Glycine for Gut Barrier Integrity
Glycine protects intestinal tissue in animal models, but no human trial has shown improved barrier function.
Overview
Verdict
How It Works
Dosing & Protocol
Typical dose
- Recommended dose
- Not established; animal studies used 2-5% dietary glycine, with no human trial of gut barrier outcomes
- Expected timeframe
- Not established
Protocol
- form
- Not applicable
- duration
- Not applicable
- co factor
- Evidence is insufficient. Glycine is the most abundant amino acid in collagen and has documented cytoprotective effects on intestinal epithelium in animal models - it reduces injury from ischaemia-reperfusion, NSAIDs and alcohol in rodents, apparently through glycine-gated chloride channels on epithelial and immune cells. All of that is preclinical. No randomised human trial has measured intestinal permeability, tight junction function or any gut barrier outcome after oral glycine, and the doses used in animal work (2-5% of the diet) have no straightforward human equivalent. Glutamine, by contrast, has at least been tested in humans for this endpoint.
- titration
- Not applicable
- starting dose
- Not applicable
Evidence
What the studies say
No studies are yet linked to both Glycine and Gut Barrier Integrity.
Safety
Caveats
Persistent gut symptoms deserve a diagnosis before a supplement: coeliac disease, inflammatory bowel disease, bile acid diarrhoea, pancreatic insufficiency and microscopic colitis are treatable and often missed. Blood in the stool, weight loss, nocturnal symptoms, anaemia or a change in bowel habit after 50 need urgent assessment. Safety: glycine has no established upper intake level; above 3 g it commonly causes nausea and loose stools, which is counterproductive here. It is sedating at 3 g and above, so timing matters. Use caution with clozapine, whose efficacy glycine reduces, and with sedatives and alcohol. No adequate safety data in pregnancy or breastfeeding - avoid in both, and in children without paediatric advice. Bone broth and collagen, common glycine sources marketed for gut health, carry the same absence of trial evidence.
Less likely to help if
Medical Disclaimer
The information provided on this website is for educational and informational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition or before starting any supplement regimen.
Individual results may vary. The statements on this website have not been evaluated by the Food and Drug Administration. Products and information are not intended to diagnose, treat, cure, or prevent any disease.