However, there is no scientific data in humans that a leaky gut resulting in increased intestinal permeability causes symptoms outside the gastrointestinal (GI) tract. Leaky gut syndrome is considered a theory, rather than a condition traditionally recognized by the general medical community.
Symptoms of Leaky Gut Syndrome
Symptoms of leaky gut include:
Abdominal pain Asthma Chronic joint pain Chronic muscle pain Confusion Gas Indigestion Mood swings Nervousness Frequent colds Recurrent vaginal infections Skin rashes Diarrhea Recurrent bladder infections Poor memory Shortness of breath Constipation Bloating Anxiety Irritability Fatigue
Causes
Potential causes of leaky gut syndrome include:
Chronic stressIntestinal infectionsSmall intestine bacterial overgrowthEnvironmental contaminantsExcess alcoholPoor dietNonsteroidal anti-inflammatory drugs (NSAIDs) and other medications
Alternative practitioners sometimes associate leaky gut syndrome with the following conditions:
Autoimmune disease Celiac disease Crohn’s disease Environmental illness Hives Acne Allergies Inflammatory joint disease/arthritis Intestinal infections Pancreatic insufficiency Ulcerative colitis Giardia (a parasitic intestinal infection) Chronic fatigue syndrome Eczema Psoriasis Food allergies and sensitivities Liver dysfunction Rheumatoid arthritis Irritable bowel syndrome
The lining of the intestines creates a barrier that normally allows only properly digested fats, proteins, and starches to pass through and enter the bloodstream. It allows substances to pass in several ways.
Chloride, potassium, magnesium, sodium, and free fatty acids diffuse through intestinal cells. Amino acids, fatty acids, glucose, minerals, and vitamins also cross through cells, but they do it by another mechanism called active transport.
There’s a third way that substances can pass through. The spaces in between the cells that line the intestines are typically sealed. These tight junctions are called desmosomes. When the intestinal lining becomes irritated, the junctions loosen and allow unwanted larger molecules in the intestines to pass through into the blood. The immune system sees these unwanted substances as foreign (because they aren’t usually present in the blood). This triggers an antibody reaction.
When the intestinal lining becomes further damaged, even larger substances, such as disease-causing bacteria, undigested food particles, and toxins, pass directly through the damaged cells. Again, the immune system is alerted, and antibodies and substances called cytokines are released. Cytokines alert white blood cells to fight the particles. This fight produces oxidants, which cause irritation and inflammation throughout the body.
Diagnosis
The standard test for leaky gut syndrome is the mannitol and lactulose test. Both are water-soluble molecules that the body can’t use. Mannitol is easily absorbed by people with healthy intestinal linings. Lactulose is a larger molecule and is only slightly absorbed.
For the test, a person drinks a mannitol and lactulose solution. Urine is collected for six hours, and the amount in urine reflects how much of each was absorbed by the body.
A healthy test shows high levels of mannitol and low levels of lactulose. If high levels of both molecules are found, it indicates a leaky gut condition. If low levels of both molecules are found, it indicates general malabsorption of all nutrients.
A Word From Verywell
It’s important to keep in mind that there is limited research about leaky gut syndrome. It’s also important to note that self-treating a condition and avoiding or delaying standard care may have serious consequences. If you’re experiencing any symptoms or are concerned about your health, consult your physician.
