Fact Checked
Evidence Based Research
This article was written by one of our team of experienced writers, and fact-checked by our experts or our editors. The numbers in parentheses (e.g., 1, 2, 3, etc.) throughout the article are reference links to peer-reviewed studies.
Our team of experts includes a board-certified physician, nutritionists, dietitians, certified personal trainers, strength training experts, and exercise specialists. We are committed to providing our readers with evidence-based information that is grounded in the latest scientific research.

12 Best Glutamine Supplements Reviewed for 2023

Glutamine is a supplement worth taking for its many potential health and performance-aiding benefits.
Ash, ACE, MSc
We provide honest reviews based on a thorough, multi-point testing methodology . We do earn a commission if you purchase through our links, supporting our independent product assessments. View our disclosure for more details.

We’ve never been ones to just recommend any products, as many are simply ineffective, especially for what they claim to do. But glutamine supplements can absolutely be a useful addition to any nutritional regime, especially for active individuals and even ill individuals. 

Glutamine is a non-essential amino acid that has effects on the immune system, intestines, protein synthesis, and more. And although our bodies produce it naturally, there may be a great benefit in taking an additional dose for a boost.

So today, we’ve reviewed 12 quality glutamine products in addition to a breakdown of this potential health and performance-aiding ingredient…

Editor’s Pick: Optimum Nutrition Glutamine Powder 5000mg

Optimum Nutrition Glutamine Powder
Optimum Nutrition Glutamine Powder

Optimum Nutrition products are among the most popular and for good reason. Their products are top-notch. 

Key features:

  • 5g L-glutamine per serving
  • Powder

Makers: Optimum Nutrition 

Main ingredients: L-glutamine

Other ingredients: None

Pros

  • Optimal dose
  • Quality product from top company
  • GMP certified

Cons

  • A little pricey
  • Few complaints of unpleasant side effects
Best Price

Optimum Nutrition Glutamine Powder

Optimum Nutrition Glutamine Powder

Optimum Nutrition Glutamine Powder

Optimum Nutrition Glutamine Powder comes in four sizes, may support muscle recovery, unflavored, made with Pure L-Glutamine.

NOW L-glutamine capsules 500mg

Now Supplements L Glutamine
Now Supplements L Glutamine

Now Supplements is a must-have in any product list. They provide high-quality products at an attractive price point.

Key features:

  • 500mg L-glutamine (free-form) per serving
  • Veggie caps

Makers: NOW Supplements

Main ingredients: L-glutamine

Other ingredients: Rice flour, cellulose, and magnesium stearate

Pros

  • Cheap
  • Convenient veggie caps
  • GMP certified
  • Lab-tested
  • Vegetarian/vegan

Cons

  • Few complaints of ineffectiveness
Best Price

NOW Supplements, L-Glutamine 500 mg

NOW Supplements, L-Glutamine 500 mg

NOW Supplements, L-Glutamine 500 mg

NOW Supplements, L-Glutamine 500 mg supports immune function, nitrogen transporter, no harmful pesticides, sulfites, steroids or allergens.

Optimum Nutrition Glutamine Caps 1000mg

Optimum Nutrition L Glutamine Capsules
Optimum Nutrition L Glutamine Capsules

This is a capsule version which many people find to be more convenient than powder options. You’ll get 1g per serving (two capsules) and it’s a great option for getting your additional daily glutamine intake. 

Key features:

  • 1g L-glutamine per serving (2 capsules)

Makers: Optimum Nutrition

Main ingredients: L-glutamine

Other ingredients: Gelatin, magnesium stearate

Pros

  • Affordable
  • Convenient capsules
  • GMP certified

Cons

  • Few complaints of unpleasant side effects
Best Price

Optimum Nutrition L-Glutamine Capsules 1000mg

Optimum Nutrition L-Glutamine Capsules 1000mg

Optimum Nutrition L-Glutamine Capsules 1000mg

Optimum Nutrition L-Glutamine Capsules 1000mg may support muscle recovery. You can use as pre-workout and before bed.

BulkSupplements Glutamine Powder

Bulksupplements L Glutamine Powder
Bulksupplements L Glutamine Powder

BulkSupplements products are very basic but also lab-tested for purity and potency. Not to mention, it’s a brand that many users are drawn to because of the value. 

Key features:

  • 1000mg L-glutamine
  • Powder

Makers: BulkSupplements

Main ingredients: L-glutamine

Other ingredients: None

Pros

  • Great overall value
  • Lab-tested and verified
  • Non-GMO
  • Very popular product

Cons

  • Complaints of ammonia smell in some bags
Best Price

BulkSupplements L-Glutamine Powder

BulkSupplements L-Glutamine Powder

BulkSupplements L-Glutamine Powder

BulkSupplements L-Glutamine Powder is lab-tested for purity & quality, do muscle recovery, supports immune function, has no fillers or additives.

Pure Encapsulations L-Glutamine Powder

Pure Encapsulations L Glutamine Powder
Pure Encapsulations L Glutamine Powder

Pure Encapsulations L-glutamine powder is pure for sure as it has no other ingredients except for what you pay for. 

Key features:

  • 3g L-glutamine per serving (free-form)

Makers: Pure Encapsulations

Main ingredients: L-glutamine (free-form)

Other ingredients: None

Pros

  • Pure and simple
  • Hypoallergenic
  • Vegan

Cons

  • Pricey
  • Few quality concerns
Best Price

Pure Encapsulations L-Glutamine Powder

Pure Encapsulations L-Glutamine Powder

Pure Encapsulations L-Glutamine Powder

Pure Encapsulations L-Glutamine Powder is hypoallergenic, has pure ingredients, supports lean muscle, gastrointestinal health.

OWN PWR Glutamine Powder

Own Pwr L Glutamine Powder
Own Pwr L Glutamine Powder

OWN PWR may not be as popular as the others on our list but it’s a solid glutamine product that’ll work just as good. 

Key features:

  • 5g L-glutamine per serving

Makers: OWN PWR

Main ingredients: L-glutamine

Other ingredients: None

Pros

  • Solid option for a decent price
  • GMP certified

Cons

  • Few quality concerns/unhappy users
Best Price

OWN PWR L-Glutamine Powder

OWN PWR L-Glutamine Powder

OWN PWR L-Glutamine Powder

OWN PWR L-Glutamine Powder can be used before, during, after training, as well between meals, and on a non-training day. It's unflavored powder.

Kaged Muscle Fermented Glutamine Powder 500g

Kaged Muscle L Glutamine Powder 500 Gram
Kaged Muscle L Glutamine Powder 500 Gram

Kaged Muscle glutamine delivers not only due to the ingredients but it’s also Informed-Sport and Choice certified (tested for banned substances) plus it has a Micropure guarantee (purity and potency) so you know you’re getting exactly what you expect and nothing less.

Key features:

  • 5g L-glutamine (fermented) per serving

Makers: Kaged Muscle

Main ingredients: L-glutamine (fermented)

Other ingredients: None

Pros

  • Fermented l-glutamine
  • Informed-Sport and Choice certified
  • Micropure guarantee (purity and potency)
  • Vegan
  • No fillers

Cons

  • Few unsatisfied users
Best Price

Kaged Muscle Fermented Glutamine Powder 500g

Kaged Muscle Fermented Glutamine Powder 500g

Kaged Muscle Fermented Glutamine Powder 500g

Kaged Muscle Glutamine Powder 500g is gluten-free, fermented, non-GMO, certified banned substances, no fillers, third party tested. Build muscle, combat metabolism, Speed recovery.

MuscleTech Essential Series Platinum 100% Glutamine Powder

Muscletech Glutamine Powder
Muscletech Glutamine Powder

MuscleTech products have been around for quite some time and they’ve definitely earned their reputation as one being on the best. This product is HPLC tested and ultra-pure so you know what you’re getting and that’s quality.

Key features:

  • 5g glutamine (micronized) per serving

Makers: MuscleTech

Main ingredients: L-glutamine

Other ingredients: None

Pros

  • HPLC tested
  • Micro creatine for better absorption
  • Decent value
  • GMP certified

Cons

  • Complaints of no results
  • Reviews of container being too small
Best Price

MuscleTech Platinum 100% Glutamine Powder

MuscleTech Platinum 100% Glutamine Powder

MuscleTech Platinum 100% Glutamine Powder

MuscleTech Platinum 100% Glutamine Powder replenish plasma glutamine, HPLC tested, it's flavorless. Non-stimulant.

Thorne Research L-Glutamine Capsules 500mg

Thorne Research L Glutamine
Thorne Research L Glutamine

Thorne Research is a superior brand that produces well-researched products manufactured in-house for optimal quality.

Key features:

  • 500mg glutamine caps

Makers: Thorne Research

Main ingredients: L-glutamine

Other ingredients: Hypromellose (derived from cellulose) capsule, Silicon Dioxide

Pros

  • Lab-tested
  • Clean manufacturing practices

Cons

  • Some complaints of upset stomach
Best Price

Thorne Research – L-Glutamine Caps

Thorne Research – L-Glutamine Caps

Thorne Research – L-Glutamine Caps

Thorne Research - L-Glutamine Caps promote GI and immune health. Free of soy, dairy, gluten, and artificial flavors.

Jarrow Formulations L-Glutamine Tablets 1000mg

Jarrow Formulations L Glutamine
Jarrow Formulations L Glutamine

Jarrow is a well-known name in the world of nutritional supplements founded in 1977 and they continue to deliver on the quality that has made them a household name. 

Key features:

  • 1000mg L-glutamine per serving
  • Easy-solv tablets

Makers: Jarrow Formulations

Main ingredients: L-glutamine

Other ingredients: Cellulose, stearic acid (vegetable source), silicon dioxide, magnesium stearate (vegetable source) and a food-grade coating

Pros

  • Affordable
  • USP grade
  • GMP certified

Cons

  • Complaints about large tablets
  • Some users had unpleasant side effects
Best Price

Jarrow Formulations L-glutamine Tablets

Jarrow Formulations L-glutamine Tablets

Jarrow Formulations L-glutamine Tablets

Jarrow Formulations L-glutamine Tablets supports muscle tissue, immune function, and intestinal health. cGMP certified.

NutraBio L-Glutamine Powder 500mg

Nutrabio L-Glutamine Powder
Nutrabio L-Glutamine Powder

NutraBio L-glutamine is a vegan fermented product and it’s HPLC tested for potency. It’s a viable, quality option for glutamine supplementation. 

Key features:

  • 5g L-glutamine (Kyowa Quality) (fermented)

Makers: NutraBio

Main ingredients: L-glutamine

Other ingredients: Absolutely none

Pros

  • HPLC tested 
  • GMP certified 
  • Lab-tested
  • Vegan

Cons

  • Few complaints if powder quality.
Best Price

NutraBio L-Glutamine Powder 500mg

NutraBio L-Glutamine Powder 500mg

NutraBio L-Glutamine Powder 500mg

NutraBio L-Glutamine Powder 500 mg is HPLC lab-tested, has no fillers, no excipients, n0n-GMO, free of gluten, BSE/TSE free.

Nutricost Glutamine Powder 5000mg

Nutricost L Glutamine Powder
Nutricost L Glutamine Powder

Lastly, Nutricost glutamine is a superior quality supplements, with only clean ingredients that work. It’s tested and GMP compliant so that you can have peace of mind when buying.

Key features:

  • 5g L-glutamine

Makers: Nutricost

Main ingredients: L-glutamine

Other ingredients: None

Pros

  • Fairly priced
  • GMP compliant
  • Third-party tested
  • Non-GMO

Cons

  • Few unsatisfied users/complaints of bad taste
Best Price

Nutricost L-Glutamine Powder

Nutricost L-Glutamine Powder

Nutricost L-Glutamine Powder

Nutricost L-Glutamine Powder is non-GMO, gluten-free, the third party tested.

How We Ranked

The product selections on our list were based on certain criteria to ensure we recommend only the best quality options currently available on the market. 

Here are the main factors we took into consideration…

Ingredients – Each product should contain a therapeutic amount of the active ingredient and very limited additional ingredients if any at all.

Effectiveness â€“ This will depend entirely on the quality of the ingredients in the product but we only picked quality options from reputable companies.

Manufacturing Standards â€“ Ideally, products are produced and stored in a cGMP facility which ensures quality.

Side Effects â€“ Side effects are sometimes inevitable when it comes to supplementation which doesn’t always mean there’s something wrong with the product as one person may experience a side effect and someone else may not. 

However, products should only contain ingredients that are generally considered safe for most people with little chance of causing discomfort or other undesirable effects. User feedback is also sometimes a good way to determine the overall quality of a product.

Who Should Buy Glutamine?

Healthy individuals who have a realistic expectation when it comes to supplementation. You may or may not ‘feel’ a difference with how glutamine acts in the body but that’s the case with most supplements. You take them in recommended doses consistently as part of a health regime and trust in the research that is available on the potential benefits.

How Do I Pick A Good Glutamine Product For Me? 

Budget is an important criterion as there’s no need to spend a lot of money on supplements. There are great products from reputable companies that won’t break the bank and you can make a decision based on the information provided to you. But, always do your own due diligence. 

Many of the products have 5g glutamine per serving but not everyone needs this much and you may prefer a certain brand over the other based on your own reasons. But we chose some of the best we could find so quality shouldn’t be an issue either way.

Benefits of Glutamine

L-glutamine is naturally produced in the body so it’s a non-essential amino acid and the most abundant in the body. It makes protein plus plays a role in other functions in the body. But there’s a difference between L-glutamine (the kind we’re reviewing) and D-glutamine; which is apparently not that important in living organisms plus it has a slightly different molecular structure than L-glutamine. (1)

It’s also important to note that glutamine is found in some foods as well such as beef, corn, white rice, eggs, skim milk and more. But foods that contain protein typically contain some glutamine.

Now let’s talk about some of the benefits.

Essential for critically/metabolic stress

L-glutamine, on the other hand, can be effectively used by the body exogenously and sometimes it’s even necessary. Research shows that glutamine becomes an essential amino acid in critically ill individuals. In fact, one scientific review explained that when the body is under extreme stress, the requirement for glutamine intake exceeds the body’s own ability to produce it in necessary amounts. (2, 3)

This includes major surgery and sepsis

Immune health

Glutamine plays a role in the health of the immune system because it acts as the fuel for cells. And as we previously discussed, metabolic stress factors can deplete the glutamine in our bodies. (4, 5)

And when glutamine is depleted, we become more susceptible to a weakening and reduced functioning of the immune system. But the body can tap into protein which contains glutamine although this isn’t ideal as it’d result in muscle loss. (6, 7)

Another potential benefit of glutamine is that it may even be effective for animals with compromised immune systems due to illness. (8)

But one thing to note is that glutamine may not benefit healthy individuals where immune system function is concerned. 

Now let’s talk about glutamine’s importance for the intestines.

The intestines are the largest immune organ in the body due to its many cells that affect immune function. (9)

Well, glutamine plays a big role in maintaining the health of your body by helping to keep toxins from moving into systematic circulation from the gut lumen. It helps to keep the intestinal barrier intact, preventing it from deterioration. (10)

The barrier is essential for healthy nutrient absorption plus cell production and function (11, 12)

Muscle growth, recovery, and performance

Glutamine is an amino acid that functions as a building block of protein. However, it’s effects on muscle growth are not promising and likely very subtle at the least if there is any effect, for healthy individuals. But it does seem to have some effect on exercise recovery and soreness. (13)

One study found that glutamine has no significant effect on muscle performance, body composition, or even muscle protein degradation, although this was determined from several young and healthy adults. (14)

Another study found that glutamine and carb supplementation reduces blood ammonia in endurance athletes during long, strenuous activity. Well, increased blood ammonia typically causes fatigue so this is great information for endurance athletes to be able to perform for extended periods. (15)

Does Glutamine Have Side Effects?

High doses of glutamine can potentially have side effects such as nausea, vomiting, dizziness, headache, fatigue, rash, and the typical side effects that come with supplementing with more than the recommended doses. Although, some people may just not react well to a certain ingredient and in that case, it’s best to stop right away. 

The typical diet contains anywhere from 3-6 grams of glutamine per day, which of course varies. 

But up to 14+ grams per day has shown to pose minimal to no health concerns, therefore, convincing us that recommended supplementation (up to 10 grams per day) in addition to dietary intake should be OK for most people.

Although, we don’t recommend taking any more than what the label says to take since there needs to be more long-term studies of higher doses. (16, 17)

One study concluded that enhanced glutamine intake (40g/d in one study) may have substantial side effects. (18)

Frequently Asked Questions

What is glutamine?

It’s a non-essential amino acid naturally produced in the body and found in some foods and it functions to help the body build proteins.

But glutamine also has benefits for immune and intestinal health in addition to potentially positive effects on recovery and performance.

L-glutamine is an important amino while D-glutamine apparently lacks in importance.

What is glutamine used for?

It’s mainly used to help with recovery in addition to immune and gut health which it is in fact, most effective for.

How much glutamine should I take to see benefits?

For healthy individuals, 5-10 grams per day is a safe and effective dose. Although, doses up to 14g have been proven safe and effective.

Does glutamine have side effects?

Research has shown that enhanced glutamine supplementation (up to 40g/d in one study) may result in substantial side effects.

It’s important to read the product label and not exceed the recommended dosages.

Wrapping Up

You can’t go wrong with any of the above glutamine supplements that made our list. All are solid options and are useful as an inclusion in your supplement regime. Again, we definitely don’t recommend all products just because they claim to do something but there are some worth your time like glutamine.


If you have any questions or need further clarification about this review, please leave a comment below, and Ash will get back to you as soon as possible.

Stay on top of the latest fitness news and updates by adding Fitness Volt to your Google News feed: Follow us on Google News You can also follow us on Twitter, Facebook, Instagram, and YouTube for even more content.
Ash, ACE, MSc
Ash, ACE, MSc
Ash is a highly respected fitness expert and certified personal trainer through the American Council on Exercise (ACE). With a B.A. in biology from Rutgers and an M.S. in Exercise Science (Kinesiology) from CBU, she brings a wealth of knowledge and expertise to her work. Ash is dedicated to helping people achieve their fitness and health goals through personalized training and nutrition plans. With a passion for fitness and a deep understanding of the science behind healthy living, she is able to create effective and sustainable programs that deliver real results. Whether you're looking to lose weight, build muscle, or just feel better in your own skin, Ash is the expert you can trust to guide you on your journey to a healthier and happier life.
Subscribe
Notify of
guest

0 Comments
Inline Feedbacks
View all comments

Related