Disease and the Gut

The information presented is for general interest and is not intended as medical advice.  Please consult with your veterinarian if you have any concerns regarding the health of your pet.  Much of the information has been gathered from resources that pertain to human health because more work has been done in this area; veterinary research dealing with the connection between disease, the immune system, and gut flora is fairly recent in comparison. What is considered safe for humans is not necessarily so for non-humans.  Readers are encouraged to do their own research from reputable resources and experts. 

“All disease begins in the gut.” ~ Hippocrates, Father of Medicine

It’s no mystery that pets are suffering from many of the same illnesses that are plaguing humans.  Chronic gastrointestinal problems, autoimmune disorders (i.e. allergies, diabetes, arthritis) and problems with organs such as kidneys, liver, and thyroid are increasing in both pet and human populations. The modern North American diet, with its emphasis on processed foods high in sugars and refined flours, has been blamed for many human health problems.  What if this were true for our pets, too? Could highly processed commercial pet food be the cause of our pets’ increasingly poor health, or are there other factors beyond diet to consider?

Dr. Marilyn Sthamann from the Lakewood Animal Hospital in Regina is exploring diet’s influence on the health of the gut, its relationship to disease, and the role probiotics play.  “When I started homeopathy in my practice back in 1999,” explains Dr. Sthamann, “I remember my clients discussing with me how they took acidophilus for themselves. Today there is so much in the media about probiotics, but ten to fifteen years ago it was not mainstream. Naturopaths were talking about probiotics then and as the years went on, the vet community started talking about this and coming out with probiotic support to treat diarrhea and for use with antibiotics.  It wasn’t that they could see that probiotics were curing everything, but they saw that they could help.”

A small group of her clients with very itchy, allergic dogs began feeding a simple, raw, “whole animal” diet.  Under Dr. Sthamann’s direction, her clients supplemented the diet with digestive enzymes, Omega 3 fatty acids, and natural, freeze-dried green tripe.  The plan was to remove all the “bad stuff” and feed a diet as natural and easily digestible as possible in order to let the gut heal and allow the immune system to get back into balance. When choosing an animal protein to feed, Dr. Sthamann suggested they pick one that was new to the dog’s diet — one that the dog’s immune system would not already have antibodies for, such as rabbit, quail, or alpaca.   Some of Dr. Sthamann’s clients saw their pets’ health improved immediately, and some were even able to eat small amounts of foods that were previously a problem.  Other clients in the group saw minor improvements or no improvement.

“Healing can take a long time,” explains Dr. Sthamann, “and when some clients find it difficult to wait, especially if their pets’ symptoms are severe, I’ve had to resort to including homeopathic remedies and sometimes conventional medication.  My experience with holistic medicine is that it is wonderful — the improvements in treatment and understanding of disease — yet there are still some individuals whose systems aren’t able to heal.  There are many factors involved: a client’s ability to be patient, the condition of the patient – is there too much pathology already?  What else is happening in those instances?”  The trial is still ongoing and Dr. Sthamann looks forward to seeing more results.

This approach to health is not new.  Dr. Sidney Haas (1870 -1964) designed the Specific Carbohydrate Diet (SCD) and used it to treat hundreds of patients with Celiac Disease. After witnessing her daughter’s life-threatening digestive problems disappear from following the SCD, Dr. Elaine Gottschall (1921-2005) spent the next forty years fine-tuning the SCD while researching how food affects the body and the brain. In 1987 Gottschall published Food and the Gut Reaction: Intestinal Health Through Diet, and later editions were published as Breaking the Vicious Cycle: Intestinal Health Through Diet.  More recently, Dr. Natasha Campbell-McBride studied the link between the health of the gut and the health of the mind after her son was diagnosed with autism. Dr. Campbell-McBride modified the SCD to successfully treat her autistic son, developing the GAPS diet, which has helped many children and adults with gastrointestinal and psychological conditions.  In 2004 she published a book called Gut and Psychology Syndrome: Natural Treatment Of Autism, ADHD, Dyslexia, Dyspraxia, Depression and SchizophreniaThese doctors and their patients have shown that overall health is dependent upon a healthy gut, and a healthy gut is dependent upon healthy gut flora. Leaders in holistic veterinary medicine have been taking these ideas and applying them to the animal world.

Gut flora is responsible for many things essential to good health.  It is made up of a thick layer of microbes (i.e. bacteria, fungi, viruses, etc.) that covers the entire surface of the gut. Enterocytes (cells lining the gut) are kept functioning properly by healthy gut flora, which allow food to be digested and nutrients to be absorbed.  Gut flora produces antibiotic, anti-viral, anti-fungal, and anti-parasitic substances as well as digestive enzymes and essential vitamins (i.e. Vitamins K and B).  It protects the body from “invaders” we ingest and byproducts of digestion either by neutralizing toxins or carrying them out of the body.  Balanced gut flora keeps the gut wall healthy which prevents the contents from leaking into the bloodstream. If the gut isn’t functioning properly, the body is doomed.

Research in this area points to the idea that an unhealthy gut causes illness in this way:

1.  The gut flora gets out of balance. The bad bacteria outnumber the good bacteria (gut dysbiosis).

2.  Gut dysbiosis interferes with proper digestion and results in gastrointestinal inflammation and nutrient deficiencies. Common symptoms at this stage include gas, bloating, diarrhea, constipation, undigested food in stool, and foul-smelling stools; but individuals differ and sometimes these symptoms are minor and easily ignored.  Other symptoms can include a loss of appetite and/or the desire to eat mostly sugary and/or starchy foods.

3.  Gut dysbiosis leads to damage of the gut wall (leaky gut) allowing intestinal contents (i.e. food particles, microbes, toxins) to leak into the bloodstream.  This causes immune dysfunction (i.e. allergies, food intolerances) and increased toxicity in the body.

4. The liver and other detox pathways become overloaded. This often causes symptoms such as (but not limited to) headaches, lethargy, brain fog, pain, rashes, breathing problems, infections, incontinence, and flu-like symptoms.   This can also cause psychiatric and behavioural symptoms (mood swings, depression, aggression, learning problems, compulsive behaviours) because many of the toxins produced by the pathogens are neural toxins.

5. Autoimmunity and organ damage occur.  Depending on which organs are attacked, various symptoms that have previously “stumped” the medical professionals eventually lead to a diagnosis of a disease.  Often a patient has one main diagnosis with several symptoms of other diseases/disorders (i.e. arthritis with irritable bowel symptoms; diabetes with ADD symptoms).

There are many causes of gut dysbiosis.  A person can start life with unhealthy gut flora because each person gets his/her gut flora from the birth canal – in effect inheriting healthy or unhealthy gut flora.  Advanced age can also weaken the gut flora as can illness and disease.   But according to those studying this, the four factors that significantly weaken gut flora the most are stress, drugs such as steroids and NSAIDS (non-steroidal anti-inflammatory drugs), antibiotic use, and diet.  Vaccines are not included as a factor that weakens a body’s gut flora, but they do cause damage to the immune system when they are administered to a body whose immune system is not prepared to handle the vaccines.  This is one reason why some pets and people can handle vaccines while others cannot and become ill from them.

Stress has been widely accepted as a major factor in disease and illness in people, and it holds true for animals, too.  Stress can interfere with digestion and cause the intestinal tract to shed good bacteria.  Steroids (i.e. prednisone) and NSAIDS (i.e. aspirin, ibuprofen, naproxen) have also been implicated in upsetting the balance of bacteria in the gut (yet these are often prescribed to deal with the symptoms that are common to gut dysbiosis).

Antibiotics, by their very definition, can wreak havoc on the gut flora. They can save lives but they can lead to gut dysbiosis because they kill the good bacteria as well as the bad; unfortunately, the good bacteria are the first to be destroyed by antibiotics and are slower to repopulate than the bad bacteria.  It can take weeks to months for the good bacteria to repopulate the gut (some strains take longer than others), and during this time the bad bacteria can take over.  To make matters worse, there are other pathogens in the gut that are resistant to broad-spectrum antibiotics (i.e. Clostridia, Candida); these are normally kept under control by good bacteria but during a course of antibiotics and for weeks after, they are able to take over and are very difficult to get rid of.  Clostridia produce neurotoxins that can cause neurological and psychological problems.  Candida can cause all sorts of health problems, including inflammation and joint pain.  Like the bad bacteria, Candida love sugary, starchy foods and when the yeast digests these foods it produces a toxin called acetaldehyde.  This toxin then attaches itself to proteins in the body, collagen in particular, which triggers the body’s immune system to attack these “odd looking proteins”, resulting in migratory inflammation and pain, often in the joints.  If antibiotics are necessary, some who have studied gut flora suggest taking probiotics a few hours after each dose of antibiotic and for several weeks after the course of antibiotics is complete.  It is important to note that not all probiotic products are of good quality, and some probiotics contain ingredients and strains that some experts believe are harmful to a gut that is already severely out of balance.

Diet is the most important factor related to the health of gut flora.  There are many different species of microbes that make up the ecosystem of the gut flora, and if the diet favours certain species, these will thrive and take over.  A diet consisting mainly of sugary, starchy foods (i.e. grains, root vegetables, corn) will feed the pathogens that are present in every gut, causing them to outnumber the good bacteria.  The SCD is designed to bring the gut flora back into balance by starving the pathogens.  The diet contains no complex carbohydrates; the only carbohydrates allowed are monosaccharides because the gut absorbs them quickly and no food is sitting around waiting to be digested, feeding the pathogens.

As well, a damaged digestive system will not be able to tolerate foods that contain anti-nutrients (i.e. found in grains, including rice).  Is it any wonder that many pets (and people) do better when sugars and starches are removed from their diet?

If the gut has become too damaged, then most foods will be troublesome.  Making foods more digestible (i.e. grinding, pureeing, adding enzymes, cooking, peeling, seeding, fermenting) is essential for healing a damaged gut.  For humans, some foods that seem to be very healing to a damaged gut are high quality animal protein, bone broth, animal fat, and natural probiotic foods like sauerkraut and homemade yogurt (fermented 24 hours).  For pets, it seems a healing diet is a species-appropriate one based on quality protein, bone, fat, organ meats, and tripe (for its probiotic benefits as well as its nutrients) and a small amount of steamed/pureed/juiced non-starchy veggies (mostly leafy greens).

There are differing opinions about some of the finer details regarding how to heal the gut and put the gut flora back into balance, but there is agreement in the overall approach: modify the diet to a) starve the bad bacteria; b) help the damaged gut heal, and c) repopulate the gut with good bacteria.  Digestive enzymes are sometimes recommended as a way to make food more digestible, and in some cases where there are serious nutritional deficiencies, natural supplements (i.e. essential fatty acids, except in the case of epilepsy) are recommended as long as they don’t overwork the liver or contain ingredients that irritate the gut.  It’s important to avoid foods that trigger the immune system; many foods can be gradually added back into the diet after the gut has healed.  Because yeast is so difficult to eradicate from the body, some practitioners recommend some natural anti-fungals, but only when the body is strong enough to tolerate them.

It’s also essential to reduce the patient’s toxic load by reducing the toxins in the environment and in foods.  Many caution against detoxification through any supplements or special cleanses because they are often too much for the patient in the early stages of healing; the detox pathways are too overloaded in the beginning to handle more detoxification than what happens naturally as the body heals itself.

When patients heal and get their gut flora back into balance, their symptoms greatly reduce or disappear if there hasn’t been too much damage done.  They are able to eat foods they couldn’t before and many of their allergies vanish.  It’s important to note that the healing process can be difficult because as the pathogens are starved, they release toxins that can cause very unpleasant symptoms.  These “die off” reactions can be severe so it’s essential to go slowly to reduce the intensity of the reactions.  In the human experience, there also seems to be “plateaus” every second or third month in the healing process; this can be discouraging as healing seems to stop and some symptoms return.  This approach takes time, and adults take longer than younger patients.  In humans, most patients experience noticeable healing within the first month and require about two years to heal completely.  However, it’s important to remember that each individual is different; some will never be able to eat a diet high in sugars or starches.


Breaking the Vicious Cycle: Intestinal Health Through Diet by Dr. Elaine Gottschall (2004)

“Dysbiosis: The Root Cause of Many Other Health Problems” by Dr. Karen Becker

“Eating Grains Can ‘Tear Holes’ in Your Gut” by Dr. Mercola

“Gut and Psychology Syndrome; Gut and Physiology Syndrome” presentation at Weston Price Foundation Conference “Wise Traditions London 2010”