Zonulin is a protein modulator of intestinal tight junctions and is used to assess intestinal permeability. It can be used for assessing impaired gut barrier function for several autoimmune and metabolic conditions including celiac disease, type 1 diabetes and insulin resistance.

Zonulin is a marker of intestinal permeability, otherwise known as leaky gut. If a person has elevated Zonulin levels, the normal regulation of the tight junctions is compromised. 

Zonulin is a protein that is synthesized in intestinal cells and liver cells. It is a key biomarker for intestinal permeability and is the only regulator of intestinal permeability that is reversible.

What is intestinal permeability?

Intestinal permeability, often referred to as "leaky gut," is a condition where the lining of the small intestine becomes damaged, causing undigested food particles, toxins, and bacteria to leak through the intestinal wall into the bloodstream. Normally, the gut lining acts as a barrier, selectively allowing nutrients to pass through while keeping harmful substances out. When this barrier is compromised, it can lead to inflammation and trigger immune responses, potentially contributing to various health issues such as food sensitivities, digestive problems, and even autoimmune diseases.

Elevated antibody levels can be clinically significant — while the antibodies themselves don’t destroy anything, they do trigger an inflammatory response that can cause significant destruction of tissue and resulting symptoms. This response is not necessarily dependent on antibody levels. However, an equivocal result may mean you are just beginning to exhibit an immune reaction, so this is an important time to take measures to support the body in damping immune reactivity.