Glutamine Benefits: Quick Summary
Wondering if glutamine is worth taking? Here's what you need to know:
Glutamine is the most abundant amino acid in your body. It plays a big role in muscle recovery, gut health, and immune function (1, 2).
Your body produces glutamine naturally, but levels can drop in times of intense training, stress, or illness (3).
Supplementing with glutamine may help support:
• Reduced muscle breakdown
• Muscle growth and recovery
• Immune health
• Gut health and digestion (1, 2, 4, 5)
Many people get enough from protein-rich diets, but athletes and active people may benefit from extra supplementation (6).
The Bottom Line: Glutamine isn't always necessary, but during hard training, stress, or illness, it can become conditionally essential (3). Glutamine supplements can help support your daily glutamine intake.
If you've been training for any amount of time, you've probably heard about amino acids. They're the building blocks of protein ... and your body needs them for just about everything from building muscle to keeping your immune system running strong.
One amino acid that doesn't get enough attention? Glutamine.
It's actually the most abundant amino acid in your body, and it plays a huge role in muscle repair, immune health, and even gut function. I've been using glutamine for years, especially when I'm pushing hard in the gym or fighting off a cold ... and I've seen firsthand what a difference it can make.
But here's the thing: while your body does produce glutamine naturally, research shows it can become "conditionally essential" during times of high stress, heavy training, or illness. That means your body may not be able to make enough on its own when you need it most (3).
So the question is ... do you actually need a glutamine supplement?
In this article, I'll break down what glutamine is, how it works in your body, the benefits you can expect, and whether or not supplementing makes sense for your goals.
In This Article:
• What Is Glutamine?
• How Glutamine Works in the Body
• Food Sources of Glutamine
• Glutamine Benefits
• Glutamine and Exercise Performance
• Do You Really Need Glutamine Supplements?
• Glutamine: Frequently Asked Questions
What Is Glutamine?
Glutamine is classified as a "nonessential" amino acid, which means your body can produce it on its own. But don't let that label fool you ... it's still incredibly important, and there are times when your body can't keep up with demand.
That's why glutamine is often called "conditionally essential." During periods of intense training, high stress, or illness, your body burns through glutamine faster than it can produce it (3).
Most of your glutamine is stored in muscle tissue, but it's also found throughout your body ... in your blood, gut lining, and immune cells. It's one of the hardest-working amino acids you've got.
Now, there are actually two forms of glutamine:
L-Glutamine: The form your body uses for all the critical functions we're going to talk about.
D-Glutamine: This form doesn't play a meaningful role in the body and is mostly used in lab settings.
When you see glutamine listed in foods or supplements, it's always L-glutamine. That's the one we care about.
How Glutamine Works in the Body
Glutamine isn't just sitting around doing nothing. It can help support several key functions in your body:
Protein Synthesis: Glutamine acts as a building block for new muscle tissue (1).
Immune Cell Fuel: Your immune cells, like macrophages, use glutamine as their primary fuel source to defend your body from illness (2).
Gut Lining Support: Glutamine helps maintain the integrity of your intestinal barrier, keeping harmful bacteria and toxins from leaking into your bloodstream (2).
Because of these roles, your body's demand for glutamine skyrockets during times of stress, sickness, or intense training. If you're not getting enough from food or your body can't produce enough on its own, that's when supplementation can be helpful.
When I'm training heavy or feeling run down, adding extra glutamine really seems to help me bounce back faster.
Food Sources of Glutamine
The good news is that glutamine is found in a lot of high-protein foods. If you're eating a solid diet with plenty of protein, you're already getting some glutamine naturally.
Here are some of the best food sources that contain glutamine:
| Source | Protein (Per 100g Serving) |
| Beef | 1.2 g |
| Eggs (Large) | 0.7 g |
| Skim Milk | 0.3-0.7 g |
| White Rice | 0.3 g |
| Corn | 0.4 g |
Now, here's where it gets interesting ... whey protein and casein are loaded with glutamine. In whey protein isolate, for example, you could be getting 15+ grams of glutamine per 100 grams of protein powder.
That's a pretty significant jump! So if you're already using a quality protein powder, you could be getting a solid dose of glutamine without even thinking about it.
But if you're training hard, under a lot of stress, or dealing with illness, you may benefit from adding extra glutamine on top.
Glutamine Benefits
So what can glutamine actually do for you? Research suggests that glutamine supplementation may help support:
Reduced Muscle Breakdown
Glutamine can help protect your muscle tissue from being broken down during intense training or calorie deficits (1). When glutamine is depleted, the body may start breaking down muscle tissue to get the amino acids it needs.
Muscle Recovery
Studies show glutamine can help reduce soreness and speed up recovery after tough workouts (4). Without enough glutamine, your muscles take longer to repair and rebuild (9).
Some studies even show that glutamine supplementation can shorten hospital stays after major surgeries (7).
Immune System Function
Your immune cells rely heavily on glutamine, especially during periods of stress or illness (2). In fact, immune cells prefer glutamine over glucose (sugar) as their primary energy source. When you're sick or under stress, your immune system is working overtime ... and it needs a lot of glutamine to keep functioning properly.
Ever notice how you're more likely to get sick after a really intense training block? Low glutamine levels could be part of the reason (6).
Gut Health and Intestinal Barrier Strength
Glutamine can help support a strong gut lining, which is critical for digestion, nutrient absorption, and overall health (5). Your intestinal barrier is like a gatekeeper ... it lets nutrients in and keeps harmful bacteria and toxins out. Glutamine can help support the integrity of that barrier.
I personally take extra glutamine when I'm sick because I know my immune system is working overtime and needs all the support it can get. I also know plenty of people who swear by it as part of their post-workout recovery routine.
Either way, glutamine has a wide variety of benefits and use cases. It's one of those supplements that might not seem flashy, but it can help support your goals behind the scenes.
Glutamine and Exercise Performance
Here's something you may not know: there's more glutamine in your muscles than any other amino acid. Your body uses it constantly for recovery, immune function, and even energy production during intense exercise (9).
During hard training sessions, your body burns through glutamine faster than it can produce it. When glutamine levels drop too low, you may experience weakened immune function, slower recovery, and increased muscle breakdown (6).
I've definitely felt this myself ... there have been times when I was pushing really hard in the gym, not paying attention to recovery. Then I'd end up feeling run down and sore for days. But adding glutamine to my routine in these times has definitely helped me bounce back faster.
Do You Really Need a Glutamine Supplement?
Here's the honest answer: if you're eating a high-protein diet and already using quality protein supplements ... you're probably getting a decent amount of glutamine naturally. You don't have to use a standalone glutamine supplement.
Personally, I believe glutamine supplementation can be helpful if you:
• Train often and with high intensity
• Are under a lot of stress (physical or mental)
• Are recovering from illness or injury
• Want to support gut health and immune function
• Feel like your recovery is lagging or you're getting sick more often
I don't take glutamine every single day. I just keep it on hand and use it when I need it most. If I'm sick, if I'm in a really heavy training phase, or if I'm feeling run down ... I'll add 5 grams of glutamine to my post-workout shake or take it before bed.
Glutamine: Frequently Asked Questions
Q: Is Glutamine Safe To Take Daily?
Yes, when taken in moderate doses like 5 grams per day, glutamine is considered safe. It's a naturally occurring amino acid found in many protein-rich foods that people eat every day.
If you have any medical conditions or are taking medications, it's always a good idea to check with your doctor before adding any new supplement to your routine.
Q: How Much Glutamine Should I Take?
A typical dose of 5 grams per day is considered optimal. Some studies have used doses as high as 20-30 grams per day for short periods (up to 2 weeks) with no negative effects in healthy adults (6).
That said, I'd recommend sticking with 5 grams per day for daily use. If you want to go higher for a short period (like during a really intense training block), that's probably fine ... but I wouldn't do it for more than a couple of weeks, just to be safe.
Q: Can Glutamine Help Support Weight Loss?
Glutamine isn't a fat burner, but it can support weight loss in a few ways. Some studies show it may help the body favor fat loss over muscle loss in obese individuals (8).
It's not a magic solution, though. If you're trying to lose weight, your diet and training need to be dialed in first. No supplement will make results happen without proper nutrition and exercise.
Q: Do I Need Glutamine if I Already Take Protein Powder?
If you're already getting enough protein from food and a quality protein powder, you may not need extra glutamine. But adding it could still be beneficial during times of intense training, high stress, or illness.
Think of it as an extra layer of support ... not required, but helpful when you need it most.
The Bottom Line on Glutamine
Glutamine is one of the most abundant amino acids in your body, and it plays a critical role in muscle growth, recovery, gut health, and immune function. It's a big deal ... even if it doesn't get as much attention as other supplements like creatine or protein powder.
For most people, a protein-rich diet is enough to maintain healthy glutamine levels. But if you're training hard, under stress, dealing with illness, or want to support your recovery and gut health ... supplementing with glutamine may be helpful.
At 1st Phorm, our mission is to help real people earn real and long-term results. We know you don't take shortcuts with your health and fitness goals. That's why we don't take any shortcuts with the products to help support your goals.
For glutamine supplements, we offer a pure, Micronized Glutamine Powder. It's flavorless, mixes well, and contains a full 5 grams of L-Glutamine in every serving!
We also have a wide variety of protein supplements that contain glutamine for additional support.
Now, I know we covered a lot today. That said, if you have any questions about glutamine, supplements, or even just your goals ... Don't hesitate to reach out to us. We have a full team of NASM Certified Personal Trainers and Nutrition Coaches right here in St. Louis, Missouri.
Just give us a call at 1-800-409-9732 or send us an email at CustomerService@1stPhorm.com. We're available Monday through Friday from 6 AM to 8 PM Central and Saturday & Sunday from 9 AM to 7 PM Central.
We'll be more than happy to help in any way we can!
References:
(1) Córdova-Martínez A, et al. Effect of Glutamine Supplementation on Muscular Damage Biomarkers in Professional Basketball Players. Nutrients. 2021;13(6):2073.
(2) Perna S, et al. The Role of Glutamine in the Complex Interaction between Gut Microbiota and Health: A Narrative Review. Int J Mol Sci. 2019;20(20):5232.
(3) Lacey JM, Wilmore DW. Is glutamine a conditionally essential amino acid? Nutr Rev. 1990;48(8):297-309.
(4) Legault Z, et al. The Influence of Oral L-Glutamine Supplementation on Muscle Strength Recovery and Soreness Following Unilateral Knee Extension Eccentric Exercise. Int J Sport Nutr Exerc Metab. 2015;25(5):417-26.
(5) Achamrah N, et al. Glutamine and the regulation of intestinal permeability: from bench to bedside. Curr Opin Clin Nutr Metab Care. 2017;20(1):86-91.
(6) Gleeson M. Dosing and efficacy of glutamine supplementation in human exercise and sport training. J Nutr. 2008;138(10):2045S-2049S.
(7) Novak F, et al. Glutamine supplementation in serious illness: a systematic review of the evidence. Crit Care Med. 2002;30(9):2022-9.
(8) Laviano A, et al. Glutamine supplementation favors weight loss in nondieting obese female patients. A pilot study. Eur J Clin Nutr. 2014;68(11):1264-6.
(9) Curi R, et al. Molecular mechanisms of glutamine action. J Cell Physiol. 2005;204(2):392-401.
