively short chain length classifies it as a medium-chain fatty acid, a group that also includes caproic acid (C6), capric acid (C10), and lauric acid (C12).

The key distinction of MCFAs like caprylic acid lies in their metabolic pathway. Unlike long-chain fatty acids (LCFAs) that require bile salts for digestion and transportation through the lymphatic system, MCFAs are absorbed directly from the gut into the bloodstream and transported to the liver. In the liver, they can be rapidly converted into energy or ketones. This efficient metabolism is a primary reason for the interest in caprylic acid and other MCFAs.

While not a new discovery, caprylic acid has gained attention in wellness communities for its purported ability to address imbalances in the body's microbial environment. Its presence in natural sources like coconut oil has further fueled this interest, leading to its inclusion in various dietary supplements and topical products.

Caprylic Acid Benefits, Dosage, and Side Effects

The perceived benefits of caprylic acid primarily stem from its proposed antimicrobial and anti-inflammatory properties. However, it's important to approach these claims with a balanced perspective, understanding that research is ongoing and individual responses can vary.

Potential Benefits

Antifungal Properties: One of the most frequently cited benefits of caprylic acid is its potential to combat certain types of fungi, particularly Candida albicans. This yeast is a common inhabitant of the human gut and mucous membranes, but an overgrowth can lead to conditions like candidiasis. Research suggests that caprylic acid can disrupt the cell wall of Candida, inhibiting its growth and biofilm formation.
Antibacterial Effects: Beyond fungi, caprylic acid has also shown some activity against certain bacteria. This broad-spectrum action contributes to its reputation as a substance that can help balance the gut microbiome.
Gut Health Support: By potentially managing the overgrowth of undesirable microorganisms, caprylic acid may contribute to a healthier gut environment. A balanced microbiome is linked to improved digestion, nutrient absorption, and overall immune function.
Skin Health: Due to its antimicrobial properties, caprylic acid is sometimes used topically in skincare products. It may help address certain skin conditions related to microbial imbalances, though direct evidence for specific conditions is often anecdotal or limited to in-vitro studies.
Energy Source: As an MCFA, caprylic acid is readily converted into energy. This makes it a component of some ketogenic diets, where it can be used to produce ketones, an alternative fuel source for the brain and body.

Dosage Considerations

There is no universally established recommended daily allowance for caprylic acid, as it is not considered an essential nutrient in the same way vitamins or minerals are. Dosages typically vary based on the intended use and the form of the supplement.

For General Gut Health/Antifungal Support: Supplement dosages often range from 300 mg to 1,000 mg, taken two to three times daily with meals. It's common for individuals to start with a lower dose and gradually increase it to assess tolerance.
Topical Applications: When used in skincare, caprylic acid's concentration will depend on the specific product formulation.

Important Note: It is always advisable to consult with a healthcare professional before starting any new supplement regimen, especially when considering dosages, to ensure it's appropriate for your individual health needs and to avoid potential interactions with other medications.

Potential Side Effects

While generally considered safe for most people when consumed in moderate amounts, caprylic acid supplements can lead to side effects, particularly if taken in high doses or on an empty stomach. Common side effects include:

Gastrointestinal Distress: Nausea, stomach upset, diarrhea, and indigestion are the most frequently reported side effects. These can often be mitigated by taking the supplement with food and starting with a lower dose.
"Die-off" Symptoms (Herxheimer Reaction): In individuals using caprylic acid for antimicrobial purposes, particularly against Candida overgrowth, some may experience temporary worsening of symptoms. This is sometimes referred to as a "die-off" or Herxheimer reaction, attributed to the release of toxins from dying microorganisms. Symptoms can include headache, fatigue, flu-like symptoms, and skin rash. While often interpreted as a sign the treatment is working, it's crucial to distinguish this from an adverse reaction and consult a healthcare provider if symptoms are severe or persistent.
Allergic Reactions: Though rare, allergic reactions to caprylic acid or its source (e.g., coconut) are possible.
Liver Concerns: The question "Is caprylic acid hard on the liver?" is occasionally raised. Given that MCFAs are processed directly by the liver, individuals with pre-existing liver conditions should exercise caution and consult their doctor before using caprylic acid supplements. For healthy individuals, there is generally no evidence to suggest that typical supplemental doses are harmful to the liver.

Caprylic Acid Sources: Where to Find It

Caprylic acid is present in various natural sources, primarily certain fats and oils. Understanding these sources can help you incorporate it into your diet or identify its presence in products.

Dietary Sources

The most prominent dietary sources of caprylic acid are:

Coconut Oil: This is perhaps the best-known and richest natural source of caprylic acid, typically containing about 6-8% caprylic acid. It also contains other MCFAs like lauric acid and capric acid.
Palm Oil/Palm Kernel Oil: These oils also contain significant amounts of MCFAs, including caprylic acid.
Dairy Products: Small amounts of caprylic acid are found in the milk fat of various mammals, including cows, goats, and sheep. This means dairy products like butter, cheese, and milk contain trace amounts. Goat's milk, in particular, is often noted for a higher concentration of medium-chain fatty acids compared to cow's milk.
Human Breast Milk: Human breast milk naturally contains caprylic acid, contributing to its protective properties for infants.

Supplemental Sources

For those seeking higher, more concentrated doses of caprylic acid, supplements are available. These typically come in capsule or liquid forms.

Caprylic Acid Supplements: These are often formulated to contain a high percentage of pure caprylic acid, sometimes derived from coconut or palm oil.
MCT Oil: Medium-chain triglyceride (MCT) oil is a popular supplement that contains a blend of MCFAs, often including caprylic acid (C8) and capric acid (C10), and sometimes caproic acid (C6) and lauric acid (C12). Some MCT oils are specifically formulated to be high in C8, labeled as "C8 MCT oil." This form is favored by some for its rapid conversion to ketones.

Comparison of Caprylic Acid Sources

Source	Primary Form	Typical Caprylic Acid Content	Advantages	Considerations
Coconut Oil	Food ingredient, cooking oil	6-8%	Natural, widely available, culinary uses	Lower concentration, also contains other fats, higher intake required for therapeutic doses
Palm Kernel Oil	Food ingredient, industrial	~3-5%	Natural, industrial applications	Environmental concerns with palm oil production, not typically consumed directly
Dairy Products	Food ingredient	Trace amounts	Part of a balanced diet	Very low concentration, not a primary source for specific caprylic acid benefits
Caprylic Acid Supp.	Capsule, liquid	High (often >95%)	Concentrated dose, targeted benefits	Potential for side effects, requires careful dosing, often higher cost
MCT Oil (C8 Rich)	Liquid supplement, added to food	High (often 50-100% C8)	Rapid energy, ketone production, versatile	May cause GI upset, not pure caprylic acid (often C8/C10 blend)

Caprylic Acid in Skincare: EWG Skin Deep® Perspective

The Environmental Working Group (EWG) Skin Deep® database often lists caprylic acid as an ingredient in cosmetics and personal care products. In this context, it's typically referred to as "Caprylic Acid" or "Octanoic Acid" and is used for several purposes:

Emollient: It can help soften and smooth the skin.
Emulsifier: It helps mix oil and water-based ingredients, preventing separation in formulations.
Fragrance Ingredient: It can contribute to the scent of a product.
Antimicrobial Agent: Its natural antimicrobial properties are leveraged to help preserve products and potentially benefit skin health.

The EWG generally rates caprylic acid as a low-hazard ingredient in cosmetics, indicating it has a low concern for cancer, developmental and reproductive toxicity, and allergies or immunotoxicity. However, individual sensitivities are always possible with any skincare ingredient. When seeing "Caprylic Acid" on an ingredient list, it's usually referring to its role as a functional ingredient in the product rather than a therapeutic dose for internal health.

Caprylic Acid: Uses, Interactions, Mechanism of Action

To further clarify caprylic acid's role, it's helpful to understand its primary mechanisms and potential interactions.

Mechanism of Action

The proposed mechanisms behind caprylic acid's effects largely revolve around its interaction with microbial cell membranes:

Cell Membrane Disruption: For fungi like Candida, caprylic acid is thought to integrate into the fungal cell membrane, increasing its permeability. This disrupts the cell's integrity, leading to leakage of cellular contents and ultimately cell death. It may also inhibit the formation of biofilms, which are protective layers that make fungi and bacteria more resistant to treatments.
Metabolic Interference: Some research suggests caprylic acid may interfere with the metabolic processes of certain microorganisms, further hindering their growth and survival.

Interactions

While specific drug interactions with caprylic acid are not extensively documented, general considerations for supplements apply:

Antifungal Medications: If you are taking prescription antifungal medications, discuss caprylic acid supplementation with your doctor. While it might theoretically enhance effects, it could also lead to unexpected interactions or side effects.
Blood Thinners: As with many supplements, there's a theoretical, albeit unproven, risk of interactions with blood-thinning medications. Always consult a healthcare provider.
Digestive Issues: Individuals with sensitive digestive systems or conditions like Irritable Bowel Syndrome (IBS) may be more prone to gastrointestinal side effects.

Practical Applications

Beyond its potential health benefits, caprylic acid has several practical applications:

Food Industry: It's used as an emulsifier, flavor enhancer, and antimicrobial agent in some processed foods.
Cosmetics and Personal Care: As mentioned, it's an ingredient in many skincare products, shampoos, and soaps.
Industrial Uses: Caprylic acid and its derivatives are used in the production of esters, lubricants, and other industrial chemicals.

FAQ

What does caprylic acid do to your body?

Caprylic acid is primarily known for its potential to act as an antimicrobial agent, particularly against certain fungi like Candida albicans, and some bacteria. When consumed, it is efficiently metabolized by the liver, providing a quick source of energy or being converted into ketones. It may help support a balanced gut microbiome and can also be used topically for its skin-conditioning and antimicrobial properties.

Is caprylic acid hard on the liver?

For healthy individuals taking caprylic acid in typical supplemental doses, there is generally no evidence to suggest it is harmful to the liver. MCFAs, including caprylic acid, are processed directly by the liver, making their metabolism more efficient than that of long-chain fatty acids. However, individuals with pre-existing liver conditions should always consult their healthcare provider before using caprylic acid or any other supplement.

What foods are high in caprylic acid?

The primary food source high in caprylic acid is coconut oil, which typically contains about 6-8% caprylic acid. Palm kernel oil also contains caprylic acid. Additionally, small amounts of caprylic acid are found in the milk fat of various mammals, meaning dairy products like butter, cheese, and milk contain trace amounts. Goat's milk, in particular, is noted for a slightly higher concentration of medium-chain fatty acids compared to cow's milk.

Conclusion

Caprylic acid, an eight-carbon medium-chain fatty acid, stands out for its unique metabolic pathway and its potential antimicrobial properties. Found naturally in coconut oil and certain dairy products, it's also available in concentrated supplement forms. Its primary appeal lies in supporting gut health, particularly in managing microbial balance, and it finds applications in skincare. While generally well-tolerated, understanding appropriate dosages and potential side effects is crucial. As with any supplement, consulting a healthcare professional before incorporating caprylic acid into your regimen is a prudent step to ensure it aligns with your individual health needs and circumstances.