Overview

Caprylic acid is a medium-chain fatty acid your body can use as a source of energy. It may help some people use ketones for energy. But the benefits of taking caprylic acid for any other use are not well defined. Some common side effects of caprylic acid include taste changes, diarrhea, nausea, and stomach cramps. Before taking caprylic acid, make sure to tell your health care provider about any health conditions you have or medicines you are taking.

Uses

What is caprylic acid used for?

Caprylic acid is commonly used to help you achieve ketosis, which is sometimes used for weight loss.

It may also be used for a variety of other reasons, although its benefits are not well defined. Some common reasons that people use caprylic acid include the following.

• Antibacterial effects
• Antifungal effects
• Brain health
• Skin health (topical use)

Note: The FDA has not reviewed caprylic acid for safety and effectiveness. Learn more about dietary supplements here.

If you have symptoms of an infection, do not try to treat these symptoms on your own. Talk to your health care provider about treatment options.

Caprylic acid is available over the counter; it can be present in many skincare products and is available as a dietary supplement. It is also one of the three main ingredients in medium-chain triglycerides (MCTs) dietary supplements.

How does caprylic acid work (mechanism of action)?

Caprylic acid, also known as C8 and octanoic acid, is a medium-chain fatty acid found in dairy products and certain oils, such as coconut oil and palm kernel oil.

Your body usually uses sugar (carbohydrates) as a source of energy. But it is also able to use fat as a source of energy, especially at times when there is not enough sugar available. Using a process called ketosis, your body turns fat into ketone bodies. Your heart, brain, and other organs are able to use ketone bodies as a source of energy. Your body may enter ketosis during a very long workout or if you are following a very low carbohydrate diet such as the ketogenic diet.

Most of the fats in the foods that you eat are long fatty acids, which are hard for your body to break down into ketone bodies (energy). Caprylic acid, on the other hand, can be broken down by your body much faster. As a result, taking caprylic acid by mouth can help your body enter into ketosis, increasing the levels of ketone bodies in your blood. But it is not clear if taking caprylic acid helps with weight loss. It is possible that caprylic may work for some people better than others, but it is not clear who is most likely to benefit.

The antibacterial and antifungal effects of caprylic acid seem to be related to its ability to damage cell walls of certain bacteria and fungi. But it is not clear if caprylic acid works to treat infections. The benefits of caprylic acid for antibacterial and antifungal effects are not well defined.

Caprylic acid has been studied in a small number of people with cognitive impairment, including some people with Alzheimer’s disease. Caprylic acid does not seem to reverse established cognitive impairment. There is some data to show that higher levels of caprylic acid may be associated with a reduced risk of cognitive impairment. However, it is not clear if taking caprylic acid supplements is linked with a reduced risk of cognitive impairment. The benefits of taking caprylic acid for brain health are not well defined.

How should I store caprylic acid?

You should store caprylic acid according to the product label. Most dietary supplements should be kept in a cool, dry location that is out of the reach of children and pets and not in direct sunlight.

Side Effects

What are the most common side effects of caprylic acid?

The most common side effects of caprylic acid are listed below. These side effects may vary depending on the dose you are taking or the specific product you are using. Tell your health care provider if you have any of these side effects that bother you.

• Nausea
• Stomach cramps
• Diarrhea
• Taste changes

There may be other side effects of caprylic acid that are not listed here. Contact your health care provider if you think you are having a side effect of a supplement. In the U.S., you can report side effects to the FDA at www.safetyreporting.hhs.gov or by calling 888-SAFEFOOD (888-723-3366). In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of caprylic acid?

While less common, the most serious side effects of caprylic acid are described below, along with what to do if they happen.

Severe Allergic Reactions. Caprylic acid may cause allergic reactions, which can be serious. Stop taking caprylic acid and get help right away if you have any of the following symptoms of a serious allergic reaction.

• Breathing problems or wheezing
• Racing heart
• Fever or general ill feeling
• Swollen lymph nodes
• Swelling of the face, lips, mouth, tongue, or throat
• Trouble swallowing or throat tightness
• Itching or skin rash
• Bumps on the skin called hives that can be red, pink, white, or brown depending on your skin tone
• Nausea or vomiting
• Dizziness, feeling lightheaded, or fainting
• Stomach cramps
• Joint pain

Precautions

Who should not use caprylic acid?

Allergies to Ingredients. People who are allergic to any of the following should not take caprylic acid.

• Caprylic acid
• Medium-chain fatty acids (MCFAs)
• Medium-chain triglycerides (MCTs)
• Octanoic acid
• Any of the ingredients in the specific product

Your pharmacist can tell you all of the ingredients in the specific caprylic acid products they stock.

What should I know about caprylic acid before using it?

Caprylic acid is a dietary supplement. It cannot be marketed to treat or cure a disease.

Read and follow the directions on the specific product you are taking, or take it as recommended by your health care provider.

Keep caprylic acid out of the reach of children.

Caprylic acid may be found in products that are marketed as “keto supplements.” These supplements may include many ingredients that have different effects in the body. Read the product label closely to see which ingredients it contains.

If you are using caprylic acid powder, use an appropriate measuring device to measure the powder, such as the device included with the product. Read the label carefully, and measure the amount stated on the label.

If you are using caprylic acid oil, use an accurate measuring device to measure your dose. A household spoon is not an accurate measuring device and may cause you to take the wrong dose.

Most caprylic acid oils and powders should be added to foods or thick drinks, such as smoothies. Taking caprylic acid with food can help reduce the risk of having certain side effects.

The FDA has not tested caprylic acid products to confirm that they contain the ingredients stated on their labels. Some dietary supplements have been tested by third-party organizations to confirm that they contain the ingredients listed on their labels and do not contain any harmful chemicals. Learn more about how to choose a safe dietary supplement product here.

What should I tell my health care provider before using caprylic acid?

Tell your health care provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them know if caprylic acid is right for you.

In particular, make sure that you discuss any of the following.

Current and Past Health Conditions.Tell your health care provider if you have any of the following.

• Liver problems
• Current infection
• Diabetes
• Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency, which is a rare inherited disorder
• Follow a very low carbohydrate diet, such as the ketogenic diet

Other Medicines and Supplements.Caprylic acid may interact with other medicines and supplements. Before taking caprylic acid, tell your health care provider about any prescription or OTC medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details.

Pregnancy. It is not known if or how caprylic acid could affect pregnancy or harm a fetus. Tell your health care provider if you are pregnant or plan to become pregnant.

Breastfeeding. Caprylic acid passes into breast milk. Tell your health care provider if you are breastfeeding or plan to breastfeed.

Interactions

Does caprylic acid interact with foods or drinks?

Taking caprylic acid with food may help reduce certain side effects. But changing the type of food you eat may change the way that caprylic acid works. When possible, take caprylic acid with a similar type of food each day. If you have any questions, speak with a health care provider.

It is unknown if drinking alcohol will affect caprylic acid.

Does caprylic acid interact with medicines (drug interactions)?

Always tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

In particular, make sure that you discuss if you are taking triheptanoin (Dojolvi), which is a medicine used for a rare metabolic disorder, before taking caprylic acid.

The interactions between caprylic acid and medicines are not fully understood. As with most dietary supplements, the research on drug interactions with caprylic acid is incomplete. Always check with your health care provider before taking caprylic acid with any medicines.

Dosing

What should I do if I accidentally use too much caprylic acid?

If you or someone else has used too much caprylic acid, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

Caprylic acid comes in many forms, including oils, capsules, and powders. The dose may vary depending on your reason for use. Read the product label closely, and speak with a health care provider about how to take caprylic acid safely. Do not take double or extra doses, even if you miss a dose.