The difference between Gut and Psychology Syndrome and Gut and Physiology Syndrome

Dr. Natasha Campbell-McBride initially saw autistic spectrum disorders in her practice, but the more children she saw, the more it became clear that other epidemics were emerging. Rather than trying to fit a child into any specific diagnostic box, she needed a name for the underlying disorder which originates in the gut and manifests itself in many conditions and disorders. She proposed the name Gut and Psychology Syndrome (GAPS) or GAP Syndrome. Children with GAP Syndrome often fall into “the gap” in our medical knowledge.

The difference between Gut and Physiology Syndrome and Gut and Psychology Syndrome is that the symptoms of Gut and Psychology Syndrome can be any symptom that the brain can produce, such as memory lapse, emotional symptoms, mood alterations, learning, behavioral and social problems while the symptoms of Gut and Physiology Syndrome can be any symptom the rest of the body organs can produce such as digestive problems, fatigue, muscle weakness, pain and ache in bones, joints, and muscles, neurological problems, headaches, urinary problems, etc.

Gut and Physiology Syndrome and Gut and Psychology Syndrome occur as a result of gut dysbiosis. What is gut dysbiosis? Gut dysbiosis, also known as “leaky gut”, begins when the bacteria or “flora” in your gut become unbalanced between beneficial bacteria and pathogenic or “opportunistic” microbes.

To take a step back, the human body has this mass of bacteria in the gut which we call the microbiome. There are 3 to 5 pounds of microbes there, and 90% of all cells in the human body are this gut flora. This means that the remaining 10% is the rest of your body, a shell for this habitat, so to speak.

This flora should be a balance of beneficial microbes coexisting in a highly organized micro-world of other microbes, a diverse community living together in a symbiotic relationship. They are there for the appropriate digestion and absorption of food, immune function, and hormonal balance, just to name a few functions.

Unfortunately, we are responsible for creating an imbalance in our gut, for example by taking antibiotics or eating processed foods which kill many species of bacteria in our gut. The beneficial bacteria controlling many fungi, viruses and others then become out of control. When the balance is broken and the harmony is gone, the opportunistic bacteria grow out of proportion and have the ability to cause disease. This is what happens in the GAPS person. They have an unbalanced abnormal microbial community living in their digestive system.

The digestive process relies heavily on the balanced state of our gut flora for the proper digestion and appropriate absorption of food. When the gut flora is abnormal, digestive processes become disrupted where we are unable to break down the food properly, unable to absorb it properly, and start developing multiple nutritional deficiencies.

Gut dysbiosis, or “leaky gut”, starts when the overgrowth of opportunistic bacteria damages the integrity of the gut wall. The gut wall becomes porous and leaky with holes of different sizes. As a result of the gut wall’s enterocytes damage, the food doesn’t have a chance to be digested properly, with most proteins absorbed partially broken down and undigested. As a result, the immune system finds them in the bloodstream, doesn’t recognize these particles, and attacks them by attaching various immune complexes and creating very large molecules in the bloodstream. These molecules travel around the body and cause diseases in whatever tissue they get to. Every GAPS person has this to a certain degree.

The unbalanced group of pathogenic microbes also create toxins. These toxins are absorbed through the damaged gut wall, get into the blood, get into the lymph, and get distributed all over the body causing symptoms and disease.

When this river of toxins gets in the brain, it impairs the brain function causing Gut and Psychology Syndrome. Conditions seen in the children with Gut and Psychology Syndrome include: autism, ADHD/ADD, epilepsy, dyslexia, dyspraxia, and learning, behavioral and social problems. Children’s abnormal gut flora is acquired from the parents. This abnormal gut flora damages the integrity of the child’s gut wall and turns the child into a GAPS child. Conditions seen in adults include: substance abuse, depression, eating disorders, OCD, manic-depressive, epilepsy, and schizophrenia.

Gut and Psychology Syndrome conditions are about the brain. When this toxic river gets into other organs in the body, it causes Gut and Physiology Syndrome. Gut and Physiology Syndrome disorders include all digestive disorders such as IBS, IBD, gastritis, colitis, celiac disease, etc. and are always present with any Gut and Psychology Syndrome condition.

Autoimmunity also falls under Gut and Physiology Syndrome. Every degenerative chronic illness has an autoimmune component. Since 85% of our immune system is located in the gut wall, it is therefore understood that autoimmunity is born in the gut. Autoimmune conditions include multiple sclerosis, rheumatoid arthritis, osteoarthritis, diabetes type 1, lupus, psoriasis, etc.

Gut and Physiology disorders also include ME, fibromyalgia, chronic fatigue, allergies, asthma, eczema, endocrine disorders, migraines, neurological conditions, and food intolerances.

As the human body is one entity functioning as a whole, these two GAP Syndromes occur and will always overlap each other as a result of gut dysbiosis.


Campbell-McBride, Natasha. GAPS Coach Training Portal. Module 1: Lecture Video: Introduction to GAPS In-Depth

Campbell-McBride, Natasha. Gut and Psychology Syndrome. Medinform Publishing, 2012.

Mihaly, Amy. Notes from a GAPS Practitioner: Using Diet to Unlock the Body’s Healing Secrets. What If? Publishing, 2016.