Well, after a long day of filing (4 hours actually), I was busily listening and taking notes from presentations in the Digestion Sessions and Autoimmune Summit.

One of the themes of these presentations was the role that stealth infections had in the manifestation of autoimmunity and digestive disorders. Specifically, a key concept discussed was molecular mimicry. (1) This occurs when a substance, which could be a toxin, infective agent, or a food antigen, enters into the bloodstream and interacts with various cells in our immune system. If the immune system recognizes the protein structure of the invader as harmful, it can become overzealous toward this “dangerous stranger.” As a result, own tissues, which appear similar to their protein structure, will be tagged and destroyed.

Other ways infections can induce autoimmunity are through inflammatory mediators (cytokines) and signaling pathways which deregulate our immune response, direct damage to the cell receptors that interact with the immune system cells (MHC), complex switching of receptor mechanisms on immune cells, and other complex mechanisms including interaction with the microbiome. (1-2)

Did I lose ya’?


This means that one of the major ways we can protect our immune and digestive systems is to remove offending critters. I have written in the past about how pathogens cannot survive in the presence of various essential oils. I have also written about how they can modulate our gut microbiome and protect the beneficial microorganisms that positively regulate our immune response.

This means genuine essential oils could be a means to support our immune system and protect it from reacting negatively to foreign invaders. Furthermore, due to the fact that many oils act as antioxidants, they can also modulate the “cleaning up” of worn out tissues and cellular debris.

Below are some of my recent findings on the power of using essential oils to make our bodies inhospitable to foreign critters and creepy crawlies.


Eucalyptus Oil

I feel bad now for ignoring my eucalyptus oil friends. Here’s a recent abstract of the review of some of its mechanisms that I got lost in while cross-referencing its references for an hour on my plane ride back from training. The review included mostly in vitro and in vivo trials, but also some human studies.

Eucalyptus oil (EO) and its major component, 1,8-cineole, have antimicrobial effects against many bacteria, including Mycobacterium tuberculosis and methicillin-resistant Staphylococcus aureus (MRSA), viruses, and fungi (including Candida). Surprisingly for an antimicrobial substance, there are also immune-stimulatory, anti-inflammatory, antioxidant, analgesic, and spasmolytic effects. Of the white blood cells, monocytes and macrophages are most affected, especially with increased phagocytic activity. Application by either vapor inhalation or oral route provides benefit for both purulent and non-purulent respiratory problems, such as bronchitis, asthma, and chronic obstructive pulmonary disease (COPD). There is a long history of folk usage with a good safety record. More recently, the biochemical details behind these effects have been clarified. Although other plant oils may be more microbiologically active, the safety of moderate doses of EO and its broad-spectrum antimicrobial action make it an attractive alternative to pharmaceuticals. EO has also been shown to offset the myelotoxicity of one chemotherapy agent. Whether this is a general attribute that does not decrease the benefit of chemotherapy remains to be determined. This article also provides instruction on how to assemble inexpensive devices for vapor inhalation. (3)

(Note: use cautiously in pregnancy and epilepsy because it’s pretty strong! There was also one report of moderate toxicity with swallowing 7.5 ml at once- ½ of a bottle!)



Tea Tree Oil (TTO) – Melaleuca alternifolia

An oil with similar terpenoid content as eucalyptus oil (except it has more terpinen-4-ol rather than 1,8-cineole), TTO is famous for its powerful effects. This abstract reviewed some of the broad spectrum killing power of various critters and applications for TTO with skin infections:

Tea tree oil (TTO) is an essential oil, steam-distilled from the Australian native plant, Melaleuca alternifolia. It has a minimum content of terpinen-4-ol and a maximum content of 1, 8-cineole. Terpinen-4-ol is a major TTO component which exhibits strong antimicrobial and anti-inflammatory properties. Tea tree oil exerts antioxidant activity and has been reported to have broad-spectrum antimicrobial activity against bacterial, viral, fungal, and protozoal infections affecting skin and mucosa. Several studies have suggested the uses of TTO for the treatment of acne vulgaris, seborrheic dermatitis, and chronic gingivitis. It also accelerates the wound healing process and exhibits anti-skin cancer activity. This review opens up new horizons for dermatologists in the use of this herbal agent. (4)

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Oregano’s Effect on Murine Norovirus in Cell Lines:

Oregano was highlighted in my training and in the seminars I’ve been listening to. So, I decided to investigate a little more. Here’s one cell culture study:

AIMS: To investigate the antiviral efficacy of oregano oil and its primary active component, carvacrol, against the nonenveloped murine norovirus (MNV), a human norovirus surrogate.

METHODS AND RESULTS: Along with an observed loss in cell culture infectivity, the antiviral mechanisms of action were determined in side-by-side experiments including a cell-binding assay, an RNase I protection assay and transmission electron microscopy (TEM). Both antimicrobials produced statistically significant reductions (P ? 0·05) in virus infectivity within 15 min of exposure (c. 1·0-log10). Despite this, the MNV infectivity remained stable with increasing time exposure to oregano oil (1·07-log10 after 24 h), while carvacrol was far more effective, producing up to 3·87-log10 reductions within 1 h. Based on the RNase I protection assay, both antimicrobials appeared to act directly upon the virus capsid and subsequently the RNA. Under TEM, the capsids enlarged from ?35 nm in diameter to up to 75 nm following treatment with oregano oil and up to 800 nm with carvacrol; with greater expansion, capsid disintegration could be observed. Virus adsorption to host cells did not appear to be affected by either antimicrobial.

CONCLUSIONS: Our results demonstrate that carvacrol is effective in inactivating MNV within 1 h of exposure by acting directly on the viral capsid and subsequently the RNA.


This study provides novel findings on the antiviral properties of oregano oil and carvacrol against MNV and demonstrates the potential of carvacrol as a natural food and surface (fomite) sanitizer to control human norovirus. (5)


These are just some highlighted oils, I invite you to explore how many others can also be used to effectively support our immune system and make critters unwelcome in our bodies.

You can also read here for other aspects to explore for optimal gut and immune function.



(1) Oldstone, M. Molecular mimicry and immune-mediated diseases.1998. The FASEB Journal. 12(13): 1255-1265.

(2) Molecular Mimicry as a Mechanism of Autoimmune Disease. Clin Rev Allergy Immunol. Feb 2012; 42(1): 102–111. doi: 10.1007/s12016-011-8294-7

(3) Sadlon, AE, Lamson, DW. Immune-modifying and antimicrobial effects of Eucalyptus oil and simple inhalation devices. Altern Med Rev. 2010 Apr;15(1):33-47. PMID: 20359267

(4) Pazyar N1, Yaghoobi R, Bagherani N, Kazerouni A. A review of applications of tea tree oil in dermatology. Int J Dermatol. 2013 Jul;52(7):784-90. doi: 10.1111/j.1365-4632.2012.05654.x.

(5) Gilling DH1, Kitajima M, Torrey JR, Bright KR. Antiviral efficacy and mechanisms of action of oregano essential oil and its primary component carvacrol against murine norovirus. J Appl Microbiol. 2014 May;116(5):1149-63. doi: 10.1111/jam.12453. Epub 2014 Feb 12. (5)

More info on Oregano: Oregano:


Disclaimer: This information is applicable ONLY for therapeutic, Grade A essential oils. This information DOES NOT apply to essential oils that have not been AFNOR and ISO standardized. There is no quality control in the United States and oils labeled as “100% pure” need only contain 5% of the actual oil. The rest of the bottle can be filled with fillers and sometimes toxic ingredients that can irritate the skin. Please check the original study for the source of the herb or essential oil. This post is not specific for any company.

This information is for information purposes only and is not intended to diagnose, treat, or prescribe for any illness.

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