Oil of oregano contains active ingredients with antifungal, antibacterial, anti-inflammatory and antioxidant properties.
The oil can provide a nudge to balance the bacteria and fungus in your gut, helping to clear out pathogens (bad microbes), such as Candida.
It’s recommended to use oregano oil and other herbal antimicrobials as needed for chronic health issues after making diet changes and beginning probiotics.
You probably already have a jar of dried oregano in your kitchen cupboard or enjoy this fresh Greek herb in a delicious oregano pesto, or sprinkled into some other Mediterranean-inspired dish.
But apart from its culinary uses, the oregano plant — specifically oil of oregano, extracted from the leaves — has some important health benefits that can help to cleanse and restore balance and wellness to your gut. In turn, this can help with gut-related inflammatory and autoimmune conditions (including brain fog, fatigue, and colitis).
What Is Oregano Oil?
The oregano herb, Origanum vulgare L, is part of the lamiaceae family, which mint and marjoram are also part of. Oregano was originally grown in Greece and has known antioxidant activity and antimicrobial properties [1 Trusted SourcePubMedGo to source].
Oregano oil is extracted from oregano leaves. Its chemical composition includes a higher concentration of active ingredients than the whole herb.
The two main active ingredients (both part of the phenol family of antioxidants) in Origanum vulgare L oil are:
Rosmarinic acid is a third helpful ingredient in oregano oil.
A reputable, science-based oregano oil product will have standardized levels of active ingredients. The label should state a guaranteed quantity of thymol and carvacrol.
Oregano Essential Oil vs. Oil of Oregano
It’s worth mentioning that an oregano essential oil sold for purposes like aromatherapy is different from herbal oil of oregano, and the essential oil should not be consumed internally.
Oregano essential oil is generally used after being dispersed in a carrier oil, such as coconut oil or olive oil. It is then used for an aromatherapy massage or applied topically to treat skin conditions.
Health Benefits of Oregano Oil
Oregano has a long history of use as a traditional herbal medicine in humans. More “in vivo” studies (in living organisms) are needed, but lab and test tube (in vitro) studies suggest it can be helpful for:
The strong antimicrobial effects of oregano oil can help shift chronic gut-related symptoms.
For background, many symptoms and conditions such as colitis, thyroid issues, and general brain fog and fatigue could start in the gut. They can be the result of imbalances and lack of diversity in gut bacteria (gut dysbiosis), small intestine bacterial overgrowth (SIBO), or fungal or parasitic infections [10, 11, 12].
The important benefit oil of oregano can bring to gut health is its broad antimicrobial spectrum effect. This can help cleanse the intestines and clear out any remaining bacterial infections, overgrowths, or fungal infections.
Lingering pathogens or bacterial imbalances could include:
Bacterial overgrowths such as SIBO
H. pylori (which can cause stomach inflammation and ulcers)
The Science Behind Oregano Oil and Gut Health
Scientific literature reveals that extracts of oregano herb are antimicrobial, antiviral, and liver-protective. They also have analgesic (pain relieving) actions, and anti-inflammatory properties [13 Trusted SourcePubMedGo to source].
Specifically, this is how oregano oil and its active ingredients have been shown to help cleanse and rebalance the gut:
Inhibits growth of pathogens: Carvacrol has antibacterial properties. It inhibits the growth of food-borne pathogens, including E. coli, Salmonella, and B. cereus [14 Trusted SourcePubMedGo to source].
Inhibits biofilms: In animal studies, carvacrol also works against fungi and inhibits biofilms (gooey substances made by microbes that make them resistant to destruction), such as those made by Candida [14 Trusted SourcePubMedGo to source].
Reduces gut inflammation and damage: A 2017 literature review showed that thymol can be effective at reducing gut inflammation, stimulating digestive enzymes, reducing ulcers, and inhibiting gastric mucosal injury (again in animal studies) [15 Trusted SourcePubMedGo to source].
Has antioxidant properties: Rosmarinic acid in oregano oil has antioxidant properties. Antioxidants stop harmful free radicals from damaging cells [16 Trusted SourcePubMedGo to source].
Helps get rid of parasites: In one small study, 14 patients with chronic GI complaints and fatigue were found to have fecal parasites. Six weeks of daily oregano oil eliminated the parasites in 13 of those individuals [17 Trusted SourcePubMedGo to source].
When to Use Antimicrobials
But before you jump right in with oil of oregano, let’s look at where it should come in a balanced approach to healing your gut.
Check the flowchart below, and you’ll see that oregano — an antimicrobial — features as the third step (“remove”) in my eight step protocol for pursuing troublesome symptoms being driven by a problem in your gut.
In a gut healing program, it generally makes the most sense to tackle your diet first, followed by a regimen of probiotics to help balance your gut. There’s good scientific evidence and treatment guidelines from around the world to support this [18 Trusted SourcePubMedGo to source, 19 Trusted SourcePubMedGo to source].
If these two steps aren’t effective, herbal antimicrobials like oregano oil can be added as the next part of your gut healing journey.
Step 1: Reset Your Diet
To get started with moving towards a healthier gut, I recommend a gut healing elimination diet designed to:
Reduce or remove foods that may irritate your gut lining or feed imbalanced gut bacteria.
Heal and seal intestinal permeability (a leaky gut)
Feed your good gut bacteria
Help you understand which foods are triggering your symptoms
The Paleo diet is the simplest diet I recommend trying first as a framework for your elimination diet, as it is a well-rounded diet that has been shown to reduce inflammation by minimizing exposure to foods that may provoke an immune response [20 Trusted SourcePubMedGo to source, 21 Trusted SourcePubMedGo to source]. These include sugars, unhealthy fats, chemical additives, and common problem foods like dairy, gluten, and soy.
Let’s imagine that after you’ve completed the above two steps, some stubborn symptoms remain.
This is now a good time to introduce a microbial agent like oil of oregano into your treatment regimen.
Oil of oregano can give a significant step up in symptom relief for many people. Introducing this antimicrobial can help to lift your lingering GI issues, brain fog and fatigue.
Taking a Cautious Approach
When you first start microbials, your body can react in a range of different ways. Be prepared for a potential short-term worsening of symptoms due to “die-off.”
Die-off may temporarily lead to:
On the plus side, die-off symptoms are a good sign that an antimicrobial like oregano is working.
However, longer term flare-ups when you introduce oregano oil or another antimicrobial may mean it doesn’t suit you, or you may need a lower dose.
Other herbal antimicrobial agents that may work for you instead include artemisinin and berberine. It’s definitely worth exploring a few different antimicrobials to find something that works for you.
Oregano and oregano oil are “generally recognized as safe” (GRAS) as food ingredients by the U.S. Food and Drug Administration (FDA) [30 Trusted SourcePubMedGo to source]. However, you should always follow medical advice given to you by your doctor.
If you are breastfeeding, taking higher oregano oil levels higher than what you’d reasonably expect to consume from food is not recommended.
Antimicrobial resistance is when bacteria, viruses, fungi, or parasites change over time so their susceptibility to being destroyed by a pharmaceutical or natural antibiotic agent decreases.
Antibiotic resistance is a public health concern, as it increases the difficulty of treating infections and raises the risk of disease spread and serious illness . Being responsible for our own health and others means we should not overuse antimicrobials of any type.
That said, herbal compounds like oregano oil are less likely to contribute to antibiotic resistance than pharmaceutical drugs. This is because herbal compounds have a broad-acting pharmacology, enabling control of pharmaceutical-resistant organisms [32 Trusted SourcePubMedGo to source].
In other words, while bacteria and pathogens may be able to develop resistance to pharmaceutical drugs that essentially act in one specific way, they’re generally less likely to be able to develop resistance to herbal compounds, which act in multiple different ways.
Pulling It All Together
Navigating your way out of distressing gut-related symptoms can be problematic, and it can be disheartening if overhauling your diet and taking probiotics don’t have the desired effects.
This is where taking antimicrobials can be really useful, and oil of oregano is one of the most helpful options.
It can have powerful gut cleansing effects that for some people can bring greater relief than just diet and probiotics alone.
If you have further questions after reading this article, consider scheduling a virtual or in-person consultation at our functional medicine center, or read more about my eight step protocol for restoring your digestive system to health in Healthy Gut, Healthy You.
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