Winter is here, and spending more time indoors means we increase our exposure to bugs, toxins and other antigens that may work their way into the GI tract and cause health woes. Alongside reinforcing healthy lifestyle habits, we as practitioners are compelled to offer the most comprehensive protection to our patients, which includes supporting a healthy gut epithelium.


Importance of the Gut Barrier

Also known as the body’s “second skin,” the intestinal epithelium is a remarkable barrier that provides protection from harmful substances. As the single-cell layer lining of both the small and large intestine, it selectively allows nutrients to pass through while also restricting the passage of potentially harmful substances from the GI tract into the bloodstream. Paired with a healthy mucous layer, it is a critical doorway between the inside of the body and the outside world.

When damage occurs to the epithelium, this important barrier breaks down and can invite an infection, immune activation, and eventual gut inflammation.1 Chronic inflammation from epithelial damage progresses to loosening of tight junctions and increased intestinal permeability, which is also known as leaky gut. An inflamed epithelium is not a strong gut barrier, yet a strong gut barrier is essential to a healthy GI tract and immune function.


Calm the Gut

When the gut barrier is compromised, healing strategies work best when the inflammation is first cooled off. As a first step, consider the following botanicals to calm any existing gut inflammation:

In addition to such potent botanicals, antigen binders like serum-derived bovine immunoglobulins can help remove multiple types of irritants from the gut environment, preventing their interaction with the epithelium and minimizing immune and inflammatory responses.


Soothe the Epithelium

Many herbal remedies that have mucus-like properties can aid in coating the epithelium and producing a soothing effect on an irritated gut lining:

  • Deglycyrrizinated licorice, slippery elm bark and marshmallow root are substances rich in mucilage that traditionally have been used as irritation-relieving agents to coat the gastric and intestinal linings and help maintain normal inflammatory balance.
  • Mastic is a tree resin that has historically been used as a protective factor for the gut lining, and it aids in digestion.
  • Aloe vera is a novel plant recognized for its soothing, mucous-like properties that physically coats damaged areas of the gut lining, blocking the ability of pathogens to adhere to exposed areas.


Strengthen the Barrier

Last but not least, repair and reinforce the epithelial barrier with key nutritional support:

  • Glutamine directly supports the growth of intestinal cells as a main source of fuel. Enterocytes use this essential amino acid to help maintain health of the mucosa, especially when the body is under inflammatory stress.6
  • Zinc carnosine stabilizes the epithelial lining of the stomach and small intestine, directly supporting mucosal healing and tissue regrowth by stimulating the migration and growth of cells.
  • Vitamin D helps tighten gap junctions in the intestinal lining and protect the body from foreign substances, and it has natural anti-inflammatory properties.

In addition to these strategies, a healthy microbiome is essential for a fully functioning mucosal barrier. Polyphenols (in the form of punicalagin, hesperidin and naringin) can act as non-fiber prebiotics and feed probiotic bacteria in the gut to help support microbial number and diversity. In this process, they produce short-chain fatty acids that nourish and provide energy to epithelial cells, keeping them healthy and strong.



Although it might sound cliché, patients may need to be reminded to watch what they eat. Many common foods can be a problem for gut-sensitive individuals and cause serious damage to the gut barrier. For example, foods with gliadin have been linked to loosening of tight junctions in the epithelium.7 Targeted enzymes that rapidly and efficiently break down gluten proteins can add an extra layer of protection for the gut barrier.


The Bottom Line

Practitioners should look to nutritional strategies to help calm, soothe and strengthen the epithelial barrier. Such targeted nutritional supplementation is essential to restore and maintain gut barrier integrity and ensure properly functioning protection from the outside world.





Joseph Ornelas, PhD, DC holds a PhD from University of Illinois with concentration in Health Economics, an MA degree in Public Policy from the Harris School at the University of Chicago, an MS degree in Health Systems Management from Rush University, and a DC degree from National University of Health Sciences. As a licensed provider and health economist, Dr. Ornelas has published numerous evidence-based clinical practice guidelines, helping to improve quality standards of care and provide value for health care practitioners across several specialty areas.




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