L-Glutamine | What Is It & What Does It Do? Benefits & Side Effects

Glutamine is produced by the body and available in everyday foods, but is also a popular supplement due to its variety of potential health and performance benefits. 

Glutamine exists in two different forms, L-glutamine and D-glutamine, which only vary in molecular structure. In this article, we will focus on the specific health benefits and side effects of L-glutamine.

What is Glutamine? 

Glutamine, specifically L-Glutamine, is an amino acid (a building block of protein). Amino acids and proteins play many vital roles in our body. Specifically, glutamine helps with the transport of carbon and nitrogen (used for cell division and growth) in our bodies and plays roles in neural function, intestinal function, and boosting our immune system. 

It is made by the body in our muscle tissue and is therefore considered “non-essential”. This means that we don’t have to strictly consume it from our diet. However, when our body is under physical (metabolic) stress, it may require more glutamine than it makes on its own. 

This need for additional glutamine, when our body is using it in higher amounts, supports the argument that L-glutamine is actually “conditionally essential” – meaning there are times when it’s necessary to consume more than what our body produces. 

It makes sense that making our muscles work hard would demand more L-glutamine – since they’re responsible for creating it in the body. Instances during which our body comes under stress, makes it require additional glutamine. 

Food Sources 

Dietary sources of L-glutamine include a variety of foods, from animal foods like eggs and beef to vegetable sources like rice or corn. Due to this wide availability in food, following a healthy diet can provide adequate L-glutamine for most people. However, during exercise, L-glutamine production changes based on the type and intensity of activity. 

Because L-glutamine is crucial for muscle building, increasing our levels via supplementation after exercise can be beneficial. L-glutamine supplementation may have a greater benefit on those who have less protein in their diets, like vegans or vegetarians. This is because they may naturally have less of this amino acid. 

Many sports supplements are targeted towards strength training, but L-glutamine has potential benefits for both power exercise and endurance exercise.

Benefits 

Quick Recovery 

Research has shown that athletes can benefit from L-glutamine supplementation to decrease muscle soreness and faster recovery time. 

This amino acid plays a crucial role in controlling glucose (energy) uptake by the muscles after exercise, which can help restore their energy stores for your next workout. When your muscles have optimal glucose stores, you can perform better and take longer to fatigue. 

Long periods of strenuous training have been shown to decrease blood glutamine levels, making it a potentially useful supplement for your post-workout nutrition plan. 

Increased Lean Body Mass and Power 

When combined with creatine, L-glutamine supplementation has been shown to increase lean body mass and power with endurance exercise. 

Studies have shown additional potential benefits, such as: 

• Limited strength loss and reduced muscle soreness
• Feeling less fatigued
• Longer time until exhaustion in endurance exercise

Boost in Immunity 

Additionally, athletes who follow intense training schedules tend to have weakened immune systems due to the constant physical stress of high-intensity exercise. 

Dosage 

Intakes of 20-30g of glutamine or 0.65g/kg of body mass have been used in research studies and not shown any ill effects in short term use. However, you likely only need 3-5g daily to meet your body’s needs. 

Myprotein offers several glutamine options - follow the packaging dosage to use 1-2 scoops per day.