Known as the “building blocks of protein,” amino acids are popular choices for athletes looking to get an extra boost at the gym. However, even among these health powerhouses, glutamine manages to stand out.
Glutamine is an amino acid found in high levels throughout the body, particularly in skeletal muscle. Even with these large concentrations, additional glutamine is remarkably effective in improving everything from muscle growth to mental focus.
If you use it the right way and for the right purposes, there’s no reason why glutamine shouldn’t benefit you too.
Glutamine’s Role in the Body
Glutamine is the most common amino acid in muscle tissue. Because it’s derived from glutamic acid, glutamine is considered a non-essential amino acid, though it can be derived from other sources.
When glutamine levels are balanced, the body uses glutamine to control blood sugar levels, maintain muscle mass, and improve mental function. Glutamine is also the only non-essential amino acid able to cross the blood-brain barrier. For these reasons, glutamine is considered both a “brain food” and a muscle builder.
Glutamine’s primary role in the body is to aid in DNA and protein synthesis. With glutamine, your body is able to manufacture muscle cells. This is especially helpful after intense physical exercise, when glutamine rebuilds muscle. And, if you’re in a calorie surplus, glutamine rebuilds larger muscle.
Glutamine also produces nitrogen and carbon to fuel new cells and support the immune system, particularly in the gut.
Potential Glutamine Benefits
Although the body generally produces enough glutamine for normal day-to-day life, some people choose to take a glutamine supplement for additional benefits.
Here’s a look at just a few of the benefits a glutamine-based supplement can provide.
- Concentration: So-called “brain fog” may be alleviated with glutamine supplementation. Glutamine is a pre-cursor for GABA, which functions as an inhibitory neurotransmitter and enhances concentration and mood stability. Tellingly, children with ADHD often have low glutamine levels in their blood.
- Muscle Recovery: Stressing the muscles in exercise or other activity causes damage. Glutamine responds by transporting nitrogen atoms to create a positive nitrogen balance, which stimulates tissue repair. To guard against future damage, glutamine rebuilds bigger muscle, which promotes size and strength.
- Growth Hormone Production: Some evidence suggests glutamine increases growth hormone production. Growth hormone provides powerful anti-aging benefits as well as increased muscle growth and power. In one study, glutamine triggered higher circulating growth hormone levels within 90 minutes of ingestion.
- Weight: Glutamine also has profound effects on weight loss. Because it controls blood sugar levels, it moderates appetite and, in high doses, curbs cravings between meals. Glutamine may also increase caloric expenditure, supporting fat burning. In an animal study, mice fed glutamine burned 42 more calories than the control group and experienced greater weight loss.
- Healing Traumatic injuries: Injuries such as infections, burns, surgical procedures, or trauma causes the body to become stressed and release high cortisol amounts into the bloodstream. Because cortisol lowers glutamine stores, it’s necessary to add glutamine to balance hormone levels in the body. This strengthens the immune system, reduces infections, and prevents tissue death in the case of burns.
These benefits are available for anyone who takes glutamine, though people with liver and kidney problems should talk to their doctors first. This is because people with liver and kidney damage are unable to properly process glutamine.
Side Effects with Glutamine
Glutamine is considered “possibly safe” for most users by WebMD in dosages lower than 40 grams daily. However, some mild side effects may plague users who are sensitive or unused to high glutamine levels.
The most common glutamine side effects include nausea and diarrhea. If these occur, lower your glutamine dosage until you achieve a proper balance between effectiveness and safety. You should also drink plenty of water to avoid dehydration.
Using Glutamine Effectively
To gain these glutamine benefits, take up to 20 grams a day. Most people choose to divide this amount into 5 to 10 gram servings taken two or three times throughout the day. You can take a glutamine supplement or tailor your diet to include more glutamine.
Remember, however, that optimum glutamine use depends on your health goals. Glutamine dosages for improving mental focus differ from glutamine dosages recommended for muscle growth, for example.
The best way to ensure you’re getting the right glutamine dosages at the right times is to invest in a glutamine-based supplement. These supplements come with usage instructions from the manufacturers on how to get the most from your supplement.
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-  Opara, Emmanuel C., Ann Petro, Allyson Tevrizaian, Mark N. Feinglos, and Richard S. Surwit. 1996. L-glutamine supplementation of a high fat diet reduces body weight and attenuates hyperglycemia and hyperinsulinemia in C5BL/6J mice. Journal of Nutrition: Vol. 126, Issue 1.
-  Landau-Halpern, Beth. 21 February 2012. Amino Acids and ADHD. Accessed 1 May 2013.