The Health Benefits of Caprylic Acid

Fatty acid may help treat epilepsy, IBD, and Alzheimer's disease

Cracked open coconut

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Caprylic acid, also called octanoic acid, is an oily liquid found in the milk of certain mammals as well as coconut oil and palm oil. It is a medium-chain saturated fatty acid widely used in the manufacture of dyes, perfumes, sanitizers, and disinfections.

Caprylic acid can also be formulated into dietary supplements, where it is said to have antimicrobial and anti-inflammatory properties. It is a popular ingredient in many anti-aging creams and is the main component of medium-chain triglyceride (MCT) oil, a dietary supplement believed to aid in weight loss and athletic performance.

Health Benefits

Caprylic acid, taken either by mouth or used topically, is thought to treat a number of health conditions, including:

Caprylic acid is also sometimes used to prevent hypoalbuminemia (low albumin) in people undergoing dialysis. Caused in part by the low-protein diet people with severe kidney disease need to maintain, hypoalbuminemia is a predictor of poor outcomes for people on dialysis.

Some of the abovelisted health claims are better supported by research than others. Here is what some of the current evidence says:

Fungal Infections

Caprylic acid supplements are commonly sold as an over-the-counter supplement for oral and vaginal candidiasis. Candidiasis is the medical term used to describe oral thrush and vaginal yeast infections, the conditions of which are associated with the Candida albicans fungi.

A 2017 study in the Journal of Medicinal Food concluded that caprylic acid was able to inhibit the growth of C. albicans in test-tube studies by arresting cell development at three different stages in its life cycle.

Despite the positive finding, there is no evidence an oral dose of caprylic acid can remain therapeutic once disseminated in the body. The concentration will likely be far too low to suppress an active yeast infection.

With that said, rinsing the mouth with MCT oil may aid in the treatment of oral thrush given its direct contact with affected tissue. Further research is needed.

Weight Loss

Popularly included in weight-loss products, caprylic acid is believed to work by suppressing hunger. In the human body, the "hunger hormone" ghrelin is activated whenever the stomach is empty. There is both acylated ghrelin, which contributes to hunger, and unacylated ghrelin, which is believed to improve glycemic control and suppress hunger.

It had long been assumed that caprylic acid enhances the production of unacylated ghrelin, thereby suppressing hunger and maintaining satiety (a feeling of fullness). But, a 2015 study in PLoS One reported a contradictory effect.

According to the researchers, lab rats fed a diet high in caprylic acid had no increase in their acylated ghrelin but instead had a significant decrease in unacylated ghrelin. Findings like these suggest that caprylic acid is unlikely to aid with weight loss.

This supports earlier research in which MCT oil (of which caprylic oil accounts for around 75% of the overall content) had no effect on either body composition, energy expenditure, or satiety.

Epilepsy

There is growing evidence that caprylic acid may help reduce the number of seizures in people with epilepsy. According to a 2013 study published in Case Reports in Neurological Medicine, doctors with Vanderbilt University Medical Center reported that a 43-year-old man with treatment-resistant epilepsy experienced a steep reduction in seizures after being prescribed a twice-daily, four-tablespoon dose of MCT oil.

Prior to MCT therapy, the man had multiple tonic-clonic seizures every day. After a month of MCT therapy, the number of seizures dropped to one every four days.

The results were supported by a 2015 study in the Journal of Pharmacology and Experimental Therapeutics in which mice with induced epilepsy achieved better seizure control when fed MCT oil compared to mice that weren't.

Alzheimer's Disease

There is some evidence that caprylic can slow the progression of mild to moderate Alzheimer's disease. A 2013 review of studies in Neuropsychiatric Disease and Treatment reported that adults with Alzheimer's given a daily 20-gram dose of caprylic acid experienced a slower decline in cognitive function than those who weren't. The results were monitored using the Mini-Mental State Examination (MMSE) test.

Caprylic acid is also the active ingredient of a supplement called Axona, which the manufacturers claim can aid in the treatment of Alzheimer's disease. Despite undergoing Phase I and Phase II clinical trials (in which Axona showed some benefit), the manufacturers decided to skip Phase III studies and market Axona as a "medical food" for people with Alzheimer's.

Further research is needed to provide stronger evidence of caprylic acid's benefits in treating Alzheimer's disease.

Inflammatory Bowel Disease

Caprylic acid may aid in the control of inflammatory bowel diseases (IBD), including Crohn's disease and the typically more severe ulcerative colitis.

According to a 2019 study in Inflammatory Bowel Disease, a daily 2-gram dose of caprylic acid prevented the relapse of symptoms in adults with ulcerative colitis. Endoscopic and tissue biopsy evaluations confirmed a reduction in inflammation and ulcerative damage to the lining of the intestinal tract compared to pretreatment values.

Although the effectiveness of caprylic acid has varied between studies, medium-chain fatty acids are believed to suppress the production of interleukin-8 (IL-8), an inflammatory cytokine found in excessive quantities in people with IBD.

Possible Side Effects

Caprylic acid supplements are generally considered safe if used as prescribed. Common side effects include nausea, flatulence, constipation, heartburn, indigestion, and diarrhea. High doses may trigger an abnormal drop in calcium levels (hypocalcemia), causing growth problems in children and an increased risk of brittle bones in people with osteoporosis.

Caprylic acid may not be appropriate for people with liver disease or hypotension (low blood pressure) as an increased fatty acid intake is known to complicate both conditions.

Caprylic acids should be avoided in people with medium-chain acyl-CoA dehydrogenase (MCAD) deficiency who are unable to break down fatty acids efficiently. The excessive build-up of caprylic acid can trigger hypoglycemia (low blood sugar), vomiting, and, in severe cases, coma.

The safety of caprylic acid in children, pregnant women, and nursing mothers has not been established. For safety sake, it is best to avoid caprylic acid unless under the supervision of qualified pediatrician or OB/GYN.

It is not known if caprylic acid supplements can interact with other medications.

Dosage and Preparation

Widely available for purchase online, caprylic acid supplements can also be found in drugstores, natural food shops, and stores specializing in dietary supplements.

When formulated as capsules, caprylic acid is typically sold as "fungal defense" supplement against yeast infections and thrush. The majority of these products are sold in multi-ingredient supplements rather than as a dedicated caprylic acid supplement.

More readily available are MCT oils that are sold in either large, liter-sized containers or marketed as a ketogenic sports supplement (typically in smaller, more expensive quantities).

There are no guidelines for the appropriate use of caprylic acid or MCT oil. Studies exploring the benefits of caprylic acid in people with Alzheimer's have used up to 20 grams (20,000 milligrams) per day, although intake of this level could potentially be harmful. Most co-formulated supplements contain 500 milligrams of caprylic acid, a far safer amount.

The appropriate dosing of MCT oil is far less certain since the source of the oil and production techniques can vary. Studies have reported safe use with up to eight tablespoons per day, although this method of dosing is highly inaccurate.

With no consolidated guidelines to direct your dosing, the best rule of thumb is to take the supplement as prescribed and to never exceed the recommended daily dose.

If anything, start at the lowest possible dose and increase gradually as tolerated.

What to Look For

Dietary supplements are not strictly regulated in the United States. To ensure quality and safety, opt for brands that have been voluntarily submitted for testing by an independent certifying body like the U.S. Pharmacopeia (USP), NSF International, or ConsumerLab. In this way, you can be better assured that you are getting the ingredients (and ingredient amounts) listed on the product label.

When buying MCT oil, opt for brands that are pure and certified organic. Pure simply means that there are no ingredients (like vegetable oils). The product should carry the USDA stamp verifying that it is organic.

Always read the product label when buying a supplement if only to check for additives or other ingredients you may be allergic to. If in doubt, look for products labeled "hypoallergenic."

MCT oil doesn't require refrigeration, although it may extend its shelf life. If stored in a cool, dry room, MCT oil can last for up to two years. Never used MCT oil if it has changed in consistency or coloration and/or emits a rancid odor. MCT oil does not thicken when refrigerated.

Never use a supplement past its expiration date.

Common Questions

Which foods have the highest amount of caprylic acid?

Coconut oil is probably the best source overall. Comprised of approximately 60% medium-chain fatty acids, coconut oil is generally well tolerated and offers numerous health benefits. Lauric acid accounts for around half of the fatty acid content, with smaller quantities of caprylic and capric acid.

Palm kernel oil comes in a close second, with a medium-chain fatty acid content of around 50%.

Despite their potential benefits, both coconut and palm kernel oil are high in saturated fat. With more than 85% saturated fat, the high consumption of either of these oils can raise your risk of cardiovascular disease.

By contrast, milk and other dairy products contain far lower amounts of caprylic acid (1% to 5%) but, as a dietary source, may be healthier options.

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Article Sources

  1.  Rego Costa AC, Rosado EL, Soares-Mota M. Influence of the dietary intake of medium-chain triglycerides on body composition, energy expenditure and satiety: a systematic reviewNutr Hosp. 2012;27(1):103-8. doi:10.1590/S0212-16112012000100011.

  2. Thaipisuttikul P, Galvin JE. Use of medical foods and nutritional approaches in the treatment of Alzheimer’s disease. Clin Pract (Lond). 2012 Mar;9(2):199-209. doi:10.2217/cpr.12.3.

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