What Is the Microbiome?
The scientific literature claims that the human microbiome should be considered an organ or even a “super-organism.” Discovered as recently as the 1990s, the microbiome is now known to have a powerful impact on our human health. The term “microbiome” is referred to by experts as the collection of the genomes of microbes in a particular ecosystem. The term “microbiota” is referred to as the collection of organisms.
The entire digestive tract is a living ecological community of microorganisms – over 100 trillion bacteria – which we call the microbiome. What is even more astonishing is that over 70% of our immune system is influenced and shaped by the enteric bacteria or gut flora found in the microbiome of the gastrointestinal tract. There is an intrinsic, complex interaction among the gut, the immune system, and even the nervous system, which includes our brains!
Gut-Brain-Immune System
You might have heard the terms “gut-brain-connection”, “the second brain”, or the “gut-brain-axis“. These all refer to the communication between the central and enteric (gut) nervous system – the connection between the emotional and cognitive centers of the brain and the gastrointestinal system. The gut and brain communicate bi-directionally, AND they also communicate with the immune system. Neurons and their chemical messengers called neurotransmitters are found in the brain and they also exist in the gut, or enteric nervous system, a vast mesh like matrix of nerves housed in the intestines. Half of the body’s dopamine and 95% percent of the body’s serotonin are actually produced in the gut!
The gut and the brain both rely on an autonomic (or automatic) nervous system (ANS). The system that governs the gut is usually referred to as the enteric nervous system (ENS). When the ANS is operating normally and senses danger or stress, it activates a sympathetic state that we often call “fight-flight-or-freeze.” When there is no, or low, stress in a body, it can enter the parasympathetic, or “rest-and-digest” state. Our immune system must keep in step with the demands of the changing landscape of stress and safety in our bodies too. Along with the nervous system, the immune system runs surveillance to protect us from harm while allowing our bodies to continue to function, grow, repair, and ultimately thrive.
Because of the intimate, co-dependent relationship between the gut inhabitants (a so-called super organism) and other body systems, when there are alterations in the make-up or functioning of the microbiome, there are not merely intestinal consequences. Changes in the microbiome also impact our brains and immune system. Scientific research is repeatedly showing us that LOW bacterial diversity in the gut is associated with worse health outcomes (see Sources & References, below). Nowhere is this more obvious than in children with autism spectrum disorders who express behavioral abnormalities, cognitive deficits, developmental delays, sensory issues, immune dysregulation, typically have signs or symptoms of poor gut health AND poor microbiome diversity.
What’s in the Gut – a Diverse Microbiome or Dysbiosis?
Derrick MacFabe MD, PhD, a Canadian researcher, was actually the first researcher to scientifically prove this gut-brain-immune connection through mouse studies. He discovered how gut bacteria can alter behaviors in children with autism. Dr. MacFabe found that children with autism had a history of antibiotic exposure or hospitalization, gastrointestinal symptoms, abnormal food cravings and unique intestinal bacterial populations that were related to the severity of their symptoms.
His research on the role of enteric short-chain fatty acid fermentation products, in particular one strain called proprionic acid (PPA), a toxic metabolite of Clostridia difficile (C. diff), was found in the gastrointestinal tract of children with autism. PPA is a compound of many gastrointestinal bacteria and a common food preservative. It and other metabolites of gut pathogens (colletively known as gut dysbiosis) can cause neurochemical changes that are all consistent with autism findings, such as:
- Neuroinflammation
- Oxidative stress
- Mitochondrial dysfunction
- Glutathione depletion
- Altered phospholipid/acetylcarnitine levels
The results from laboratory studies showed that rats treated with PPA developed behaviors similar to autism such as repetitive, perseverative, antisocial behaviors and seizures. Metabolites (or substances formed by) gut pathogens affect many important aspects of our bodies such as”
- Neurotransmitters
- Intracellular acidification
- Calcium release
- Fatty acid metabolism
- Immune function
- Alteration of gene expression
Environmental triggers may be part of gut dysbiosis, and it is quite clear that the role of the microbiome has an effect on metabolism, immune, mitochondrial function and gene expression in children with autism as well as those with other chronic health conditions.
Healing the Microbiome
Healing the microbiome can make many positive changes in your child, such as:
- Reducing histamine and inflammation responses
- Reducing the intensity of anxiety and depression (anger in many cases)
- Reducing the self-stimulatory behaviors
- Reducing head-banging and self-mutilating behaviors
- Reducing hand-flapping
- Reducing pacing and hyperactivity
- Reducing the number of meltdowns
- Reducing repetitive and obsessive compulsive behaviors
- Improving sleep issues
- Improving coping abilities
- Strengthening and improving the immune system
- Improving sensory processing
Better Diet for a Better Microbiome
Diet plays a big role in the elimination of gut pathogens (the harmful organisms) in the gastrointestinal tract. A typical modern-day acidic diet of refined sugars, high fructose, simple carbohydrates, gluten, casein, trans-fatty acids, fast foods with chemical preservatives, and refined foods increase gut dysbiosis in the digestive tract and affect the brain and the immune system.
If your child is eating a high carbohydrate and rich food diet, then the likelihood of gut dysbiosis is much higher. Gut dysbiosis increases acidity and can create more physical symptoms as well as behaviors. To lower levels of gut pathogens, give your child a diet rich in:
- Fermented foods and vegetables
- Kefir non-dairy yogurt
- Organic vegetables, fruits and protein
- Good quality fats
- Lots of prebiotics and probiotics
- A gut-healing diet
These will typically help heal the microbiome by alkalizing the gut and creating more butyrate in the gut which is necessary for restoring gut integrity. Other supports can be put into place to heal a gut that lacks integrity, too. Rebalancing the gut microbiota by healing the microbiome will improve the gut lining and brain function, reduce behaviors, and keep the immune system stronger.
A practitioner who is “gut literate” may want to help you lower certain pathogens before embarking on certain enriching foods. For instance, if yeast is something that is overgrown in the gut, you may want to start with healthy fats and fiber rich foods or use herbs before introducing fermented foods. To test for imbalances in the microbiome, your provider may want to order an Organic Acid Test (OAT) and/or a Comprehensive Digestive Stool Analysis.
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Resources
Books
Galland, Leo. The Effect of Intestinal Microbes on Systemic Immunity. Excerpted from Power Healing. Random House, 1998.
Lambert, Beth. A Compromised Generation: The Epidemic of Chronic Illness in America’s Children. Sentient Publications, 2010.
Sachs, Jessica Snyder. Good Germs, Bad Germs: Health and Survival in a Bacterial World. Hill and Wang, 2007.
