The lumen of the gastrointestinal tract is lined with a mucus layer produced primarily by specialized epithelial cells called goblet cells. This mucus layer plays a crucial role in maintaining gut health and function. It also hosts various gut microbiota species, immune system cells, and mucus components. Some microbiota species can break down mucins, one of the main glycoproteins in the mucus layer, liberating sugars such as N-acetyl-D-glucosamine.

N-acetyl-D-glucosamine is an amino acid sugar derived from glucosamine that may support many aspects of human health. NAG is a structural component of cell walls, connective tissues, and cell surfaces. For example, it is a vital building block of glycosaminoglycans, which are essential for forming the protective mucus barrier in the intestine. Because of its role in mucus production and structural integrity, NAG is important for gut health, mucus barrier support, and immune health. Additionally, it may support individuals with inflammatory bowel disease. 

One of NAGs most notable supportive roles in GI health is its role in promoting mucus barrier health in the presence of harmful bacteria, such as pathogenic and virulent strains of Escherichia coli (E. coli). One of the characteristics of E. coli is the ability to form biofilm. Biofilm formation may promote their colonization and resistance to effective GI removal. In an in vitro study, researchers investigated the effect of NAG on the biofilm formation of a specific strain of E. coli referenced as LF82 (commonly found in Crohn’s disease patients). Compared to LF82 grown in a medium alone, LF82 cells given NAG exhibited a statistically significant lower amount of biofilm formation. These observations may have significant applications for supporting IBD since biofilm formation has been observed in these populations, although further study is required to draw any clinical conclusions. 

Building on these in vitro findings, research exploring the effects of NAG in human populations provides further insight into its potential supportive features for individuals with IBD. In an open-label clinical trial, 34 adults with IBD were given 6 g/day of NAG for four weeks, with symptom scores assessed at baseline and at the study’s conclusion. Notably, 88.1% of patients (30 out of 34 patients) who were given NAG reported reduced IBD symptoms, and 58.8% (approximately 19 out of 34 patients) noted improvements in abdominal pain with a 49% reduction in symptom scores reported at the end of the study compared to baseline scores. Additionally, symptoms of diarrhea improved in approximately 21 patients. Important in individuals with IBD, significant decreases were observed in nausea, mucus discharge, and rectal bleeding. 

The researchers theorize that NAG may support mucus barrier health by promoting mucin formation. This may support the integrity of the mucosal barrier by attenuating its potential breakdown by pathogenic strains of biofilm-forming bacteria. This theory is partially supported by biopsies taken from children with IBD after they were given NAG. From the biopsies, the researchers report that the epithelial expression of mucin increased, suggesting supported mucin formation.  

Although these findings are exciting, research related to NAG's potential to support gut health and barrier integrity is still emerging. Current research indicates that NAG may support GI function and gut mucosal health by supporting mucin formation and helping the body mitigate biofilm formation, as well as a healthy immune response. 

To learn more about N-acetyl-D-glucosamine:

N-Acetyl-D-Glucosamine: A Key Player in Balanced Immune and Healthy Inflammatory Responses 

N-Acetylglucosamine and Immunometabolism

The Hidden Effects: Medications and Their Impact on Your GI Tract 

By Bri Mesenbring, MS, CNS, LDN