Is Undecenoic Acid Good for Candida?

My Name is Eric Bakker (N.D.) & I'm Here to Teach You the Candida Cleanse I've Successfully Used On Over 60,000 Patients At My New Zealand Clinic

Is Undecenoic Acid Good for Candida?

There’s lots of information online on different Candida websites about undecenoic acid and how to use it.

A lot of this information is put together by people who’ve never seen any patients, but there’s also plenty of information by people like me who do see patients.

Undecenoic acid (also known as undecylenic acid or 10-undecenoic acid, they all refer to the came thing) has been used as an anti-fungal for a long, long time. The food industry first started using it in
 1949 to inhibit yeasts and fungi.

And as you’ll soon learn, it’s still just as effective today.

Be sure to also watch a few of the videos I've embedded into this page from my YouTube channel because you’ll get additional information there not covered below.

What is undecenoic acid and where does it come from?

As you’ve probably heard, undecenoic acid is a fatty acid distilled from caster bean oil.

It's produced by cracking castor bean oil under high pressure (meaning you can't get it just by consuming castor beans or castor bean oil).

It’s a very foul smelling liquid.

Pure undecenoic acid can irritate the skin & digestive tract if taken in isolation. That’s why salts of the acid have traditionally been used as these tend to be very well tolerated by the majority of people. These salts also have up to four times more anti-fungal activity so there’s no reason to seek out the liquid itself.

Undecenoic acid is also found naturally (in small amounts) in human sweat. Therefore you can imagine it’s not totally alien to the human body.

Can undecenoic acid really kill Candida?

The answer is yes. Undecenoic acid is HIGHLY effective at killing Candida.

One study conducted in 1938 by the American scientists Reck and Rosenfeld found salts made of undecenoic acid may
have 30 times more anti-fungal activity than even caprylic acid (another natural anti-fungal which I’ll talk about in a moment).

Another study — this one conducted in 1945 by scientists Shapiro and Rothman also from the USA — tested the effect of salt of undecenoic acid on 150 patients with skin fungal infections and found it to be highly effective against a wide range of fungi
including Candida itself.

So the first major study that proved the anti-fungal nature of undecenoic acid was itself done on Candida.

Salts made of undecenoic acid have been used topically to treat athlete’s food and toenail fungal infections
since at least World War II. They were the very first agents shown to get rid of foot fungus without causing irritation or side effects.

Salt powder made of undecenoic acid was also tested in a double blind clinical trial in 1980 by a scientist named Dr. Chretian from the USA. He found that 88% of foot fungus infection patients treated with undecenoic acid had 
zero fungus within 4 weeks compared to only 17% in the control group.

Undecenoic acid has even been shown to be effective at clearing up systemic fungal infections of the lungs (this was proven by the scientists Hopkins and Murphy in 1952).

Other studies conducted on children in 1949 by Dr. Henry Perlman found that the oral use of undecenoic acid can also be used to treat
psoriasis and other fungus related skin issues.

I’ve personally found undecenoic acid to be extremely well tolerated (meaning no side effects or strong reactions) by even the most yeast-sensitive patients.

How does undecenoic acid work?

Undecenoic acid works by inhibiting the growth of Candida in the small bowel and large intestine.

It stops Candida from growing to its pathogenic (hyphal) form. Undecenoic acid does this by attacking the cell surface of Candida and
causing it to become deformed and crumpled. This has been observed via electron microscope by Dr. Shi and colleagues in China after putting even low concentrations of undecenoic acid on Candida.

Undecenoic acid inhibits the enzymes Candida uses to grow and shift from one stage of its life cycle to another.

I’ve personally seen undecenoic acid stop the growth of several Candida strains in both the small and large intestine.

However, it is important to understand that while undecenoic acid is effective, it's best used in addition to several other anti-fungals that amplify its effect (which is the topic of the next section).

Why you should combine undecenoic acid with something called caprylic acid:

Many years ago I used to give undecenoic acid alone to Candida patients who came to my naturopathic clinic.

Then later on just
caprylic acid (another highly effective natural anti-fungal). But then I discovered that when you put these two acids together you get a much stronger or amplified effect.

So, caprylic acid is a fatty acid that comes from coconut. Coconut actually contains 3 of these acids, all of which are medium chain fatty acids (also known as MCT). If you’ve heard of MCT oil or MCT fats before, that’s what caprylic acid is.

It’s not as potent as undecenoic acid but acts on Candida in a very similar way. It’s also not something yeast can develop a resistance to (more on this in a moment).

I’m not going to go super in-depth into caprylic acid here. You can watch my YoutTube video on it on below if you like.

My naturopathic clinic has tried well over 100 Candida killing products in different combinations and I’ve consistently found undecenoic acid and caprylic acid to work better together. They kill off a wider range of Candida species when you combine them vs if you take them alone.

How to make undecenoic acid & caprylic acid even more effective:

I taught you that if you take undecenoic acid with caprylic acid (which comes from coconut) you get a stronger kill effect on a wider range of Candida species.

But you can amplify undecenoic acid EVEN MORE if you combine these two acids with something called Betaine HCL.  

Betaine HCL is another ingredient that works extremely well with a undecenoic / caprylic acid combination. Many people with Candida have pH issues in their small intestine which would inhibit the effect of undecenoic acid if betaine wasn't present.

Betaine helps because it lowers the pH a little in the environments where these two acids work together. 

Betaine also ensures undecenoic acid works exactly where it needs to, which is the duodenum and ileum (the two parts of the small bowel most effected by Candida). This is a very strategic combination you won't find in many supplements. 

Think of this undecenoic acid / caprylic acid / betaine combination as a shotgun approach vs a rifle approach. You end up with a broad spectrum effect that doesn’t just knock out Candida Albicans, but 19 other Candida strains as well. 

It also targets any bad bacteria that have teamed up with Candida & overgrown due to the toxic gut environment Candida creates for itself.

This is very important because in my experience doing thousands of comprehensive stool tests on patients — the majority of people who have Candida have also got dsybiotic (bad) bacteria in there as well that needs cleaning up.

That’s why I tell patients they shouldn’t take undecenoic acid alone & why I’m telling the same thing to you. 

So make sure whatever formula you take has all three of these at the very least. You’re really missing the boat if you’re not. Keep reading and I’ll give you some supplement recommendations at the bottom of this page.

Can Candida become resistant to undecenoic acid?

Resistance doesn’t occur with natural anti-fungals like undecenoic acid or the other ingredients I mentioned.

That only happens with drugs.


This has been confirmed many times with studies done on things like grapefruit seed extract, caprylic acid, undecenoic acid, clove, and other natural anti-fungals. It just doesn’t happen.

It happens with pharmaceutical drugs because they are synthetic. They’re only made up of one thing. They’ve got one ultra refined chemical compound with a very narrow band of action. Once Candida develops a resistance to this action, the pharmaceutical drug is done. 

Remember, Candida is very adaptive. If you only hit it with one action it will soon work out how to fool this action. And you know what happens next. The drug no longer works and the yeast comes back. And then you go back to the doctor who puts you on a a new drug and the cycle repeats again.

Natural anti-fungals are different. 

Undecenoic and caprylic acid doesn’t just contain one thing. They’ve got many different natural chemicals and compounds in there that make it up. That’s why I call it a shotgun effect. They attack Candida from many different angles so the yeast gets overwhelmed. It doesn’t know what hit it and it can’t fight back.

This is why I tell patients to get a natural broad spectrum formula and not go the pharmaceutical route. This way you don’t have to rotate several anti-fungal formulas and can just stick to one top quality proven formula long term. 

And this formula just continues to work because yeast can’t develop a resistance to it.

Can you get undecenoic acid just from eating castor beans?

As I mentioned previously, undecenoic acid is produced when castor bean oil is cracked under high pressures.

It’s a complex chemical process which is
why your digestive system can’t extract it from caster bean oil on its own.

Castor bean oil is a laxative by itself. It induces bowel movements. It clears out your intestines (often in the form of diarrhea) and leaves your system within two to three hours — so any anti-fungal activity, if it exists, wouldn't be active for long anyway due to how quicky castor bean oil leaves the digestive system.

There are 
no known food sources of undecenoic acid.

That’s why supplements are recommended. They allow undecenoic acid to stay active in your system from the moment it enters your mouth & all the way throughout the digestion process (which can last 24 hours or more).

Remember, undecenoic acid is found in small amounts in sweat so it’s not foreign to the human body.

Your body already uses it to prevent fungi from growing on your skin as a result of the added moisture that sweat produces (particularly in areas that don’t see as much sunlight such as under your arms).

Which form of undecenoic acid is best — gel capsules, tablets, liquid or something else?

It’s best to take undecenoic acid in tablet form that has caprylic acid powder and betaine HCL mixed in with it.

I’m not a fan of these small gel capsules with caprylic or undecenoic acid in them. I don’t find them nearly as effective as the dried powder form of these acids.

Choose a tablet vs a cellulose capsule product.

When you select a tablet, make sure that it’s 
sustained release. Sustained release means when you swallow this tablet, your digestive system doesn’t get access to everything immediately.

But over a period of several hours it slowly breaks down in the gut.

That way it targets all parts of your GI track. It cleanses all the yeast and bad bacteria right from your mouth and keeps working all the way through the colon and “back passage.”

Now, likely the supplements you were taking before were not sustained release. They weren’t put together by someone with decades of experience treating your specific health problem. They were likely put together by a company that’s got a 1000 other products and they pay lip service to making an anti-fungal or anti-bacterial formula.


Or they’ve just put out a undecenoic acid product or an oregano product. 

And that is expensive.

Why? Let’s say you’ve trying to hunt down products to clean up your gut. You do a comprehensive stool test and it says you’ve got a high count of Klebsiella (a type of bad bacteria) in there along with the Candida. 

You may have 2 or 3 issues in your gut that need fixing. You’re then likely to look at several separate products. And that’s going to cost you. That’s why a broad spectrum formula that has all of these ingredients in a sustained release form is the way to go.

How to choose the most effective undecenoic acid supplement?

After treating many Candida patients over the past 30 years or more, one tends to experiment and try different products out. You use and recommend what works and tend to move on from those products that give poor or average results.

Before I tell you exactly what type of undecenoic supplement you need to look for, let me tell you the absolute WORST thing you can do if you’ve got a Candida problem. And that’s go to your local doctor and get a round of antibiotics.

“But Eric, I thought I’m supposed to take antibiotics to kill off the bad bacteria & yeasts you mentioned previously.”

Antibiotics are the primary cause of Candida overgrowths.

Why do I say they’re the primary cause?

The problem with antibiotics (as you’ve probably read elsewhere) is they indiscriminately wipe out ALL the bacteria and yeast in your gut, including the beneficial ones.

What most people (including many general practitioners) don’t understand is beneficial bacteria are what PREVENT gut problems in the first place.

Good bacteria, primarily lactobacillus and bifida, are your gut’s IMMUNE SYSTEM. They’re like a defense force or a police unit. They keep the “bad guys” (bad bacteria & yeast) in check and prevent them from gaining a foothold.

Think about what would happen to a town or city if one day all the police disappeared.

The criminals would move in and take over.

And that’s exactly what’s happened in your gut. When you take a course of antibiotics, you're wiping out everything – the criminals AND the police. This opens doors for more bad bacteria and more yeast to get in and wreak havoc.

Instead you want something that ONLY targets the “bad guys” and doesn’t harm your beneficial bacteria. That's why I only use NATURAL products in my clinic. Particularly what are called broad spectrum formulas because they wipe out a wide range of different bacteria and yeast without causing collateral damage. 

Think of it like a natural antibiotic that only harms the bad stuff and leaves the good guys alone. 

Some doctors say you need to get your anti-fungals naturally from whole foods and not rely on supplements. But in fact that’s what my patients were doing for years. They were going to health food stores. They were buying organic foods.

And it wasn’t working.

They were buying a little of caprylic acid, or a little bit of betaine or a bottle of grapefruit seed extract. But no one had ever put a highly effective product together that targets a wide range of gut pathogens at the same time. 

That's why I got disappointed with the junk that was available in grocery stores. It’s different for you because if you have a problem and you buy a product, it’s either going to work or it’s not.

I treated thousands of people like you, so I got feedback all the time and felt responsible if something I told a patient to take ended up not getting them the results they wanted.

Too many supplements these days are filled with fake ingredients

This isn’t my opinion. It’s a fact. Back in 2015, the New York Attorney General Office conducted 390 tests on a wide range of supplements. They gathered bottles from the shelves of 4 major retail stores. 

These were GNC, Target, Walmart and Walgreens. They then sent the bottles over to a lab and DNA tested every tablet to see if the ingredients matched the label. And guess what they found. . .

Only 21% of the products actually had the herbs advertised on the bottle.

79% didn’t contain 
ANY of the herbs and were just full of crap like rice powder and wheat!

Here’s a screenshot of an article from CBS News reporting on it:

And it gets worse. . .

One survey done by the FDA found 68% of the supplements tested
didn’t even have the MAIN INGREDIENT advertised on the bottle. For example, one “St. John’s Wort” supplement contained nothing but “senna,” a laxative that can cause anal blistering.

Imagine taking something like that when you’ve already got a gut problem.

This is why I tell patients to
avoid generic brand supplements from places like Amazon or iHerb.

The way you find good supplements is by asking “Where did this product come from? Where did the company get the raw materials? What kind of research has gone into this product?”

Did the ingredients come from China?

Was the product formulated by a person who’s an expert on it? Has it been tested and proven to work on your specific problem? Do they provide extensive education about dosage or the best way to use that product?

That’s why in 2013 I set out to create my own formulations to MY standards. The first product I created was called
CanXida Remove. CanXida Remove is an advanced 12 ingredient anti-fungal, anti-bacterial and anti-parasite formula based on nearly 33 years of research working with 60,000 gut disorder patients at my New Zealand clinic or via Skype.

It is the only formula of its kind & is in my opinion the most effective Candida product currently available. 

It contains high-grade undecenoic acid in sustained release form.

Since then I've also made a probiotic designed specifically for gut disorder patients. 

I’m not going to go too in-depth into it here because this page isn’t about selling supplements. You can learn more about CanXida by watching the video below or by visiting

Whatever supplement you go with, make sure it’s high quality. Go with a broad spectrum formula made by someone with experience. Pick a supplement that doesn’t have just caprylic acid, undecenoic acid and betaine HCL in there but also things like grapefruit seed extract, standardized garlic, neen, clove, and oregano.

Be careful with what I call "designer" supplements. Even formulas like SF722 by Thorne Research (which is a high grade undecenoic acid product). These supplements are great for some people but they're very expensive. 

They only have one ingredient. They don't have any caprylic acid, betaine HCL, or grapefruit seed extract in them. They don't target other yeast strains or any of the bad bacteria Candida teams up with. 

They're good for Candida Albicans but they don't do much against other strains like Candida topicicalis, Candida krusei or the other yeasts you might have such as Aspergillus, Trichsporon, and Rhodotorula. 

It's very expensive to make your own anti-fungal, anti-bacterial supplement stack. Trust me, I've seen many patients attempt to do it and they often end up spending thousands of dollars.

Go with a formula that uses standardized ingredients

Standardization means that each time you take this supplement, you're getting a consistent therapeutic dose. It doesn't vary in potency from batch to batch as is often the case in non-standardized supplements. It's a bit like how pharmaceuticals are made.

You get the same strong therapeutic dose every time you take it.

Some practitioners tell me that undecenoic acid, grapefruit seed extract and the other ingredients I use are “old hat” and that it’s time to “upgrade.” These opinions come from dietary supplement companies who convince their customers (the healthcare professionals) that the most effective products are the latest ones they release every year.

I'm not a fan of this approach. 

Be sure to check out my YouTube channel. I’ve got over 1,500 free videos on there now all on Candida & virtually every other gut related disorder out there. Take a look because I think you’ll get a lot out of them.


1. Systematic review of topical treatments for fungal infections of the skin and nails of the feet.

2. Antimicrobial properties of 1‐monoacylglycerols prepared from undecanoic (C11: 0) and undecenoic (C11: 1) acid.

3. Effect of zinc undecylenates on plant pathogenic fungi.

4. Effect of pH on the antifungal activity of undecylenic acid and its calcium salt.

5. Fungal infections of the folds (intertriginous areas).

Before You Leave, Click Below To Grab Your Free Copy of My Candida Crusher Shopping List PDF  

Say Goodbye to Embarrassing 

Yeast Infection Symptoms

Learn the 3 stages of the gut-restoring 

diet, what foods to eat & avoid, how to 

pick out supplements and lots more.

Click below to grab your free in-depth candida

cleanse guide & start the journey to recovery.

Say Goodbye to Embarrassing 

Yeast Infection Symptoms

Learn the 3 stages of the gut-restoring 

diet, what foods to eat & avoid, how to 

pick out supplements and lots more.

Click below to grab your free in-depth candida

cleanse guide & start the journey to recovery.

Say Goodbye to Embarrassing Yeast Infection Symptoms

Learn the 3 stages of the gut-restoring diet, what foods to eat & avoid, how to pick out supplements and lots more.

Click below to grab your free in-depth candida cleanse guide & start the journey to recovery.

© All material is copyright protected 2011-2020 YeastInfection.Org


Disclaimer: All material provided on the web site is provided for informational or educational purposes only. No content is intended to be a substitute for professional medical advice, diagnosis or treatment. Consult your physician regarding the applicability of any opinions or recommendations with respect to your symptoms or medical condition.


About Us | Contact Me | FAQ | Testimonials | DMCA Notice | Terms & Conditions | Disclaimer | Privacy Policy