By Kevin Lamberg
Many wholistic-minded practitioners believe optimal gastrointestinal health is the first step in maintaining and restoring the innate healing potential of the body. Sadly, chronic illness from poor lifestyle choices now make up more than 75 percent of the burden of health care costs in the United States. An increase in stress levels, excessive sugar intake and daily consumption of low-quality refined foods all contribute to the growing problem. Consequently, dietary choices can disrupt gut mucosal tissue and immune homeostasis over time. As a result, researchers are focusing more of their attention on the intestinal barrier. Thus, lifestyle modifications and therapies that cultivate optimal permeability may soon become a widely accepted standard of care in natural medicine.
The structure of the intestinal outer wall, referred to as the mucosa, functions as an absorbent unit. The small intestine is extensively folded to increase the surface area capacity for absorption. The villi that line the outer wall further increase the surface area and act as specialized units that both absorb and secrete. The villi themselves consist of a thin layer of epithelial cells that cover an inner core of blood and lymph vessels. In a healthy example, nutrients are assimilated by the absorptive cells, reach the inner core and are taken up by these blood and lymph capillaries. These cells are fused together by tight junctions so that nutrients only pass across the cells, not between. A wholesome diet made up of adequate, high-quality fruits and vegetables may play a significant role in maintaining the proper function of this system.
Gut Mucosa and Immune Health
The connection between the gut mucosa and health has not always been clear, but newly identified immune cells called innate lymphoid cells (ILCs) found in high numbers in mucosal tissue may be providing new insight. “Innate lymphoid cells are a family of immune cells that selectively accumulate in mucosal tissues serving as sentinels at the vanguard of host protective immunity.” These mucosal cells respond to environmental influences that include diet and can change and remodel immune function. However, they may be implicated as cellular mediators in immune-mediated pathology. Ultimately, an altered epithelial barrier function may contribute to intestinal inflammation and the “sounding” of the immune alarm. “Dysregulation of the epithelial barrier function can lead to increased intestinal permeability and bacterial translocation across the intestinal mucosa, which contributes to local and systemic immune activation.”
Lately, there has been growing interest in immunomodulatory nutrients like L-Glutamine that may regulate host immunity, the inflammatory response and thereby support the intestinal barrier.* Researchers became interested in studying individuals who are subjected to high-intensity exercise because it has been shown to increase gut permeability. A recent survey on L-Glutamine described its role in reducing exercise-induced permeability by inhibiting the NF-kB pro-inflammatory pathway in human peripheral blood mononuclear cells.* By providing a seven-day dosing plan during intense exercise, the epithelial tight junction protein complex in the gastrointestinal tract was supported, encouraging optimal permeability.*
Sustamine, a revolutionary dipeptide that combines pure L-Glutamine and L-Alanine adds a groundbreaking option for supporting gut health.* Clinically tested, Sustamine® is produced through a novel enzymatic process that creates a unique, readily absorbed dipeptide.* Since a dipeptide is simply a bonded chain of two amino acids rather than a more complex protein, the body can quickly transport it into intestinal cells. A study published in the Journal of the International Society of Sports Nutrition demonstrated that the dipeptide had a positive impact on electrolyte absorption and improved transport channels in the GI tract.*
Intestinal Microflora, Fiber and Mucosa
An extremely refined diet often lacks a meaningful quantity of dietary fiber from fruits and vegetables. Therefore, supplemental sources of complex polysaccharides may be indicated. Arabinogalactan, a complex polysaccharide derived from the larch tree, is an excellent source of dietary fiber. The fermentation of carbohydrates into short-chain fatty acids by intestinal microflora is essential to maintain the health of the large intestine.* Commonly available sources of arabinogalactan in the diet include carrots, radishes, pears, and tomatoes.
Marshmallow (Althea officinalis) and slippery elm bark (Ulmus fulva) have been traditionally used to support irritated mucosa.* We now understand that the mucilaginous compounds present in both plants in high amounts account for their historical use. Both may occasionally help soothe mild aggravation of the gastric mucosa.* An in-vitro study published on marshmallow in 2010 revealed that “aqueous extracts and polysaccharides from the roots of A. officinalis are effective stimulators of the physiology of epithelial cells, which can prove the traditional use of marshmallow preparations for the treatment of irritated mucous membranes within tissue regeneration.” Modern science continues to corroborate the wisdom of past generations concerning human health.
Part of the protective advantage of vegetables may be due to the high amount of fiber present in them that confers the benefit to the digestive system. As with arabinogalactan, these plant fibers can be fermented by the microbes present in the intestinal tract to produce short-chain fatty acids and other metabolites. Recently, attention has been given to the impact of diet on the intestinal barrier, the regulation of host immunity, and inflammatory response. The mucilaginous compounds present in demulcent herbs help to soothe the gastric mucosa in cases of mild irritation. Whereas, L-Glutamine may be beneficial for supporting the optimal permeability of the intestinal tract in situations that require a more specific approach.* Overall, it seems reasonable to conclude that a strategy supporting gut health with a combination of lifestyle modifications, targeted herbs, and amino acids may produce the most benefit.Click here to watch our on-demand webinar “Sustamine & Gut Health “The Unique Dipeptide, L-Alanyl-L-Glutamine” with Danielle Citrolo, Pharm.D”
*This statement has not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.
 The Power of Prevention–Chronic Disease…the Public Health Challenge of the 21st Century. 2009 National Center for Chronic Disease Prevention and Health Promotion at the CDC. Accessed online at https://www.cdc.gov/chronicdisease/pdf/2009-Power-of-Prevention.pdf
 Buela KG, Omenetti S, Pizarro TT. Cross-talk between type 3 innate lymphoid cells and the gut microbiota in inflammatory bowel disease. Curr Opin Gastroenterol. 2015 Sep 21.[Epub ahead of print] PubMed PMID: 26398682.
 Kapit, W., Macey, R., Meisami, E. The Physiology Coloring Book, HarperCollins College Publishers, 1987, Pg. 74.
 Ibid. The Physiology Coloring Book
 Goldberg R, Prescott N, Lord GM, MacDonald TT, Powell N. The unusual suspects–innate lymphoid cells as novel therapeutic targets in IBD. Nat Rev Gastroenterol Hepatol. 2015 May;12(5):271-83.
 Ibid. Curr Opin Gastroenterol. 2015
 Ibid. Curr Opin Gastroenterol. 2015
 Geremia A, Biancheri P, Allan P, Corazza GR, Di Sabatino A. Innate and adaptive immunity in inflammatory bowel disease. Autoimmun Rev. 2014 Jan;13(1):3-10.
 Andrade ME, et al. The role of immunomodulators on intestinal barrier homeostasis in experimental models. Clin Nutr. 2015 Jan 23. pii: S0261-5614(15)00034-5. http://www.ncbi.nlm.nih.gov/pubmed/2566031
 Ibid. Clin Nutr. 2015
 Lambert GP, Broussard LJ, Mason BL, Mauermann WJ, Gisolfi CV. Gastrointestinal permeability during exercise: Effects of aspirin and energy-containing beverages. J Appl Physiol.2001;90(1985):2075–2080.
 Zuhl M, et al. The effects of acute oral glutamine supplementation on exercise-induced gastrointestinal permeability and heat shock protein expression in peripheral blood mononuclear cells. Cell Stress & Chaperones. 2015;20(1):85-93. doi:10.1007/s12192-014-0528-1.
 Ibid. Cell Stress & Chaperones. 2015
 Hoffman et al. L-alanyl-L-glutamine ingestion maintains performance during a competitive basketball game. Journal of the International Society of Sports Nutrition 2012, 9:4Med. 2010 Oct;16(10):1065-71.
 Ibid. Journal of International Society of Sports Nutrition. 2012
 Deters A, et al. Aqueous extracts and polysaccharides from Marshmallow roots (Althea officinalis L.): cellular internalisation and stimulation of cell physiology of human epithelial cells in vitro. J Ethnopharmacol. 2010 Jan 8;127(1):62-9.