About DigestShield®

How Does DigestShield® Work?

Digital man with shield repelling bacteria

DigestShield® works by breaking down gluten, dairy, fats, carbohydrates, and protein into small pieces for your body to use, shielding against possible effects such as inflammation and discomfort.

It contains 5 prebiotics, 11 probiotics, and 20 enzymes, all in one capsule. It also helps to restore proper microflora balance by providing a full complement of beneficial probiotic bacteria. (15)

DigestShield® was created at East Tennessee State University by two PhDs and was clinically tested in 2019. It is endorsed nationally by Tom Rogers, MD, founder of Performance Medicine.

Just think of taking DigestShield® as a way to provide your body with everything it needs to protect itself from potential “bad actors” commonly found in our modern diet.

Digestive Powerhouse

DigestShield® makes digestion of everything you eat better, giving you the most nutrition from a meal while protecting against bad actors in your diet.

DigestShield® contains a revolutionary blend of enzymes, probiotics and prebiotics to assist with the efficient digestion of gluten, dairy, beans (legumes), fats, carbohydrates and proteins.

Here is a typical meal and how DigestShield® works. (References listed below back up the explanations.)

  • Gluten: Protease Enzymes and serrapeptase work to break down the gluten and gliadin found in the bread, beer, and processed deli slices. (2, 7)
  • Lectins: Vegetarian chitosan protects you from the wheat lectins in the bread.(12-13)
  • Lactose: Lactase can break down the lactose found in cheese and other dairy products. (4)
  • Phytates: Phytase can break the phytates found in bread and other grains into a form of phosphorus that the body can use. (6)
  • Cellulose: Cellulase, hemicellulase, and xylanase all break down the indigestible cellulose found in the cell walls of plants like tomatoes, lettuce, and onions. (5)
  • Fats, Carbohydrates, and Proteins: Lipase enzymes break down the fats found in meat, cheese, and condiments. Amylase breaks down the carbohydrates in beer, vegetables, and bread. Protease breaks down the protein in meat, cheese, and bread. (8)
Sandwich and Beer


The enzymes in our formula break down gluten, dairy, casein, carbohydrates, protein, and fat. Enzymes are biocatalysts that break the bonds of the food we eat into small enough forms for our body to use. There are many different enzymes found in the human body and they all have specific jobs. Our formulation includes a carefully chosen combination of plant-based enzymes to help you get the most from the foods you eat.

Plant-based enzymes, found in the majority of enzyme supplements, originate from plant organisms that produce acid-stable enzymes. These enzymes are purified and characterized which means their pH is well-known and easily determined. Most of these enzymes can work in a pH range of 2 to 9 without loss of activity.1  This means our blend of enzymes will survive the harsh acidic environment of your stomach. Here is the line-up of enzymes in DigestShield® and what they do:

Protease Enzymes

Protease class enzymes have been shown to have the hydrolytic capacity for breaking down gluten. This means that enzymes in DigestShield® can break the toxic protein, gliadin into harmless constituents before an immune response is triggered.


Lactose is a disaccharide found in milk and other dairy products. Each lactose molecule is composed of a galactose molecule and a glucose molecule bound together. The enzyme, lactase, is required to cleave the bond between these two so that the body can use the individual glucose and galactose molecules. However, many people stop producing this enzyme after the age of two. This enzyme deficiency prevents the breakdown of lactose, which can often lead to gas, bloating, and intestinal pain after consuming milk and other dairy products.4 We have included a dose of lactase in DigestShield™ to break this sugar down for use before it causes any problems.

Cellulase, Hemicellulase, and Xylanase

Cellulose is found in the cell walls of all plants and unfortunately, humans lack the necessary enzymes required to break them down. Usually, since the cellulose will pass through the stomach and small intestine intact, the bacteria in the large intestine will ferment it. This allows us to use some of the energy available from cellulose but it can produce a lot of gas in the process, which can lead to bloating or passing gas. Cellulase, hemicellulase, and xylanase all break down cellulose before they reach the large intestine.


Phytic acid is the storage form of phosphorus found in many seeds, cereals, and plant oils. When consumed, it has been shown to bind to essential minerals such as iron, zinc, and calcium. The resulting mineral compound is too large to be absorbed and can lead to nutrient deficiencies.6 Bacteria found in the gut of ruminant animals like cows produce phytase but we do not.6 We include phytase to cleave the bonds of phytic acid, releasing the phosphorus in a usable form and preventing it from causing mineral deficiencies.


This protease class enzyme helps to break down proteins. It is not naturally found in the human body but as a supplement, serrapeptase has been shown to reduce inflammation.7

Plant-Based Digestive Enzymes

Lipase, protease, and amylase are terms for the general categories of enzymes that break down fats, proteins, and carbohydrates, respectively, into small enough particles for absorption in the gut. We include a full complement of plant-based lipase, protease, and amylase enzymes to help you digest and absorb all of the foods in your diet.8 Prebiotics is the term used to refer to fermentable carbohydrates which stimulate and nourish probiotics and beneficial bacteria strains in the large intestine. They serve as a substrate and food for the good bacterial colonies there.9 DigestShield® contains a proprietary mixture of prebiotics and herbs chosen to support the probiotics included in our formula.

Chitosan Oligosaccharide

Chitosan Oligosaccharide in our formula serves the purpose of both prebiotic, lipid (fat) aggregator, and lectin decoy. Plant lectins are anti-nutrient proteins found in many foods we eat including grains such as wheat. Lectins bind to cells in our digestive tract because of the sugar coating, or glycocalyx that surrounds each cell. Different lectins have been shown to have different attractions to specific sugars.10 Wheat lectin, known as wheat germ agglutinin (WGA), has been demonstrated to have a sugar-binding attraction to N-acetyl-D-glucosamine, meaning it will bind to that sugar whenever possible.11

Chitosan is a natural source of N-acetyl-D-glucosamine. By substantially including it in the DigestShield® formula, we are providing a decoy to which the dangerous lectins in your diet can bind. This means that instead of binding to your gut wall and causing damage, the lectin can bind to your chitosan and be harmlessly carried out of your body during a bowel movement.12-13

Our mushroom-derived chitosan is the first ultra-low molecular weight (3000 Dalton) product of its type in the world. Most sources of N-acetyl-D-glucosamine are derived from shrimp and crab shells. Our chitosan is derived from the cell wall of the oyster mushroom. Additionally, the chitosan in DigestShield® is several orders of magnitude smaller (on a molecular scale, not a dosage scale) than any other on the market. This is referred to as Ultra Low Molecular Weight (ULMW) and provides a much greater binding potential. It addresses harmful wheat lectins, potato lectins, and lectins found in nightshade vegetables, and is capable of binding lipids in the diet to reduce absorption.

Fructooligosaccharides (FOS)

Short-chain FOS serves as a substrate for gut bacteria and is metabolized to short-chain fatty acids. This can lead to lowering the pH in the gut environment and promote calcium absorption.13

Alfalfa Powder

Alfalfa is a rich natural source of prebiotics that can promote the growth of beneficial bacteria.14 Probiotics are live bacteria and yeast that are beneficial to health. Though we do not yet have a complete understanding of the full scope of the mechanism that these organisms exert on human health, researchers have studied many strains and found them to have beneficial effects.15

Lactobacillus acidophilus16-18
  • Reduces the damage and toxic effects of mold and yeast growth and can prevent parasite growth
  • Boosts immune function
  • Reduces duration and severity of diarrhea
Lactobacillus casei19-21Lactobacillus casei19-21
  • Helps to manage chronic cases of constipation
  • Can help to reduce the occurrence of lactose intolerance
  • Boots immune function
  • Assist with diarrhea associated with antibiotic use
  • Can reduce the rate and risk of bacterial infections
Lactobacillus rhamnosus22-23Lactobacillus rhamnosus22-23
  • Boots immune function by decreasing intestinal permeability
  • Fights unhealthy bacteria and yeast
  • Can reduce the incidence of irritable bowel syndrome
Bifidobacterium lactis23-26Bifidobacterium lactis23-26
  • Boosts immune function
  • Treat acute diarrhea
  • Reduce occurrence of dental carries
Lactobacillus plantarum27-29Lactobacillus plantarum27-29
  • Boosts immune function
  • Can ease symptoms of irritable bowel syndrome
Lactobacillus brevis30-32Lactobacillus brevis30-32
  • Boosts immune function
  • Decreases peptic ulcer causing H.pylori colonization
  • Can reduce the chance of developing kidney stones
Lactobacillus salivarius33Lactobacillus salivarius33
  • Boosts immune function
  • Inhibits Candida yeast growth
  • Inhibits growth of pathogenic bacteria
Streptococcus thermophilus34-35Streptococcus thermophilus34-35
  • Boosts immune function
  • Can lower the chance of developing kidney stones
Bifidobacterium bifidum36-38Bifidobacterium bifidum36-38
  • Boosts immune function
  • Alleviates irritable bowel syndrome symptoms
  • Can reduce the duration and severity of the common cold
Lactobacillus coagulans39-41Lactobacillus coagulans39-41
  • Boosts immune function
  • Alleviates irritable bowel syndrome symptoms
  • Some evidence for alleviation of rheumatoid arthritis symptoms
Saccharomyces boulardii 42-43Saccharomyces boulardii 42-43
  • Boosts immune function
  • Can reduce the frequency of diarrhea
  • May reduce the symptoms of irritable bowel disease


“DigestShield” is one of my favorites. Gut issues have been a problem for me most of my life. It helps my digestion, in general, but also especially with foods that contain gluten and dairy. It’s not just for those with gluten intolerance, but also anyone with acid reflux, IBS, constipation or any other related digestive issue.

I’ve used “DigestShield” for a number of years and just wouldn’t be without it. Its almost-immediate effect gives me confidence. It keeps me regular and allows me to be able to eat the foods I want w/out worry. I know others who love it as much as I do. I highly recommend you give “DigestShield” a try.

Patsy S Meridith

Wow! I’ve been experiencing stomach issues for several years, which finally led to an abrupt gluten intolerance earlier this year. Eating the right foods to not give me bloating and pain was always a guessing game, until I tried DigestShield. Over the last 3 weeks, I started taking 1-2 capsules before every meal, and am having ZERO pains or discomfort. For the first time in years! I couldn’t be more pleased! THANK YOU for this product!

Lea Anne Wiles

I wanted to take a little time to show my appreciation for the product Gluten Shield. It has absolutely changed my daughter’s life. Before Gluten Shield she went from 123 lbs. to 98 lbs, Her life was miserable, she couldn’t eat without it hurting her stomach and making her sick. After numerous tests and examinations with nothing helping, Dr. Stephen Fry introduced us to Gluten Shield. He recommended she try it. It was great, she takes it before each meal and it works. She now can eat normally and without fear of stomach pain. Thanks for a great product and helping my daughter live a normal life.

Peggy Hollifield

Amazing product!! I use it regularly to regulate my system and find it helps me stay in good health!

If I experience an ailment I double or triple my regular dosage and find I’m usually better the next day. In fact, this product recently helped me overcome a stomach flu.

I would recommend this product to anyone and often do! I’m grateful to have found something that’s readily available and packed full of powerful ingredients.

D. Hanne

I had lots of digestive issues like bloating, acid reflux after pretty much everything I ate, and nausea. Since taking DigestShield a little over a month I have not had as much bloating after meals, no nausea at all after eating, and the acid reflux is definitely getting better without reflux medicine now!

Laura McConnell

I started eating gluten free, in 2014 when I found out I had Hashimoto’s. I was eating about 95% GF but I didn’t really believe I was sensitive to gluten until the holidays rolled around that first year and I started eating all the goodies. I don’t really have digestive issues like the average person, but the gluten causes painful inflammation in my body. About 2 weeks into January I realized that eating the gluten had made my body feel like it had been hit by a truck. The lymph nodes under my armpits swell and ache and I also get patchy itchy skin, mostly in my scalp.

After I started taking DigestShield (it was called Gluten Shield back then) I found I can eat a little gluten here and there and don’t get the achy side effects and the scalp issues are no longer a problem. Now don’t get me wrong I can’t just eat the all the gluten and take a pill, but if I keep my diet mostly GF and take the DigestShield daily – I can eat an occasional hoagie or slice of cake when I want to and don’t suffer the painful inflammation.

Lori Bowman

I didn’t really have digestive issues per say prior to starting to take DigestShield. I started taking it due to the pre/probiotic blend as I believe everyone should take a quality probiotic for overall gut health since the majority of the immune system is found in the gut. I am also a fan of the fulvic acid which is important for mineral balancing and has complement-fixing activity — helping the immune system function optimally and decreasing inflammation.

Benjamin Ross Curtis

My issue was with gluten or maybe after eating that cheat meal on the weekend! DigestShield took away the bloating, cramping and overfilling sensation! I take it every day sometimes more than once a day depending on what I eat.


Before taking DigestShield I had frequent problems with indigestion & heartburn, especially the first hour or so after meals.

After using Digest Shield regularly on a daily basis I noticed those symptoms gradually began to improve, and now I rarely have any problems with reflux or indigestion at all.

I can highly recommend Digest Shield to anyone that has any GI type problems or symptoms, & look forward to continuing to use it on a daily basis.

Ernie Dickson

Before taking DigestShield, it seemed like I was always bloated and just on the edge of discomfort no matter how closely I watched my nutrition. Dinners with friends were stressful, and I avoided a list of foods every day. Still, it always felt like I had just recently had a reaction to something that didn’t agree with my gut.

As I started taking DigestShield, I was skeptical. It came as a recommendation for my wife from her doctor. Reading about it, I couldn’t help but find myself intrigued. I kept my own digestive discomforts mostly to myself. It was shocking to me how much different and better my gut health felt within the first week of taking DigestShield. Now it feels as if I can eat almost anything, and I don’t suffer inequitably. When we have friends over, I can handle dairy for the first time in decades. If I choose to have an espresso, I don’t have the negative reactions that drove me away from coffee for years. And in general, my weight has stabilized and my pants fit better — unexpected but I’ll take it! When I travel, DigestShield is the most important thing that I remember to pack. My only complaint is that no one developed this supplement earlier!

Jacob Meyer

1. CRC Press,. (2015). Handbook of Food Enzymology. Retrieved 28 October 2015, from https://www.crcpress.com/Handbook-of-Food-Enzymology/Whitaker-Voragen-Wong/9780824706869
2. Ehren J, e. (2015). A food-grade enzyme preparation with modest gluten detoxification properties. – PubMed – NCBI . Ncbi.nlm.nih.gov.
3. Hausch, F., Shan, L., Santiago, N., Gray, G., & Khosla, C. (2002). Intestinal digestive resistance of immunodominant gliadin peptides. American Journal Of Physiology – Gastrointestinal And Liver Physiology, 283(4), G996-G1003
4. Järvelä I, Torniainen S, Kolho KL (2009). “Molecular genetics of human lactase deficiencies”. Annals of Medicine 41 (8): 568–75
5. Worthington-biochem.com,. (2015).Cellulase – Worthington Enzyme Manual
6. Mullaney EJ, Daly CB, Ullah AH (2000). “Advances in phytase research”. Adv Appl Microbiol 47: 157–199
7. Al-Khateeb, T., & Nusair, Y. (2008). Effect of the proteolytic enzyme serrapeptase on swelling, pain and trismus after surgical extraction of mandibular third molars. International Journal Of Oral And Maxillofacial Surgery, 37(3), 264-268. doi:10.1016/j.ijom.2007.11.011
8. Mahan, L. Kathleen., Escott-Stump, Sylvia., Raymond, Janice L.Krause, Marie V. (Eds.) (2012) Krause’s food & the nutrition care process /St. Louis, Mo. : Elsevier/Saunders
9. Shoaf, K., Mulvey, G., Armstrong, G., & Hutkins, R. (2006). Prebiotic Galactooligosaccharides Reduce Adherence of Enteropathogenic Escherichia coli to Tissue Culture Cells.Infection And Immunity, 74(12), 6920-6928. doi:10.1128/iai.01030-06
10. Li, X., Tushima, Y., Morimoto, M., Saimoto, H., Okamoto, Y., Minami, S., & Shigemasa, Y. (2000). Biological activity of chitosan–sugar hybrids: specific interaction with lectin . Polymers For Advanced Technologies, 11(4), 176-179
11. Sharon, Nathan, and H Lis. Lectins. Dordrecht: Springer, 2007. Print.
12. Hamid R. Masood A. Dietary lectins as disease causing toxicants. Pakistan J of Nutr 2009; 8(3): 293-303
13. Heuvel, E., Muys, T., Dokkum, W., & Schaafsma, G. (1999). Oligofructose stimulates calcium absorption in adolescents. The American Journal Of Clinical Nutrition, 69(3), 544-548. Retrieved from http://ajcn.nutrition.org/content/69/3/544.full
14. Caselate de Sousa VM, Freitas dos Santos E, Sgarbieri V. The importance of prebiotics in functional foods and clinical practice. Food and Nutr Sci 2011; 2: 133-144
15. Sanders, M., Guarner, F., Guerrant, R., Holt, P., Quigley, E., & Sartor, R. et al. (2013). An update on the use and investigation of probiotics in health and disease. Gut, 62(5), 787-796. doi:10.1136/gutjnl-2012-30250
16. Beausoleil et al. Effectiveness of yogurt fermented with L. acidophilus Cl1285 & L. casei in antibiotic-induced diarrhea prevention: a randomized/double-blind/placebo-controlled study.Can J Gastroenterol. 2007 Nov;21(11):732-6.
17. Canducci et al. Lactobacillus acidophilus effectiveness against H. pylori. Aliment Pharmacol Ther. 2000 Dec;14(12):1625-9.
18. De Simone et al. Effect of Bifidobacterium bifidum and Lactobacillus acidophilus on gut mucosa and peripheral blood B lymphocytes. Immunopharmacol Immunotoxicol. 1992;14(1-2):331-40
19. Armuzzi A, e. (2001). The effect of oral administration of Lactobacillus GG on antibiotic-associated gastrointestinal side-effects during Helicobacter pylori eradication… – PubMed – NCBI .Ncbi.nlm.nih.gov.
20. Chang E, Yong K, Dong H, Joo C, et al. Lactobacillus casei prevents impaired barrier function in intestinal epithelial cells. APMIS 2011; 119(1): 49-56
21. Almeida CC, Lorena SL, Pavan CR, Akasaka HM, Mesquita MA. Beneficial effects of long-term consumption of a probiotic combination of Lactobacillus casei Shirota and Bifidobacterium breve Yakult may persist after suspension of therapy in lactose-intolerant patients. Nutr Clin Pract 2012; 27(2): 247-51
22. Francavilla, R., Miniello, V., Magista, A., De Canio, A., Bucci, N., & Gagliardi, F. et al. (2010). A Randomized Controlled Trial of Lactobacillus GG in Children With Functional Abdominal Pain.PEDIATRICS, 126(6), e1445-e1452. doi:10.1542/peds.2010-0467
23. Hojsak, I., Snovak, N., Abdović, S., Szajewska, H., Mišak, Z., & Kolaček, S. (2010). Lactobacillus GG in the prevention of gastrointestinal and respiratory tract infections in children who attend day care centers: A randomized, double-blind, placebo-controlled trial. Clinical Nutrition, 29(3), 312-316. doi:10.1016/j.clnu.2009.09.008
24. Arunachalam et al. Enhancement of natural immune function by dietary consumption of Bifidobacterium lactis (HN019). Eur J Clin Nutr. 2000 Mar;54(3):263-7
25. Chouraqui et al. Acidified milk formula supplemented with Bifidobacterium lactis: impact on infant diarrhea in residential care settings. J Pediatr Gastroenterol Nutr. 2004 Mar;38(3):288-92.
26. Söderling, E. (2012). Probiotics and dental caries. Microbial Ecology In Health & Disease, 23(0). doi:10.3402/mehd.v23i0.18582
27. Bixquert Jiménez, M. (2009). Treatment of irritable bowel syndrome with probiotics: An etiopathogenic approach at last?. Revista Española De Enfermedades Digestivas, 101(8), 553-564.
28. Bested, A., Logan, A., & Selhub, E. (2013). Intestinal microbiota, probiotics and mental health: from Metchnikoff to modern advances: Part II – contemporary contextual research. Gut Pathog, 5(1), 3. doi:10.1186/1757-4749-5-3
29. Ducrotté P, Sawant P, Jayanthi V. Clinical trial: Lactobacillus plantarum 299v (DSM 9843) improves symptoms of irritable bowel syndrome. World J Gastroenterol. 2012;18:4012–4018. doi: 10.3748/wjg.v18.i30.4012.
30. Turroni S, et al. (2007) Oxalate consumption by lactobacilli: evaluation of oxalyl-CoA decarboxylase and formyl-CoA transferase activity in Lactobacillus acidophilus. – PubMed – NCBI .Ncbi.nlm.nih.gov.
31. Linsalata M, e. (2004). The influence of Lactobacillus brevis on ornithine decarboxylase activity and polyamine profiles in Helicobacter pylori-infected gastric mucosa. – PubMed – NCBI .Ncbi.nlm.nih.gov. Retrieved 12 October 2015, from http://www.ncbi.nlm.nih.gov/pubmed/15068419
32. Effect of the oral administration of Lactobacillus brevis subsp. coagulans on interferon-alpha producing capacity in humans. (2013). Journal Of The American College Of Nutrition.
33. Shimauchi, H., Mayanagi, G., Nakaya, S., Minamibuchi, M., Ito, Y., Yamaki, K., & Hirata, H. (2008). Improvement of periodontal condition by probiotics with Lactobacillus salivarius WB21: a randomized, double-blind, placebo-controlled study . Journal Of Clinical Periodontology, 35(10), 897-905. doi:10.1111/j.1600-051x.2008.01306.x
34. Perdigon, G., Nader de Macias, M., Alvarez, S., Oliver, G., & Pesce de Ruiz Holgado, A. (1987). Enhancement of Immune Response in Mice Fed with Streptococcus thermophilus and Lactobacillus acidophilus. Journal Of Dairy Science, 70(5), 919-926. doi:10.3168/jds.s0022-0302(87)80095-4
35. Campieri, C., Campieri, M., Bertuzzi, V., Swennen, E., Matteuzzi, D., & Stefoni, S. et al. (2001). Reduction of oxaluria after an oral course of lactic acid bacteria at high concentration. Kidney Int, 60(3), 1097-1105. doi:10.1046/j.1523-1755.2001.0600031097.x
36. de Vrese, M., Winkler, P., Rautenberg, P., Harder, T., Noah, C., & Laue, C. et al. (2005). Effect of Lactobacillus gasseri PA 16/8, Bifidobacterium longum SP 07/3, B. bifidum MF 20/5 on common cold episodes: A double blind, randomized, controlled trial. Clinical Nutrition, 24(4), 481-491. doi:10.1016/j.clnu.2005.02.006
37. De Simone C, Ciardi A, Grassi A, Lambert Gardini S, Tzantzoglou S, Trinchieri V, Moretti S, Jirillo E. Effect of Bifidobacterium bifidum and Lactobacillus acidophilus on gut mucosa and peripheral blood B lymphocytes. Immunopharmacol Immunotoxicol. 1992;14(1-2):331-40.
38. Guglielmetti S, Mora D, Gschwender M, Popp K. Randomised clinical trial: Bifidobacterium bifidium MIMBb75 significantly alleviates irritable bowel syndrome and improves quality of life – a double-blind, placebo-controlled study. Aliment Pharmacol Ther 2011; 33: 1123-1132.
39. Hun, L. (2009). “Bacillus coagulans significantly improved abdominal pain and bloating in patients with IBS”. Postgraduate Medicine 121 (2): 119–124.doi:10.3810/pgm.2009.03.1984
40. Baron, M. (2009). “A patented strain of Bacillus coagulans increased immune response to viral challenge”. Postgraduate Medicine 121 (2): 114–118.doi:10.3810/pgm.2009
41. Mandel DR, e. (2010). Bacillus coagulans: a viable adjunct therapy for relieving symptoms of rheumatoid arthritis according to a randomized, controlled trial. – PubMed – NCBI .Ncbi.nlm.nih.gov. Retrieved 12 October 2015, from http://www.ncbi.nlm.nih.gov/pubmed/20067641
42. Vandenplas Y (July 1999). “Bacteria and yeasts in the treatment of acute and chronic infectious diarrhea. Part II: Yeasts”. Clin. Microbiol. Infect. 5 (7): 389–395. doi:10.1111/j.1469-0691.1999.tb00162.x
43. Choi CH, e. (2011). A randomized, double-blind, placebo-controlled multicenter trial of saccharomyces boulardii in irritable bowel syndrome: effect on quality of life. – PubMed – NCBI. Ncbi.nlm.nih.gov.