Glutamine is one of the twenty amino acids that are crucial to your body. It’s a building block of the protein molecule and an important component of your immune shield.
Although it doesn’t belong to the essential amino acids since your body can produce it, there are some cases when you may need an additional source of glutamine. That’s where glutamine supplements come in.
In this guide, you will find out what are the best glutamine supplements on the market today and learn the key facts about this amino acid.
- 1 7 Best Glutamine Supplements on the Market
- 1.1 NOW Sports L-Glutamine Powder
- 1.2 Bulk Supplements Glutamine Powder
- 1.3 Body Fortress Glutamine Powder
- 1.4 MusclePharm Essentials Glutamine Powder
- 1.5 Jarrow Formulas L-Glutamine Powder
- 1.6 NOW Supplements L-Glutamine Caps
- 1.7 Pure Encapsulation Glutamine Caps
- 1.8 What Is Glutamine?
- 1.9 What’s the Difference Between L-Glutamine and D-Glutamine?
- 2 Signs of Glutamine Deficiency
- 3 Health Benefits of Glutamine
- 4 Side Effects of Using Glutamine
7 Best Glutamine Supplements on the Market
NOW Sports L-Glutamine Powder
If you’re looking for a trusted glutamine brand with a high-quality product, the NOW Sports glutamine powder can be your choice.
This brand doesn’t use any additives during the manufacturing process and offers you the form of glutamine that is the closest to the one found in foods, for better absorption.
A 500g package contains about 100 servings, so you can use it for at least three months. With one scoop, you will get 5 g of pure amino acids that will begin to work right away. It’s a great option for those who need to take high doses of glutamine for a long period.
Bulk Supplements Glutamine Powder
As the name implies, this may be the best glutamine supplement for people who love buying in bulk and thus saving some money.
One serving contains about 1000 mg of pure 100% L-Glutamine without any additives or fillers. Depending on your diet plan, you may be consuming 3 to 10 servings a day. Thus, the whole 1kg package of this supplement should last at least 3 months.
The only issue you might encounter with this powder is that it might be a challenge for the ziplock package to stay closed, so you may want to store the powder in an airtight container.
Body Fortress Glutamine Powder
Another brand with good value, Body Fortress offers you 4.5 g of pure glutamine per serving. It’s an optimal dose for bodybuilders with a moderate to high level of activity, as well as for those who suffer from glutamine deficiency.
The greatest thing about this supplement is that the manufacturing process meets cGMP standards, which is the sign of the highest quality among all dietary supplements.
The whole package contains about 66 servings so you can use it for two or three months, depending on your needs.
MusclePharm Essentials Glutamine Powder
MusclePharm is among the most well-known supplement brands on the market, and their products usually have decent quality and reasonable prices. This L-glutamine powder is no exception: it’s pure, it comes in the form with better bioavailability, and it will give you 5 grams of glutamine with each serving.
The only downside of the product is that it cannot be considered suitable for people with food sensitivities or dietary restrictions. That’s because MusclePharm uses the same equipment to produce glutamine as it uses for other products, so the powder might contain traces of gluten, eggs, or dairy.
But if you’re not allergic to these foods, you may opt for this brand because it’s reliable and offers products with a balanced formula.
Jarrow Formulas L-Glutamine Powder
This glutamine supplement by Jarrow is totally suitable for vegetarians and vegans.
Even though Jarrow is among the few brands that offer you only 2 grams of L-glutamine per serving, the 1kg package still seems like a good deal. Even if you’re taking a lot more than 1 serving a day, it should last you at least three months.
But for those who don’t plan to take glutamine in high doses, this supplement may be the best option, as it leaves room for flexible dosing.
NOW Supplements L-Glutamine Caps
NOW is one of the best glutamine supplements that come in the form of capsules. It’s standardized and meets the requirements of both cGMP and Natural Products Association, so you can be sure about the quality ingredients inside.
The 500mg capsule allows you to precisely regulate how much L-glutamine per day you want to take based on your needs. There are two bottle sizes available — 120 and 300 capsules, which should be perfectly enough even for people who need additional supplementation during their intensive workouts and recovery.
However, making capsules often requires using additives to form a solid pill. In the case of NOW, there are rice flour, cellulose, and magnesium stearate, which means the product is vegan-friendly but not pure.
Pure Encapsulation Glutamine Caps
Another brand of glutamine capsules, Pure Encapsulation uses plant-derived cellulose to make shells, which makes their product suitable for vegans. It’s also hypoallergenic since the brand is manufacturing the caps on a separate equipment line free from soy, eggs, dairy, and other allergens.
One capsule packs 1000 mg of pure L-glutamine, and the brand’s instructions recommend taking 1 capsule 1-3 times daily. You can choose between 90 and 250 capsule bottles, and there’s also an option with just 500 mg of glutamine per capsule for those who need smaller doses.
Caps are a preferable form of use for those who don’t like how glutamine powder tastes; however, if you need larger doses of this amino acids, it’s advisable to switch to the powder form.
What Is Glutamine?
Glutamine is an amino acid, and amino acids play a bunch of roles in your body. Their main purpose is to serve as parts of a protein molecule, which is crucial for building cells, tissues, and organs.
But the functions of proteins aren’t limited to anabolism only; they can also transport some substances in the blood flow and help you fight pathogens when you get an injury or catch a cold.
What’s the Difference Between L-Glutamine and D-Glutamine?
You may notice that some supplements are labeled as ‘glutamine’ and others ‘L-glutamine’.
So what does the ‘L’ mean and does it makes a product better?
As with all amino acids, there are two types of glutamine: L-glutamine and D-glutamine. The difference between them lies in how the atoms are arranged around the carbon backbone:
- in L-glutamine, nitrogen ‘tails’ are placed on the left side of the molecule;
- the D-glutamine molecule has the same ‘tails’ on the right side.
In nature, the L-form of all amino-acids is predominant, since it’s the form that our bodies can produce or find in foods. D-amino acids can be useful in very rare cases; speaking of glutamine, its D-form just has no nutritional value and cannot be metabolized by your body.
Signs of Glutamine Deficiency
Now, although glutamine is normally produced by our body, it is considered a conditionally essential amino acid. This means that some conditions, such as severe diseases or stress, may lower your ability to produce glutamine. Also, your intestines may sometimes have trouble absorbing different substances. For example, if you have Crohn’s disease, inflammatory bowel syndrome or leaky gut.
In all of these cases, you may feel the main signs of glutamine deficiency, which include the following:
- more frequent colds or infections;
- weight loss;
- lack of energy;
- imbalance of the gastrointestinal system.
You can find out the exact levels of glutamine in your blood by taking blood tests. If the tests show that you lack glutamine, your doctor may prescribe you taking supplements or take on a glutamine-rich diet.
What Foods Are Naturally Rich in Glutamine?
As with other amino acids, almost all glutamine-rich foods are animal-based products. Here are the products you may want to incorporate in your diet to get more glutamine:
- Meat. Beef is the leader when it comes to glutamine, as there are 1.2 grams of this amino acid per 100 grams of beef. However, chicken and lamb are also a good option if you want some variety.
- Seafood. Saltwater fish is also rich in glutamine. Choose salmon or tuna if you need to replenish its levels.
- Dairy. Milk doesn’t have that much glutamine; however, it can boost the production of glutathione, which works as a precursor of this amino acid. Other dairy products rich in glutamine are yogurt and soft cheeses like ricotta.
- Eggs. Although eggs have fair glutamine content, they still can be beneficial for those who exercise in a gym due to the balanced levels of other amino acids.
Vegans can get glutamine from nuts, beans, and such soy products as tofu and leafy greens. However, you need to be aware that heat processing lowers the levels of glutamine in vegetables, so it’s preferable to eat them raw.
“Focus on consuming the needed amount of proteins based on your dietary needs. This way you can potentially increase the chances of getting the right amount of all amino acids, including glutamine.”
Glutamine Release Forms and the Differences Between Them
When it comes to supplementing forms, you can choose between glutamine powder and glutamine capsules.
Each of these two forms has its own features, which are listed below:
- Powder. Glutamine powders usually contain higher doses of this amino acid, which is great for individuals with deficiency or other conditions that require using a more concentrated product. Their only downside is taste, but this is not uncommon in the world of amino acid supplements. However, if you’re sensitive to weird tastes, consider choosing caps or just drink your powder dose mixed with juice.
- Capsules. Glutamine caps will suit people who need to know the exact dosage of amino acid they’re taking or for those who need a moderate amount of glutamine per day. However, the dose of glutamine in capsules is usually smaller than in powder. Also, some capsule shells may be made from gelatine, which makes them unsuitable for vegans.
“Glutamine fluids and solutions are also available; however, they have strict medical use and cannot be considered supplements.”
Health Benefits of Glutamine
So, everyone knows that glutamine is important, just like all amino acids. But why exactly?
Below, there are scientifically proven glutamine benefits that can help you combat certain health conditions and increase overall well-being.
Supports Immune System
Glutamine is beneficial for your immunity.
It serves as a source of fuel for white blood cells and some intestinal cells, along with glutamate and aspartate.
Glutamine can increase the level of B and T-lymphocytes in patients with SIRS (Systemic Inflammatory Response Syndrome). SIRS is a potentially life-threatening condition that may occur after infection, burn or trauma. A study published in the Journal of Critical Care showed that glutamine supplementation improved recovery in all 15 SIRS patients in the glutamine group.
Another study with a sample of 22 patients undergoing colorectal resection also reported an increase of the T-lymphocytes level in the blood during glutamine supplementation.
Your small intestine and bowel are the main organs responsible for both vitality and immunity, from the inside.
Glutamine can be beneficial for you because it:
- Promotes gut cells growth. Your gut needs glutamine to maintain its lining and to grow new cells. Along with that, glutamine also helps transport some nutrients and preserve the intestinal villi (structures that are responsible for absorption).
- Repairs leaky gut. Leaky gut is a condition that has many causes, with the main of them being chronic stress, exposure to radiation, chemotherapy and even hard workouts. In many of these cases, L-glutamine can repair the intestines and prevent them from forming new perforations.
- Improves the gut flow. Glutamine has shown to be helpful in improving gut motor activity in patients with gastric surgery. According to this study, the group of patients who were taking 3 grams of glutamine for 12 days eventually had better gut flow compared to the placebo group.
Provides Liver Detox
One of the recent discoveries that seem very promising is the benefits of glutamine for the condition called hepatic steatosis (also known as ‘fatty liver’). People with hepatic steatosis are prone to building up fat in their liver cells, which can result in inflammation and enlargement.
So, what does glutamine do to liver cells?
A study conducted on rats with pancreatic atrophy and hepatic steatosis showed that glutamine supplementation reduced the percentage of fat in a fatty liver by 47% and the overall liver weight was also decreased by 12%.
Researchers believe that they can scale this model on a human sample in the nearest future.
Aids in Recovery and Regeneration
White cells, such as lymphocytes and macrophages, are not only important for your immune system but also play a great role in the wound healing process.
In fact, when you receive a severe trauma, the levels of glutamine in your blood might drop too low to promote proper regeneration. Thus, your body needs to break down the muscle fibers to compensate for the glutamine deficiency. Supplementation during the recovery process may help you avoid that and may shorten your hospital stay.
Glutamine for Bodybuilders: Scam or Legit?
Hard training in the gym, in some cases, might require using additional supplementation with some essential micronutrients, such as amino acids, hormones, vitamins, and minerals.
However, the use of glutamine in bodybuilding is a rather controversial topic because researchers can’t agree with its effectiveness in building lean muscle mass.
According to the study published in the American Journal of Physiology, glutamine supplementation increases the levels of this amino acid in the blood, but its levels in the muscle tissue remain unchanged.
Still, glutamine supplementation may help professional athletes who tend to have lowered immunity because of overtraining. For example, it may help them avoid catching a cold.
Some researchers also report that glutamine might decrease muscle soreness and speed up the recovery time after the intensive training.
What Is the Right Glutamine Dosage for You?
Since glutamine is the amino acid naturally found in our bodies, it’s obviously safe when taken in adequate amounts.
However, the FDA does not regulate the production of the supplements and hence does not give recommendations as for the dosages. Since your goals, diet, duration of the supplementation period, as well as many other factors, should be counted in, finding the right glutamine dosage might seem a challenge.
Yet, scientists have managed to calculate optimal doses for different needs:
- a typical balanced diet may contain 3 to 6 grams of glutamine per day, although this can vary depending on the type of foods you consume;
- although some studies show a vast range of potentially safe doses starting from 5 g per day up to 45 grams per day for 6 weeks, it isn’t recommended to exceed the dosage of more than 10 grams per day due to the increased ammonia in the blood serum;
- the lowest dose of glutamine found to increase ammonia is 0.75 grams per 1 kg or about 50 grams for a person weighing 150 lbs;
- for strengthening your immune system, take one 5g serving after waking up and another one before bed.
All experts consider starting from lower doses and gradually increase them if you don’t feel the effect.
“If you need to count the right dosage of glutamine for long-term supplementation, it’s best to address this request to your doctor.”
Side Effects of Using Glutamine
Each supplement along with benefits for your health will have some side effects.
The typical glutamine side effects include the following:
- Reduced production of internal glutamine. Any synthetic supplementation can impair the production of nutrients by your body. Glutamine is no exception in this case.
- Ammonia build-up. Ammonia is the byproduct of glutamine absorption, and it’s harmful to our liver and kidneys. Long-term glutamine supplementation can impair the ability to detoxify ammonia and affect its transportation between tissues.
- Withdrawal symptoms. Since the body may reduce producing its own glutamine during the supplementation period, you may experience slight withdrawal symptoms after finishing taking the supplement. These symptoms may include dizziness, headaches, and nausea.
Glutamine supplementation may also slow the absorption of other amino acids and lead to the increased acidic levels in the blood.
“Consider all the pros and cons before taking each supplement and consult with your doctor before making any changes to your regular diet.”
FAQ for Glutamine Buyers
What drugs may interact with glutamine?
Although glutamine is considered safe, there are a couple of drug interactions you should be aware of:
- Lactulose. Lactulose helps decrease the levels of ammonia in the body, whereas the main metabolite of glutamine is ammonia. Thus, taking these two substances together might decrease the effectiveness of the lactulose.
- Anticonvulsants. Anti-seizure medications may affect the chemical balance in the brain. Glutamine, while being a component of some neurotransmitters, may decrease the efficiency of anticonvulsants.
- Cancer medications. Some researchers believe that glutamine may decrease the efficiency of some cancer medications; however, there isn’t enough data on this.
When to take glutamine for the best effect?
The most optimal time for taking glutamine depends on your goals.
If you’re taking it for gut health, the best time is 30-45 minutes before each meal. For speeding up the recovery time after training or surgery, it is advised to take glutamine between meals.
How long should I take glutamine?
Most studies show that glutamine has been totally safe for taking in the short term (up to 6 weeks); however, there isn’t enough data for the long-term effects.
If you’re concerned about breaks in your glutamine supplementation course, the best advice would be to consult your doctor.
Can I use BCAA or other amino acids with glutamine?
It’s up to you and depends on your particular situation. But according to science, some amino acids may compete with others for absorption and transportation to the body tissues. Speaking of glutamine, it can interfere with other amino acids or even cause their depletion.
Glutamine is a conditionally essential amino acid that is produced by your body and can be naturally taken from different foods.
However, supplementing yourself with glutamine can be beneficial under certain conditions, such as severe trauma, surgery, or post-workout recovering.
A regular diet usually estimates an optimal dose from 3 to 6 grams of glutamine per day, but you can change your dosage under the guidance of your healthcare practitioner.
Although there isn’t enough evidence for the safety of taking glutamine long term, this amino acid appears to be totally safe in short supplementation courses.