Best Glutamine Supplement

Discover if a supplement of the body’s most abundant amino acid can improve exercise, immunity, gut health, or weight loss.

Medically reviewed by:
Last updated: Nov 15th, 2023
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Best Glutamine Supplement

Amino acids, the building blocks of proteins, play a role in several of the most prominent enzymatic reactions in the body. As such, proper intake of amino acids, or lack thereof, is associated with major health issues in our society, including obesity, insulin resistance and diabetes, gut health, and immunity. If you’re trying to address any of these concerns, supplementing with certain amino acids may help. One particular amino acid — glutamine — seems to play a role in many of these areas.

Glutamine helps your body synthesize proteins and may help you build muscle, recover faster from exercise, boost your immune system, improve your gut health, and speed up weight loss. Scientific research shows that many of these claims have promise, while some still require more research.

Our guide breaks down the features of glutamine supplements and provides our top picks based on cost, quality, and effectiveness. Keep reading to discover if a glutamine supplement is right for your health journey. If you’re in a hurry, check out our top recommendations:

Summary of recommendations

Table of Contents

In this Review

Why you should trust us

At Innerbody Research, we extensively test each health service or product we review, including glutamine supplements. It starts with research, and our team has devoted several hundred hours of research to amino acid supplements and their potential benefits for health, from improving gut linings to bolstering cognition and building muscle. All told, we’ve read more than 100 scholarly articles on the topic, many of which dealt with glutamine, in particular.

After the research phase, we found what we thought were the best glutamine products on the market and tried them for ourselves. A small testing team isn’t a scientific study, but it allows us to give you an honest accounting of these products’ taste, mixability, and apparent efficacy. It also lets us report on these companies’ support systems, their shipping logistics, and the overall customer experience.

Additionally, like all health-related content on this website, this review was thoroughly vetted by one or more members of our Medical Review Board for accuracy. We’ll continue monitoring glutamine supplement developments for new products and science to keep this guide up-to-date.

Over the past two decades, Innerbody Research has helped tens of millions of readers make more informed decisions about staying healthy and living healthier lifestyles.

How we evaluated glutamine supplements

Best glutamine supplements

To evaluate glutamine supplements, we focused on several criteria that get to the heart of what a consumer might need or want from them. We place effectiveness at the top of this list, and it carries the most weight in our considerations for nearly every supplement category we review. Safety is a close second to efficacy; while glutamine as an ingredient typically presents the same degree of safety across brands, there are several other factors that may make one choice safer than another.

Finally, it’s important to look at cost and customer service, the latter of which encompasses things like support infrastructure and shipping logistics. These factors have less of an impact on our final regard for a given company, but they can be what sways your decision one way or the other.

Let’s take a closer look at each for more clarity.


Winner: Revive Glutamine

Glutamine supplements present an interesting situation for evaluating efficacy. In some cases, more glutamine is better. Studies have shown that it’s tolerable in doses of up to 30g/day. There has also been substantial research that illustrates glutamine’s effectiveness at bolstering the intestinal lining against leaky gut syndrome for individuals who need to undergo major surgeries — which typically weaken tight endothelial junctions integral to gut health.

From a gut health and immunity standpoint, Revive easily takes the win for effectiveness, thanks to the fact that its dose is double that of its competitors. It’s not just a matter of the company telling you to take twice as much as those competitors, either; scoops of Revive that are relatively equal in size to those from competitors contain double the amount (10g as opposed to 5g). Revive produces a mixture that’s easier to make and easier to drink despite using a similar quantity of powder.

We consider Transparent Labs a solid runner-up in this category, particularly for those hoping that glutamine will help as a workout supplement. Transparent Labs BCAA Glutamine may only contain the same 5g of glutamine found in so many other brands, but it also proved 8g of branched-chain amino acids (BCAAs), which can improve exercise performance, reduce muscle soreness, and positively impact muscle protein synthesis. This product from Transparent Labs is at the top of our guide to BCAAs for women and is one of our top recommendations for amino acid supplements in general.


Winner: Transparent Labs

When taking any dietary supplement, it’s essential to pay attention to the steps the company takes to ensure its product is safe. Since the Food and Drug Administration (FDA) does not regulate supplements the same way as food and prescription drugs, it’s important to consider a company’s manufacturing, storage, testing, and shipping practices to ensure you’re buying a pure product. Most supplement companies are transparent about these processes and include details on their websites.

Our winner in this category is Transparent Labs. Its glutamine supplement is third-party tested, vegan-friendly, and free of most allergens. The company also makes its third-party testing results available on its website, so you can see how your specific batch performed. One of the other things Transparent Labs does to illustrate its commitment to safety and transparency is list the exact quantities of its “other ingredients.” You’ll usually only see doses for active ingredients in nutritional supplements (and if a company uses proprietary blends, you won’t even get that information). But Transparent Labs lists the doses of each component, right down to the stabilizers it uses to extend a product’s shelf life.


Winner: Kaged

Comparing one glutamine supplement’s pricing to another’s requires a little bit of math. That’s because many of these companies deliver their supplements with varying numbers of servings. Most offer 5g doses, but you could get as few as 30 and as many as 100 servings from a single container, depending on who’s selling it.

We consider Kaged to be the winner for cost because its container offers 100 servings at a better price per gram than anyone else. And that’s before taking its potential subscription savings into account. If you sign up for automatic shipments, you’ll pay around $0.22 for each 5g serving.

Kaged is also one of three companies on our list to offer additional discounts for military personnel, medical workers, teachers, students, and first responders. Once you verify your status, you’ll be able to get 20% off any order up to once per day.

Customer service

Winner: Kaged

Our customer service evaluation takes a handful of things into account, including:

  • Website design
  • Shipping times and tracking
  • Customer support contact options
  • Free programs and advice

Considering all of these, Kaged edged out its competitors. Its shipping speed was matched only by Onnit’s, and while both companies provided order confirmation, shipment confirmation, and out-for-delivery notifications, only Kaged added the final delivery notification to its communications.

Kaged also provides free workout guidance on its website, including 12-week workout programs designed for various goals that take you through proper form and provide motivation to use its supplements to the fullest.

How our top recommendations compare

The sticker price for most glutamine supplements appears pretty similar at first glance, but subtle differences in serving size and serving count can make a big difference in long-term costs. Nd with so many other factors to consider, from money-back guarantees to available flavors, we thought a handy chart would be helpful:

Cost for one order
Number of servings
Serving size
Price per gram of glutamine
Money-back guarantee
90 days
30 days
Free shipping threshold
Sour green apple, tropical punch, strawberry lemonade, blue raspberry

Note: Transparent Labs also includes a generous 8g serving of BCAAs in a 2:1:1 ratio, and it tops our rankings for BCAA supplementation.

What is glutamine?

Glutamine is an amino acid that aids in synthesizing proteins. In addition to building muscle, proteins help keep organs functioning and help the body fight off infection, among other things that keep us alive. The body naturally produces glutamine, which makes it a nonessential amino acid (compared to the nine essential amino acids that the body can only get from dietary sources). But glutamine is also considered to be within a subgroup of nonessential amino acids that the body sometimes needs to consume in order to maintain in sufficient quantities. These are considered conditionally essential amino acids and, in the case of glutamine, may be prescribed for those undergoing chemotherapy or recovering from surgery.

You may notice that there are two forms of glutamine: L-glutamine and D-glutamine. D-glutamine is not essential to body processes, so you’ll often see supplements that include L-glutamine, the form humans need for overall health. L-glutamine is the bioavailable form, meaning that it’s the kind that you can digest and use most easily. Often it is just referred to as glutamine.

There’s also an acetylated form of glutamine called N-acetyl L-glutamine (NAG). This is a more stable form of glutamine that boasts superior solubility in water, but research is conflicting as to whether it's more or less effective than L-glutamine. Some NAG studies show increased absorption, while others see only an increase in the output of urinary metabolites that indicate malabsorption. For now, we prefer L-glutamine, but we would recommend Bulk Supplements as a source of NAG if you’re more interested in that.

In addition to helping with recovery from illness or injury, glutamine may also help with other bodily processes, including:

  • Building muscle
  • Reducing exercise recovery time
  • Supporting immunity
  • Enhancing intestinal health
  • Promoting weight loss

While glutamine’s importance to immunity and intestinal health has been shown through scientific research, more research must be done to affirm its role in muscle building and weight management. Nonetheless, it’s a popular pre- and post-workout supplement ingredient.

Most people can obtain glutamine from a balanced diet, with particularly good sources being foods high in protein. Here are some foods that contain glutamine:

  • Eggs
  • Beef
  • Skim milk
  • Tofu
  • White rice
  • Corn

But if you have certain leaky gut symptoms or you want to try taking your work in the gym to another level, you may benefit from supplementing with glutamine. There is no specific amount of glutamine that you should ingest per day, mainly because it’s an amino acid that your body already naturally produces. However, some clinical studies have noted doses between 5 and 45g per day without severe side effects. Essentially, the amount of glutamine you take daily depends on your desired outcome, the product’s serving suggestions, and your doctor’s recommendations.

Glutamine has nothing to do with gluten, so those who live with celiac disease or maintain a gluten-free diet are in the clear. Just be sure to make sure the supplement you choose is completely gluten-free, as there may be ingredients in addition to glutamine that do contain gluten.

Special Offer: Take 15% of Revive with a Subscription

How glutamine supplements work

Glutamine supplements work by boosting your body’s glutamine levels and helping it synthesize proteins more effectively. This can accelerate muscle and tissue repair and fight illness and infections. Other fitness-related uses for glutamine include muscle building, exercise recovery, and weight loss. While these claims require more clinical research, preliminary studies reveal promising results.

Read on to discover how glutamine supplements can improve your overall health.


Glutamine can help boost the immune system. There is a wealth of research that’s been conducted to show this link, but we’ve highlighted some important studies below:

  • One review found that glutamine is a crucial immunonutrient that can help people recovering from illness or injury recover faster.
  • This review shows that patients recovering from bone marrow transplants who were given glutamine-supplemented diets experienced lower levels of infection than patients who ate a standard diet.
  • This clinical trial found that administering a glutamine-enriched diet to patients after abdominal surgery lowered incidences of infection and shortened hospital stays.
  • Several animal studies show that glutamine boosts the immunity of animals with viral infections.

Intestinal health

Glutamine can help boost intestinal health, particularly by addressing issues stemming from a leaky gut. Since intestinal health is linked to immunity, quieting a leaky gut is another way that glutamine can support immune health.

This review found that glutamine helps protect and repair the gut when it's under stress, while another found that glutamine can help with IBS and intestinal permeability (the clinical term for leaky gut). And a third review found that low glutamine levels are linked to intestinal barrier deterioration.

Muscles and exercise

Glutamine is a popular ingredient in pre- and post-workout supplements. It’s easy to assume that glutamine facilitates muscle building because it helps synthesize protein. However, clinical testing of this hypothesis has not supported it. For example, in one trial, participants took glutamine supplements for six weeks while weight training and showed no significant muscle gain or performance changes. Other similar studies have shown comparable results.

On the other hand, some clinical trials have shown that glutamine supplementation can help reduce muscle soreness after exercise, potentially leading to improved exercise recovery. For example, one trial showed that male participants experienced improved muscle recovery and soreness after supplementing with glutamine and performing knee extensions.

Weight loss

As with muscle building, glutamine’s effect on weight loss is still inconclusive and requires more testing. However, some studies have shown encouraging results. One trial involving obese female patients found that supplementing with glutamine for four weeks led to lower waist circumference and body weight.

Are glutamine supplements a good choice for you?

Glutamine supplements - Kaged, Revive, and Transparent Labs

Photo by Innerbody Research

Glutamine supplements may be a good choice if you’re interested in boosting your immunity or intestinal health. It could also be a good option if you’re recovering from an injury, illness, infection, or other condition that depletes your body’s natural ability to produce glutamine.

For example, glutamine supplementation is often used to help those living with cancer. Glutamine supplementation can lessen one of the severe side effects of chemotherapy called mucositis, which affects the intestines and causes throat and mouth sores. If you’re experiencing these symptoms, talk to your doctor about glutamine supplementation.

Glutamine supplements may also be a good choice if you are interested in building muscle, speeding up exercise recovery, or losing weight. Even though clinical research about glutamine’s impacts is inconclusive, user testimonials of many glutamine-based products indicate that they are effective as pre- and post-workout supplements.

Who should avoid them?

Some health conditions may be exacerbated by glutamine supplementation. It’s important to talk to your doctor before beginning any new supplement, as qualified healthcare practitioners have the best knowledge of any potential contraindications. Still, if you are living with any of the following conditions, it’s best to avoid added glutamine:

  • Kidney disease
  • Liver disease
  • Reye’s syndrome
  • Seizure disorder
  • Psychiatric disorders

This supplement can also interact with some medications, like lactulose. Even though some trials have shown that glutamine supplementation can help with chemotherapy side effects, other clinical research shows that it may increase tumor production. If you’re living with cancer, talk to your doctor about whether glutamine is safe for you.

If you are elderly, you should reduce your intake of daily glutamine. You should also avoid glutamine supplements if you are pregnant or breastfeeding. Although glutamine supplementation has been used to care for infants and children, consult with a pediatrician before giving them to anyone under age 18.

Are glutamine supplements safe?

Glutamine supplements are generally safe to take for most healthy adults. Studies have illustrated glutamine’s tolerability in doses with strengths up to 45g/day, and most supplements contain 10g per dose or less.

Be aware that some people are allergic to glutamine and may experience side effects, like:

  • Nausea
  • Vomiting
  • Joint pain
  • Hives

If you experience these symptoms after taking a glutamine supplement, seek immediate medical attention and discontinue use.

Daily intake of a glutamine supplement can also result in some mild side effects like bloating, dizziness, upset stomach, or heartburn. If you experience these, lower your dosage or consider stopping supplement use.

The jury is still out concerning the safety of taking glutamine supplements long-term. Most clinical studies administer the supplement for only a few weeks, so we do know that short-term use is considered safe up to about 45g per day, with 5g per day being a more sustainable amount. Since more research needs to be done about the long-term effects, it’s important to stay informed about scientific developments as they happen if you plan to take glutamine for longer than a few weeks.

Revive Glutamine

Best overall and best high dose

Revive Glutamine

Photo by Innerbody Research


  • High 10g dose of glutamine
  • Third-party tested for purity, safety, and dosing accuracy
  • Testing results are publicly available
  • Formula is gluten-free
  • 15% off with a subscription


  • Glutamine test results aren’t yet available
  • No money-back guarantee
  • Strict 15-day return policy

While most companies seem content to provide a 5g serving size for their glutamine supplements, Revive doubles that dose. In most studies we’ve reviewed, 5g is the low end of what scientists investigate as a potentially effective dose. There are some benefits to be had there, but a 10mg dose is closer to those that have been shown to be most effective.

You might ask yourself whether it would be smarter or more economical to just buy a budget supplement with a 5g serving size and double the dose yourself. And that’s not a bad way to get to 10g. But when you look at the scoops that come with these supplements and compare their actual volume, you’ll see that Revive gets a 10g dose out of a nearly identical amount of glutamine powder you need for 5g of its competitors’ products. That becomes important when it comes to the practicality of mixing; a higher strength at the same powder volume allows you to mix Revive’s glutamine powder into something like plain water without as much clouding or as intense of a taste at the 10g dose.

Like many glutamine supplements, L-glutamine is Revive Glutamine’s only ingredient.

Taste and mixability

Revive Glutamine mixed

Photo by Innerbody Research

Revive Glutamine mixes very well into plain water, though it will turn the water a milky white color. It doesn’t settle out much once you’ve mixed it in, and our testers found they could almost entirely mix it with water just by swirling the glass, taking it the rest of the way with a spoon. Considering that milkiness and the typically abhorrent taste of BCAA and EAA supplements, you may not have high hopes for glutamine in general. But we find that this product has a very mild taste that you can obscure with something like a splash of fresh lemon juice or by mixing it into an electrolyte-rich beverage like Gatorade.


Revive has two purchasing options for its glutamine supplement. A one-time purchase costs $20, and a subscription costs $17. There are no bulk discounts.

Here’s what the savings look like when you subscribe:

CostCost per serving
One-time purchase$20$1

These are among the lowest prices for a glutamine supplement, especially when you consider Revive’s impressive 10mg dose. Other companies might cost less per serving, but their 5g serving means you actually get less glutamine for your money overall. And you can cut that dose down to 5g to start if you want to see how the supplement works for you, then increase it to 10g as needed, saving money along the way.

Shipping from Revive is only free for orders of $150 or more. For orders under $150, UPS Ground is your only option, and it’s calculated at checkout.

Revive only gives you 15 days to return a product, and it has to be unopened. No matter the situation, if Revive approves a return, your refund is only given as a gift card to use on its site. This is the weakest aspect of Revive’s service, as competitors like Onnit offer actual money-back guarantees that give you a chance to try the product before sending it back.

Though Revive has room to improve its customer service in terms of a return policy and shipping, this glutamine product rises above the rest.

Transparent Labs BCAA Glutamine Powder

Best pre-workout

Transparent Labs BCAA Glutamine mixed

Photo by Innerbody Research


  • Contains 8g BCAAs for improved exercise performance
  • Includes vitamin C for enhanced immunity and gut support
  • Coconut water powder provides a hydration boost and protects renal health
  • Four flavor options
  • No artificial ingredients
  • Subscribing can unlock free shipping and save 10%


  • Pricier than other options
  • No money-back guarantee
  • Flavors limit mixing options

Transparent Labs BCAA Glutamine Powder is our top pre-workout because it boosts your muscle-building potential by combining the power of glutamine with BCAAs. Those specific amino acids — leucine, isoleucine, and valine — have been shown to reduce muscle soreness after a workout and balance muscle protein synthesis against protein breakdown to ensure you maintain the muscle you have and increase the odds of building more.

In addition to glutamine and BCAAs, the supplement also includes coconut water powder, which helps with hydration and electrolyte balance but also plays a role in kidney health. There is some evidence that amino acid supplementation can negatively impact the kidneys and even lead to the development of kidney stones. But coconut water powder has been shown to work against this. Rounding out the formula is vitamin C, which works hand-in-glove with glutamine’s gut support. While glutamine works to bolster and repair gut linings, vitamin C can help balance out the gut’s microbiome.

Transparent Labs is committed to providing comprehensive ingredient lists to consumers. That’s why its ingredient breakdown includes specific measurements for its “other ingredients,” something we’ve yet to see from any competitor.

Active ingredients

  • Leucine: 4,000mg
  • Isoleucine: 2,000mg
  • Valine: 2,000mg
  • Glutamine: 5,000mg
  • Vitamin C: 1,535mg
  • Coconut water powder: 1,000mg

Other ingredients

  • Citric acid: 1.5g
  • Natural flavor: 1.15g
  • Stevia: 515mg
  • Calcium silicate: 257.5mg
  • Silicon dioxide: 257.5mg

Taste and mixability

Because it contains BCAAs, an unflavored version of Transparent Labs BCAA Glutamine would not be pleasant to drink, so the company provides four flavor options, more than any other product on this list:

  • Sour green apple
  • Tropical punch
  • Strawberry lemonade
  • Blue raspberry

We tried the fruit punch flavor, and it scored around the middle of the pack among other BCAA supplements. Compared to unflavored glutamine supplements, the added taste is a double-edged sword. On the one hand, you get a product that you can easily mix with water and enjoy before, during, or after a workout. On the other hand, your mixing options are more limited than they would be with unflavored glutamine. As for mixability, BCAA Glutamine blends well enough with water, though there is some slight settling out at the bottom of the glass after a while. This is mostly a result of its other ingredients; plain, unflavored glutamine tends to mix better with water.


One tub of powder costs $39.99, which includes a 30-day supply. You can earn free shipping by placing an order over $149 or by subscribing to repeat deliveries. Joining Transparent Labs’ subscription program also saves you 10% on each order ($35.99/tub). Here’s what those subscription savings can look like:

CostCost per servingShipping
One-time purchase$40$1$9

You can choose to have your order auto-shipped every 30, 45, or 60 days.

Transparent Labs offers a 30-day return policy on unopened products for a full refund. If your product is opened, you can still return it within 30 days for a store credit or product exchange.

Kaged Glutamine

Best budget pick

Kaged Glutamine mixed

Photo by Innerbody Research


  • Lowest cost per gram of glutamine on our list
  • 100 servings per container
  • Third-party tested
  • Informed-Sport certified
  • Flexible delivery schedule for subscriptions
  • Free shipping on all orders
  • Subscribing saves you 10%


  • Testing results are not readily available
  • Doesn’t taste or mix as well as other unflavored options
  • Money-back guarantee has some interesting caveats

Often, when we set out to review supplements, we find that Bulk Supplements (a little further down our list) often comes out ahead of the pack in terms of cost. But in the case of glutamine, Kaged managed to edge it out by delivering its product at a lower one-time cost and offering a deeper discount to subscribers.

From a dosage perspective, you could easily titrate up from 5g if you feel you’re not getting results at that level, and the process wouldn’t become prohibitively expensive. The only issue there is, compared to a product like Revive Glutamine, you’re adding a lot of powder to a glass of water or a smoothie. Revive’s more concentrated formula is a little easier to work with and quite a bit easier to drink than Kaged at a 10g amount.

If budget is your primary concern, you likely can’t do better for a product that boasts vegan ingredients, Informed-Sport certification, and third-party testing. Some other companies, like Transparent Labs and Revive, make their third-party testing results readily available on their websites. Kaged subjects its product to third-party testing but keeps those results to itself. (We prefer more transparency.)

Taste and mixability

As we alluded to earlier, a dose-for-dose comparison with Revive Glutamine reveals that Kaged doesn’t mix as well or taste as good as some of the competition. It’s fine for an unflavored option, and it only settles out a little bit into a glass of water. In a thicker drink like a protein shake, you’ll likely never know it was there.

One aspect of the preparation process we appreciated was the length of the Kaged scoop. Most glutamine supplements come with scoops to measure out doses, but these can sometimes be too short to reach the bottom of the container comfortably as it gets close to empty. The scoop that Kaged provides has an elongated handle that makes getting the last bits of glutamine and measuring them accurately easier than with many others.


Among the companies we recommend for glutamine, Kaged Glutamine’s price is the lowest per gram of glutamine. Each container has 500g — 100 5g servings of glutamine — for $24.99. If you subscribe, that cost comes down to $22.49, and you can choose a four- six- or eight-week delivery schedule.

With every other company reviewed here, you have to spend a certain amount of money to get free shipping. In Transparent Labs’ case, you can unlock free shipping with a subscription. But Kaged offered free shipping on all orders, further cementing its status as our top budget pick.

Kaged is the only company here other than Onnit to offer an actual money-back guarantee on its products, but that guarantee has a few wrinkles you should know about before you try to use it. The guarantee period lasts 30 days, but you can’t use more than 50% of a given supplement for it to apply. If you use Kaged Glutamine at a 10g dose for three weeks and then decide to return it, you will be denied.

And not all products from Kaged are eligible for that money-back guarantee in the first place. We double-checked, and Kaged Glutamine is on the list of items eligible for the money-back guarantee, but if you’re thinking about adding anything else to your order, you should check the policy to make sure it’s covered.

Onnit L-Glutamine Amino Acid

Best money-back guarantee


  • Formula contains no added ingredients
  • Affordably priced
  • Informed Sport-certified
  • 90-day money-back guarantee
  • Generous discounts for first responders, military, medical workers, and teachers
  • Subscribe and save 15%


  • Unflavored option only
  • You must spend $150 to earn free shipping

Onnit offers a wide array of health and wellness supplements, many of which focus on cognitive and exercise performance. The company’s central product is Alpha Brain, a nootropic designed to support memory, cognition, and learning.

Onnit’s L-Glutamine Amino Acid is listed among its gut health supplements and contains L-glutamine with no other active ingredients, ensuring you get a pure dose of this potent amino acid. Onnit’s supplement is also Informed-Sport certified, meaning that it’s free from banned substances and not a problem for competitive athletes to use.

Taste and mixability

Onnit performs on par with most unflavored glutamine supplements, dissolving well into water and not tasting like much. Like most other unflavored options offering 5g serving sizes, Onnit’s mix couldn’t quite compete with Revive’s in terms of mix or taste when the doses were equal.


A 60-serving tub of Onnit’s glutamine supplement costs $21.99 to purchase once. You can opt for a subscription to save 15% ($18.69/tub).

Your order will auto-ship every 7-90 days, depending on your preference. Onnit offers free shipping on orders over $150, which appears to be something of a standard for many companies. Only Kaged, Nutricost, and Bulk Supplements have superior shipping policies.

Onnit’s Keep-It guarantee is the main reason most people would gravitate toward this company over another. Onnit doesn’t exactly have the best price, but its guarantee covers all first-time orders. This guarantee allows 90 days to initiate a potential refund if you’re unsatisfied with the product.

Instead of returning the product to Onnit, you get to keep whatever’s left and still receive a refund. However, you’ll need to try out the product for at least two weeks before initiating a refund. Compared to the 30-day policy of Kaged, which prohibits you from consuming more than half a container of glutamine, this system seems more in line with what a customer would actually need.

Bulk Supplements N-Acetyl L-Glutamine Powder


  • Pay as little as $0.03 per gram of glutamine
  • Choose from six product sizes — up to 25kg of powder
  • Free shipping on orders over $59 in the contiguous U.S.
  • Gluten-free formula
  • 30-day return policy
  • Subscribe and save 5% or use code INNERBODY5 to save 5% without subscribing


  • Specific form of glutamine may be less well absorbed
  • Subscription savings are slight
  • Subscribers don’t automatically get free shipping
  • Bags don’t come with scoops (you have to measure with a scale)

Bulk Supplements N-Acetyl L-Glutamine Powder could be a better budget pick than what Kaged offers if you’re willing to spend more up-front. But that minimum investment, which gets you more than 2lbs of glutamine, is likely more than most people need when they’re first starting out. It’s possible that you might end up taking an especially high dose with sufficient regularity (multiple times daily) that Bulk Supplements becomes your go-to pick for savings. We just feel that the average person would be better off starting with the kind of savings Kaged offers with a more modest investment.

One sticking point for Bulk Supplements is that it uses an acetylated form of glutamine (N-acetyl L-glutamine, sometimes called NAG). NAG has a better shelf-life than L-glutamine and is more soluble in water, but some research suggests that it doesn’t absorb into the bloodstream as well as L-glutamine, so dosing may not be equivalent.

Bulk Supplements lists its serving size as 500mg, which is significantly lower than other companies and a lot lower than what we often see used in research. You can easily get a higher dose than this, but if you’re calculating your budget based on servings, this could throw you off a bit. The powder does not contain added sugar, soy, dairy, yeast, gluten, or other additives.

Taste and mixability

As you might have guessed from the brief mention of NAG above, Bulk Supplements N-Acetyl L-Glutamine mixes very well in water. The taste is on par with L-glutamine delivered by other unflavored options from Revive, Kaged, and Onnit. And thanks to its high degree of mixability, you can readily add it to just about any beverage you like to improve the taste.


A one-time purchase of a 100g bag of powder costs $12.96. You can also opt for a subscription purchase and save 5%, which is the smallest subscription savings of the companies in this guide.

Here’s a look at each bulk level and price for one-time and subscription purchases:

One-time purchaseSubscription price
100g (3.5oz)$13$12
250g (8.8oz)$21.96$21
500g (1.1lbs)$30.96$29
1kg (2.2lbs)$50.96$48
5kg (11lbs)$243$231
25kg (55lbs)$851$809

If you choose to join the subscription program, your order will auto-ship every 30, 60, or 90 days. Bulk Supplements provides free shipping on orders over $59 placed in the contiguous U.S. and covers orders with a 30-day return policy. Unopened products are eligible for a full refund, but opened products pose some more risk to your investment. Bulk Supplements will only refund the price of its smallest available unit for any opened product. So, if you spent $50 on a 1kg bag of its glutamine, you could only get $12.96 back as a refund (the cost of the smallest available unit).

Glutamine supplement FAQ

Alternatives to glutamine supplements

Potential alternatives to glutamine supplements may be a better path forward, depending on your particular health goals. The important thing is to identify what those goals are and possibly to consult with your physician to decide which route is best for you, given any potential conditions or contraindications for current medications.

Let’s take a quick look at some alternatives to glutamine supplements and discuss their potential uses. None of these are mutually exclusive to glutamine, so you could also take them alongside a glutamine supplement:

Amino acids

There’s a good chance you’re getting enough glutamine in your diet to maintain good health if you’re already relatively healthy. But if you’re looking for a boost in essential amino acids, these supplements may be a superior option to glutamine alone. Some may even contain conditionally essential amino acids like glutamine. We have a guide to the best amino acid supplements with more information.


If you’re looking to use glutamine as a means to address your gut health, taking a probiotic might be equally effective. You may also want to get your microbiome tested and pay a visit to a gastroenterologist.

Protein powders

For those seeking a way to build more muscle, glutamine and BCAAs have a role to play, but if you have a hard time putting on any kind of weight — fat or muscle — you’ll need more calories in conjunction with protein. Protein powders and mass gainers are great for this, and many contain large amounts of all 20 amino acids, including glutamine. You can learn more about adding muscle in our guide to the best muscle-building stacks.



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