The Role of the Microbiome in Food Allergies
DR. WEITZ'S BLOG, RATIONAL WELLNESS PODCAST
The Role of the Microbiome in Food Allergies with Dr. Tom Fabian – Rational Wellness Podcast 233
Tom Fabian, PhD speaks about the Role of the Microbiome in Food Allergies with Dr. Ben Weitz. Airdate: 11/17/21
Podcast Highlights
1:30 Food allergies vs Food sensitivities vs Food intolerances. – Food allergies are mediated by Immunoglobulin E and mast cells tend to play a role. Patients with true food allergies may have very severe reactions such as anaphylaxis and they are immediate after eating that food. Food sensitivities are typically mediated by IgG and they tend to be delayed reactions. They can also be mediated by IgM and IgA, though these are less well defined. Secretory IgA, which is reported on the GI-MAP stool test from Diagnostic Solutions, is known to play multiple roles in the gut both in terms of reacting to things thought to be threats, but also a protective role in terms of commensal bacteria in which IgA binds to these commensals and by binding to normal food antigens, it helps to reduce or prevent over-reactivity from the immune system.
7:13 A Food Intolerance is a non-immune mediated reaction to a food, such as a carbohydrate intolerance or a histamine intolerance, which can be mediated by a lack of diamine oxidase enzyme, which keeps you from breaking down histamine.
8:46 A healthy microbiome can play a role in our oral tolerance to foods that might otherwise be harmless. Our immune system has a balance of pro-inflammatory and anti-inflammatory. Immune tolerance is a mechanism by which the immune system restrains overreaction, which applies to food allergies, and involves Treg cells. There are a number of products from the microbiome that promote Treg cells that promote immune tolerance and the one that has been best studied is butyrate. Certain commensal microbes seem to be especially important. In the small intestine, the important microbes are Lactobacillus, Bifidobacterium, and Prevotella, esp. a particular species, Prevotella histicola, which has been shown to protect against food sensitivities.
15:46 Leaky Gut. If you have leaky gut or increased intestinal permeability, then you can more easily get food antigens across the epithelial lining of the gut and react with the immune cells in the intestinal mucosa. If you have overgrowth of inflammatory type bacteria, such as E. coli, Klebsiella, or Citrobacter, this can cause leaky gut. Certain microbes can modify how antigenic a protein is. Pseudomonas, which is common resident of the small intestine, can break down certain proteins, such as gluten in a way that makes it easier for the gluten to get through the leaky gut. Then the gluten doesn’t break down enough till it is broken into individual amino acids, which is the ideal situation, since amino acids usually do not cause immune reactions. It’s the larger proteins that cause immune reactions. This is one of the reasons why hydrochloric acid is so important to break down proteins and a lot of people do not have enough hydrochloric acid.
Author Tom Fabian, Ph.D., CNTP
Dr. Fabian is a leading expert on the role of the microbiome in health, immune function, chronic disease, and aging. As a translational scientist, his primary focus is on the clinical application of microbiome research in the integrative and functional medicine space. He received his PhD in molecular biology from the University of Colorado, Boulder, and has worked as a biomedical researcher in the biotechnology industry...
The opinions expressed in this presentation are the author's own. Information is provided for informational purposes only and is not meant to be a substitute for personal advice provided by a doctor or other qualified health care professional. Patients should not use the information contained herein for diagnosing a health or fitness problem or disease. Patients should always consult with a doctor or other health care professional for medical advice or information about diagnosis and treatment.