While the question is a loaded one, it’s also one of my favorite questions to answer. In fact, it’s the reason I became a doctor in the first place—it opens the door for me to make a real and lasting impact on a patient’s health. There are a variety of approaches for evaluation and management of gut health that can be taken depending on the particular person and their situation. L-glutamine supplements are becoming more popular by the day. They are mostly found in a powder form that you add to a glass of water or smoothie, but L-glutamine can also be ingested by way of supplement capsules. According to a study published in the International Journal of Molecular Science, glutamine is one of the most common amino acids in the blood and cells, and it’s a preferred source of energy for intestinal cells2. The authors also explain that glutamine supplementation can protect the lining of the bowel and help it keep a strong intestinal barrier, in addition to reducing intestinal permeability (i.e., leaky gut), enhancing immune cell function, and supporting the immune system while reducing the inflammatory response3. Another study from 2017 showed that giving a glutamine supplement to athletes4 who compete in the heat could reduce intestinal permeability, which indicates to me that it may be beneficial to consider supplementation before exercising in extreme conditions, in order to support gut health. The amino acid can also be used by patients receiving treatment for head and neck cancer since it may reduce the incidence of painful swallowing and inflammation of the mouth.6 In this setting, the glutamine supplement is providing a protective coating to the mouth and esophagus. L-glutamine has also shown promise for other conditions and bodily functions, such as: One of the leading causes of liver disease, and the need for liver transplantation, in the U.S. is fatty liver and non-alcoholic steatohepatitis (NASH.) People with this condition may also have blood sugar problems, heart disease, metabolic syndrome, and/or obesity. Data from a recent study demonstrated that mice who took a glutamine supplement were protected from developing NASH. 7Prior literature suggests glutamine could help prevent the development of NASH altogether8, but more research is needed to substantiate these findings. Along these lines, a review of the literature on glutamine10 suggests that supplementing with this amino acid reduced the rate of hospital-acquired infections, shortened length of hospital stay, and reduced the rate of in-patient mortality. We should note, however, that many of these studies suggested associations and did not reach statistical significance. Nonetheless, this is still an interesting observation. The same article reviewed other studies and suggested that glutamine supplementation, in general, seems to help regulate the growth of intestinal cells, maintain the gut’s tight junctions11, influence inflammatory cascades, and protect against cell death and stresses. While L-glutamine is an important amino acid when it comes to gut health2, those benefits have greater implications. More than 70% of our immune system lives in the gut. Therefore, autoimmune conditions (Hashimoto’s thyroiditis, fibromyalgia, and many others) could potentially be influenced by glutamine supplementation. Further studies are needed to examine each of these conditions individually, to prove or disprove this hypothesis. Singh is currently the Director of Integrative Gastroenterology at the Susan Samueli Integrative Health Institute at UC Irvine. He is also currently a voluntary Assistant Clinical Professor at UCSD in the Department of Family Medicine and Public Health; prior to this, he has been a Clinical Assistant Professor at UCLA and an Assistant Professor of Medicine at Johns Hopkins University. Singh is a member of the American Academy of Anti-Aging Medicine, American College of Lifestyle Medicine, and many other societies. He is actively involved in the American Gastroenterological Association. He is one of the editors of the textbook of Integrative Gastroenterology, 2nd edition (a Weil Series text) and has written several book chapters and articles. He is dedicated to guiding his clients toward optimal wellness every step of the way, using the most cutting edge technologies to design highly personalized precision based protocols. Towards this end, he founded Precisione Clinic and wrote the book Rescue Your Health to bring the best in preventive medicine to his clients.
