Lab Testing to Investigate Leaky Gut

LAB MARKERS	WHAT IT MEANS
Zonulin • Blood (serum) • Stool	High levels are associated with leaky gut. High levels are found in conditions such as celiac disease.
Lactulose-Mannitol • Urine	Lactulose and mannitol are sugars absorbed in the intestines. After drinking a liquid containing these sugars, your urine is tested to see how much has "leaked" from your intestines into your bloodstream. Lactulose is a larger molecule that should not pass through a healthy intestinal barrier. It should be low. Mannitol is a smaller molecule that is more easily absorbed. You would expect mannitol to show up. A high ratio of lactulose to mannitol indicates a leaky gut.
Calprotectin • Blood (serum) • Stool	High levels are associated with intestinal inflammation and leaky gut.
Fecal Long-Chain Fatty Acids • Stool	Fecal long-chain fatty acids need to be absorbed in the gut through the intestinal lining. Triglycerides indicate fat malabsorption and issues with a leaky gut.
Microbiome Testing • Feces	Imbalances in gut bacteria (gut dysbiosis), especially lipopolysaccharides (LPS) and histamine-producing bacteria are often associated with leaky gut.
Lipopolysaccharides (LPS) • Stool • Blood (serum)	LPS is highly inflammatory and damages the intestinal lining. Histamine increases the permeability of barriers such as the intestinal barrier.

   

ADDITIONAL TESTS

LABORATORY MARKERS	WHAT IT MEANS
Hydrogen and Methane Breath Test	Your breath can be used to screen for SIBO and carbohydrate malabsorption, which can both contribute significantly to a leaky gut. Its non-invasive nature makes it an affordable option for those with digestive issues.
Food allergies or sensitivities	Identifies specific food allergies or sensitivities that may contribute to inflammation and intestinal permeability.
Biopsy analysis	During an endoscopy, small pieces of tissue can be collected to help doctors better understand and diagnose digestive system problems. This helps them determine the exact problem and rule out more serious conditions.