L-glutamine is the most abundant amino acid in the body and plays a critical role in maintaining the integrity of the intestinal lining. For anyone dealing with leaky gut, IBS symptoms, or general digestive discomfort, supplementing with L-glutamine can help repair and strengthen the gut barrier. Here are the best L-glutamine supplements for gut health available right now.
Quick Comparison
Product
Key Feature
Form
Best For
Rating
Thorne L-Glutamine Powder
NSF Certified for Sport
Powder
Overall gut support
9.5/10
Zinc L-Carnosine Complex
11-in-1 gut formula
Capsules
Comprehensive gut repair
9.3/10
NOW L-Glutamine 500mg
Budget-friendly
Capsules
Best value
9.2/10
Nutricost L-Glutamine Powder
5g per serving, flavored options
Powder
Taste-sensitive users
9.1/10
Pure Encapsulations L-Glutamine 500mg
Hypoallergenic formula
Capsules
Sensitive stomachs
9.0/10
BulkSupplements L-Glutamine Powder
Best bulk value
Powder
Long-term daily use
8.9/10
Essential Stacks Gut L-Glutamine
Made exclusively in USA
Powder
Gut-specific formulation
8.8/10
1. Thorne L-Glutamine Powder – Best Overall
No products found.
Thorne’s L-Glutamine powder is the gold standard for gut health supplementation, backed by NSF Certified for Sport testing and a reputation for pharmaceutical-grade purity.
Each serving delivers 5 grams of free-form L-glutamine that mixes easily into water or smoothies with no aftertaste. The 504-gram tub provides 90 servings and is manufactured in third-party certified facilities. Thorne’s formula is gluten-free, vegan, and GMO-free, making it suitable for virtually any dietary restriction. The NSF certification means every batch is tested for purity, potency, and banned substances.
Pros:
NSF Certified for Sport with rigorous third-party testing
5g clinical dose per serving for effective gut barrier support
Mixes cleanly with no grit, taste, or aftertaste
Cons:
Higher price point than most competitors
Only available in unflavored powder form
Best for: Anyone who wants a premium, clinically dosed L-glutamine with top-tier third-party testing for gut health and intestinal lining repair.
2. Zinc L-Carnosine Complex – Best Comprehensive Gut Formula
Zinc L Carnosine Complex 85mg, 11-in-1 Digestive & Gut Health Support Supplement, with Soothing Herbal Extract Blend, L-Glutamine & Mastic Gum, 100 Capsules, Non-GMO, Vegan
【UNIQUE FORMULA SUPPORT】 Our Zinc L-Carnosine Complex capsules feature an advanced 11-in-1 formula, centered on a zinc-L-carnosine complex and combined with L-glutamine, mastic gum, and a uniquely crafted soothing herbal extract blend, designed to provide comprehensive support for digestive and gut health.
【PREMIUM INGREDIENT BENEFITS】 This thoughtfully developed formula highlights zinc-L-carnosine in a chelated form, helping maintain structural stability and enhance bioavailability. It is further enriched with six soothing herbal extracts, including DGL, slippery elm, berberine, cinnamon, boswellia, and turmeric, to help soothe the digestive tract and support a healthy GI environment.
【SYNERGISTIC SUPPORT】 By bringing together multiple effective ingredients in a synergistic approach, this comprehensive formula goes beyond a single-ingredient solution to support daily digestive health, help maintain microbiome balance, and provide gentle, lasting gut comfort for both men and women.
【100 VEGAN CAPSULES FOR DAILY WELLNESS】 Each bottle contains 100 vegan capsules, providing a 50-day supply, made with easy-to-swallow plant-based capsules and suitable for inclusion in a daily health maintenance routine.
【PREMIUM QUALITY YOU CAN TRUST】 Crafted with premium naturally sourced ingredients, this supplement is non-GMO, produced in a GMP-certified facility, and third-party tested to ensure safety, purity, and potency. It is free from soy, dairy, gluten, and artificial additives, so you can feel confident with every serving.
This 11-in-1 digestive support formula combines L-glutamine with zinc carnosine, slippery elm, marshmallow root, and other gut-healing ingredients for a multi-targeted approach to intestinal repair.
Each serving provides 85mg of zinc L-carnosine alongside L-glutamine, DGL licorice root, aloe vera, and N-acetyl glucosamine. The capsule format includes 60 servings per bottle. This is an ideal option for those who want a synergistic blend rather than standalone L-glutamine, as the additional ingredients address gut lining integrity, inflammation, and mucosal protection simultaneously.
Pros:
Multi-ingredient formula addresses multiple aspects of gut repair
Includes clinically studied zinc carnosine for stomach lining support
Convenient capsule form eliminates mixing
Cons:
Lower L-glutamine dose compared to standalone powders
More expensive per serving than pure L-glutamine
Best for: People who want an all-in-one gut repair supplement combining L-glutamine with complementary gut-healing ingredients.
3. NOW L-Glutamine 500mg – Best Value
No products found.
NOW Foods delivers a reliable, budget-friendly L-glutamine capsule that makes daily gut support accessible without compromise on quality.
Each capsule provides 500mg of free-form L-glutamine in a vegetarian capsule. The 120-count bottle allows flexible dosing — most users take 2-3 capsules daily for a 1,000-1,500mg dose. NOW Foods is SSCI-certified with rigorous in-house testing for label accuracy. The formula is halal, kosher, non-GMO, dairy-free, gluten-free, egg-free, nut-free, soy-free, and vegan. For anyone who wants a simple, no-frills option for daily gut support, this hits the mark at a fraction of the cost of premium brands.
Pros:
Outstanding value at just pennies per serving
Clean formula free from all major allergens
Flexible dosing with 500mg capsules
Cons:
Capsules are relatively large for some users
Lower per-serving dose requires taking multiple capsules
Best for: Budget-conscious buyers who want a pure, well-tested L-glutamine capsule for everyday gut maintenance.
4. Nutricost L-Glutamine Powder – Best Flavored Option
Nutricost L-Glutamine Powder (500 Grams) Unflavored – Gluten Free & Non-GMO, 100 Servings
5000mg of L-Glutamine Powder Per Serving (100 Servings)
1.1 Pounds (500G) of L-Glutamine Powder Per Bottle
Vegetarian Friendly L-Glutamine Powder
Non-GMO, Gluten Free, Soy Free
Manufactured In a NSF Certified, GMP Compliant, FDA Registered Facility
Nutricost offers one of the best-tasting L-glutamine powders on the market with multiple flavor options, making daily supplementation easy and enjoyable.
Available in unflavored, fruit punch, and other flavors, each serving delivers 5g of L-glutamine. The 500g tub provides 100 servings at an exceptional price per serving of around $0.16. The powder is gluten-free, non-GMO, and third-party tested for quality and purity. ConsumerLab has verified Nutricost’s L-glutamine products as containing their listed amounts within acceptable margins. For those who find unflavored powders difficult to take daily, Nutricost’s flavored options make consistency much easier to maintain.
Pros:
Multiple flavor options for better daily compliance
Excellent value at approximately $0.16 per serving
Third-party tested and ConsumerLab verified
Cons:
Flavored versions contain added sweeteners
No NSF or USP certification
Best for: People who struggle with unflavored powders and want an affordable, great-tasting L-glutamine for daily gut support.
5. Pure Encapsulations L-Glutamine 500mg – Best for Sensitive Stomachs
Jarrow Formulas Methyl Vitamin B12 5000 mcg – 60 Chewable Tablets, Naturally Fruit Flavored- Bioactive B12 Vitamin – Supports Cellular Energy Production, Brain Health & Metabolism – 60 Servings
Bioactive B12: Jarrow Formulas Methyl B-12 (methylcobalamin) is the biologically active form of vitamin B12; supports brain and nerve health, cellular energy production, healthy cell replication, and red blood cell production (1)
Homocysteine Metabolism: Methyl B-12 is required for the normal metabolism of homocysteine, supporting its conversion to methionine
Better Retained With Jarrow B12: Research suggests that methyl B-12 is better retained in the body than cyanocobalamin, and supplementation may be needed by some vegetarians and vegans (1)
Convenient Chewable Tablet: Each naturally fruit flavored chewable tablet delivers 5000 micrograms (mcg) of methyl B-12; our B12 methylcobalamin formula does not contain wheat, gluten, soybeans, dairy, egg, fish, shellfish, or peanuts, tree nuts or sesame
Superior Nutrition & Formulation: The goal of Jarrow Formulas is to promote optimal health with high-quality, effective, affordable, and superior formulation of dietary vitamins and supplements; our customers can be assured of purity, value & potency
Pure Encapsulations is the go-to brand for those with food sensitivities, offering a hypoallergenic L-glutamine capsule free from virtually every common allergen.
Each capsule contains 500mg of free-form L-glutamine, with up to 3 capsules recommended daily. Pure Encapsulations is well known among integrative healthcare practitioners for its commitment to clean formulations — every product is free from wheat, gluten, eggs, tree nuts, peanuts, GMOs, hydrogenated fats, artificial colors, flavors, and sweeteners. The brand manufactures in NSF-registered, GMP-compliant facilities. If you work with a functional medicine practitioner for gut issues, this is likely the brand they recommend.
Pros:
Hypoallergenic formula ideal for those with multiple sensitivities
Trusted by integrative and functional medicine practitioners
Manufactured in NSF-registered GMP facilities
Cons:
Premium price point compared to mass-market options
Requires 3 capsules daily for a 1,500mg dose
Best for: Individuals with food sensitivities, autoimmune conditions, or those working with a healthcare practitioner on gut healing protocols.
6. BulkSupplements L-Glutamine Powder – Best for Long-Term Use
No products found.
BulkSupplements delivers pure L-glutamine powder in bulk quantities at industry-low pricing, perfect for anyone committed to long-term daily supplementation.
Available in sizes up to 1kg (2.2 lbs), each 5g serving provides pure L-glutamine with no additives, fillers, or excipients. The powder is unflavored, gluten-free, and undergoes third-party testing for purity, potency, and safety. At roughly $0.10 per serving for the larger sizes, this is one of the most cost-effective ways to supplement with L-glutamine. The minimal ingredient list — just L-glutamine — appeals to those who want nothing extra in their supplement. For anyone following a leaky gut repair protocol that calls for months of consistent supplementation, BulkSupplements keeps costs manageable.
Pros:
Unbeatable price per serving in bulk sizes
Pure single-ingredient formula with no fillers
Third-party tested for purity and potency
Cons:
Large bag packaging is less convenient than tubs
Unflavored only — no taste or mixing enhancements
Best for: Long-term users who want maximum value and pure L-glutamine for extended gut healing protocols.
7. Essential Stacks Gut L-Glutamine – Best Gut-Specific Brand
No products found.
Essential Stacks formulates its L-glutamine specifically for gut health applications, sourcing exclusively from U.S. facilities with a focus on digestive wellness.
Each serving delivers 5g of pure L-glutamine powder designed specifically for gastrointestinal support. The 60-serving tub is unflavored and made exclusively in the USA. Essential Stacks markets this product directly for gut lining repair and intestinal permeability support, making it a targeted option for those dealing with digestive issues rather than athletic recovery. The brand has built a strong following among gut health communities for its focused approach to digestive supplementation.
Pros:
Formulated and marketed specifically for gut health
Made exclusively in U.S. facilities
Strong community reputation among gut health users
Cons:
Fewer servings per container than bulk competitors
Higher per-serving cost than budget options
Best for: Those specifically focused on gut repair and intestinal permeability who want a product designed with digestive health as the primary focus.
8. Revive MD Gut L-Glutamine – Most Potent
No products found.
Revive MD doubles the standard dose with 10g of L-glutamine per serving, offering the highest potency option for serious gut healing protocols.
This physician-formulated supplement delivers 10 grams of L-glutamine per scoop — double what most competitors offer. The 30-serving tub uses a clinical-strength dose that aligns with research supporting higher glutamine intake for intestinal repair. The powder is unflavored, vegan, and designed to mix easily into any beverage. Revive MD is a respected brand in the practitioner supplement space, and their gut-focused formulation reflects an evidence-based approach. If you need to pair L-glutamine supplementation with a probiotic for IBS, the higher dose here provides more therapeutic support.
Pros:
10g per serving — double the standard clinical dose
Physician-formulated for serious gut health applications
Mixes easily with no aftertaste
Cons:
Only 30 servings per tub at the higher dose
Premium pricing reflects the clinical-strength formulation
Best for: Those following practitioner-guided gut healing protocols that require higher L-glutamine doses for intestinal repair and immune support.
9. Life Extension L-Glutamine 500mg – Best for Immune & Gut Dual Support
No products found.
Life Extension brings decades of research-backed formulation to its L-glutamine capsule, supporting both gut integrity and immune function in one supplement.
Each vegetarian capsule delivers 500mg of free-form L-glutamine. The 100-capsule bottle is non-GMO, gluten-free, and manufactured in the USA. Life Extension is known for science-first formulations backed by published research, and their L-glutamine meets the same standards. The brand emphasizes the dual role of L-glutamine in supporting both intestinal lining integrity and immune cell function, making this a solid choice for those seeking comprehensive wellness support beyond just digestive health.
Pros:
Research-backed brand with decades of formulation expertise
Dual support for gut health and immune function
Clean vegetarian formula with no unnecessary additives
Cons:
500mg capsules require multiple pills for higher doses
Mid-range pricing without standout value
Best for: Health-conscious individuals who want a trusted, research-driven L-glutamine supplement for combined gut and immune support.
10. Doctor Danielle Gut Assist – Best Gut-Healing Blend with L-Glutamine
No products found.
Doctor Danielle’s Gut Assist combines L-glutamine with arabinogalactan, licorice root, and other gut-healing botanicals for a targeted leaky gut repair formula.
This powder blend goes beyond standalone L-glutamine by incorporating ingredients that support the mucosal lining, reduce gut inflammation, and promote healthy intestinal permeability. The formula includes L-glutamine as its primary ingredient alongside marshmallow root, slippery elm, and other traditional gut-healing herbs. Each 30-serving container is designed for those on structured gut repair protocols. For additional bloating support, pairing this with a quality probiotic can enhance results.
Pros:
Multi-ingredient blend targets multiple aspects of gut repair
Includes traditional gut-healing herbs alongside L-glutamine
Popular among functional medicine practitioners
Cons:
Herbal taste may not appeal to all users
Higher cost than standalone L-glutamine products
Best for: Those on comprehensive leaky gut or intestinal permeability repair protocols who want L-glutamine combined with complementary healing herbs.
How to Choose the Best L-Glutamine for Gut Health
The most important factor when choosing an L-glutamine supplement for gut health is the dose per serving. Research supporting gut barrier repair typically uses 5-10 grams daily, so look for products that deliver at least 5g per serving in powder form, or be prepared to take multiple capsules if you prefer that format. Capsules typically contain 500-1,000mg each, meaning you may need 5-10 capsules to reach therapeutic levels.
Form matters for both absorption and convenience. Powder formats generally deliver higher doses more efficiently and allow flexible dosing adjustments. Capsules are more convenient for travel and on-the-go use but deliver lower amounts per pill. If you have difficulty with unflavored powders, brands like Nutricost offer flavored options that improve daily compliance.
Third-party testing is critical with amino acid supplements. Look for NSF Certified for Sport, USP Verified, or at minimum, documentation of third-party lab testing. Brands like Thorne, Pure Encapsulations, and NOW Foods maintain strong reputations for quality control. Avoid supplements with unnecessary fillers, artificial colors, or proprietary blends that obscure individual ingredient amounts.
For those with food sensitivities or autoimmune conditions affecting the gut, hypoallergenic brands like Pure Encapsulations offer peace of mind. Check labels for common allergens including gluten, dairy, soy, and eggs — all of which can further irritate a compromised gut lining.
Frequently Asked Questions
What is L-glutamine and how does it help gut health?
L-glutamine is the most abundant amino acid in the body and serves as a primary fuel source for the cells lining the small intestine (enterocytes). It helps maintain the integrity of tight junctions in the gut barrier, supports mucosal repair, and promotes healthy intestinal permeability. When the gut lining is compromised — commonly referred to as leaky gut — L-glutamine supplementation can help repair and strengthen the intestinal barrier.
How much L-glutamine should I take daily for gut health?
Most research supporting gut barrier repair uses doses between 5 and 10 grams per day. Some practitioners recommend up to 15-20 grams daily for acute gut repair protocols, though it’s best to start with 5g and increase gradually. For general gut maintenance, 2-5 grams daily is typically sufficient. L-glutamine is well-tolerated at doses up to 40g per day in healthy adults.
When is the best time to take L-glutamine for gut health?
For optimal gut support, take L-glutamine on an empty stomach — first thing in the morning or between meals. This allows the amino acid to be directly utilized by intestinal cells rather than competing with other amino acids from food for absorption. If you experience any stomach sensitivity, taking it with a small amount of food is acceptable.
How long does it take for L-glutamine to improve gut health?
Most people notice improvements in digestive symptoms within 2-4 weeks of consistent daily supplementation. Gut lining cells turn over approximately every 3-5 days, so the structural benefits of L-glutamine can begin relatively quickly. However, for significant gut repair — especially with conditions like leaky gut or IBS — a 3-6 month supplementation protocol is commonly recommended.
Can I take L-glutamine with probiotics?
Yes, L-glutamine and probiotics complement each other well. L-glutamine repairs and strengthens the gut lining while probiotics help rebalance the gut microbiome. Many functional medicine practitioners recommend taking both as part of a comprehensive gut healing protocol. Take L-glutamine on an empty stomach and probiotics with or without food, depending on the strain.
Are there any side effects of L-glutamine?
L-glutamine is generally well-tolerated with minimal side effects at standard doses. Some people may experience mild bloating, nausea, or headache when first starting supplementation, particularly at higher doses. These effects typically resolve within a few days as the body adjusts. People with liver disease, kidney disease, or Reye’s syndrome should consult a healthcare provider before supplementing with L-glutamine.