Is Glutamine Good for Muscle Growth?

If you’re trying to build muscle, you’ve likely read about many different supplements that may be able to help. However, it can be difficult to weed out what supplements actually work and what may be a waste of your money. 

When it comes to glutamine, you want to take a second look. 

Glutamine supplements may help boost muscle growth and improve post-exercise recovery in addition to various other health benefits. Read on to learn more.

What is Glutamine?

Glutamine is a type of amino acid, which are the building blocks for protein. 

Our body naturally produces all the glutamine it needs on its own; however, under certain circumstances, our needs may be increased higher than what our body can make. We can also obtain glutamine from foods or supplements [1].

Is Glutamine an Essential Amino Acid?

Glutamine is considered a non-essential amino acid as our body can make it on its own. However, there are many situations in which glutamine may become conditionally essential, such as during critical illness. 

This is because your body requires more glutamine than it can produce when under stress. Supplementing glutamine or consuming a glutamine-rich diet during this time can be essential in recovery [2].

How Does Glutamine Work in the Body?

Glutamine is made from glutamate and ammonia and it is mainly produced in the muscle tissue (about 90%). Glutamine can also be found in small amounts in the brain and lungs. It is essential for helping make the neurotransmitters glutamic acid and gamma amino-butyric acid (GABA) which play a role in our brain health [3, 4].

Glutamine has many different functions in the body but its main role is in the building of proteins. Your body makes glutamine to contribute to the other amino acids necessary to create proteins for your body to use.

Glutamine is also needed to help create other amino acids as well as glucose. Additionally, glutamine is a necessary substrate for protein synthesis and an anabolic precursor for muscle growth. 

It is essential in helping with pH balance in the kidneys as well as an essential component for the functioning of our immune system and digestive health [5, 6].

Does Glutamine Help With Endurance?

Glutamine has become an interest to researchers looking at improving endurance in endurance athletes because blood levels of glutamine drop during long bouts of intense activity, such as running a marathon or triathlon. When glutamine levels are low, muscle recovery may be halted.

Studies found that glutamine supplementation in these populations did help with some common causes of fatigue by improving glycogen synthesis and reducing the accumulation of ammonia in the muscle tissue; however, no studies found any significant improvements in performance itself [7].

While it won’t harm you to take glutamine supplements as an endurance athlete, it won’t likely show any noticeable improvements in your performance levels.

Does Glutamine Help With Muscle Growth?

Glutamine works as a precursor for protein synthesis which means it is required for our cells to make protein to build and repair muscle tissue. Because of its role in protein synthesis, glutamine is also considered an anabolic precursor to muscle growth. 

Studies have found that an increase in glutamine in the muscle cells is linked to increasing muscle cell volume. This helps to enhance protein synthesis and increases muscle size. It may also improve strength by increasing the contractile force of the muscle [8].  

What are the Best Foods With Glutamine?

Glutamine can be found in many different foods but it will be found in the highest amounts in good sources of protein such as meat, fish, poultry, eggs, and dairy products. Other non-animal sources of glutamine include tofu, white rice, and corn [9].

It’s difficult to analyze the exact amounts of glutamine found in these foods. If you are trying to get a rich source of glutamine in your diet, it’s best to focus on getting adequate protein throughout the day rather than just include glutamine-rich foods. 

Is it Beneficial for Athletes to Take Glutamine?

Because glutamine is associated with positive benefits for muscle growth and recovery, it could provide benefits to athletes. 

Glutamine is stored in your muscle tissue. During physical stress, such as intense exercise, glutamine is released. Having higher amounts of glutamine may help to increase the synthesis of new muscle tissue as well as improve post-exercise recovery. 

While some studies support glutamine supplementation for these benefits, others found no significant improvements. While promising, further research is still needed on the potential benefits of glutamine supplementation for muscle growth [8, 10].

With that said, many research studies support adequate protein intake as the biggest necessity for muscle growth when combined with resistance exercise. Because glutamine is an amino acid, consuming a diet rich in protein foods can help to support muscle growth, whether that includes high amounts of glutamine or not [11].

Glutamine Powder vs Pill: Which is Right for Me? 

If you are interested in adding glutamine supplements to your routine, they can be found in a variety of forms. Powdered glutamine supplements are the most common and can easily be mixed into liquids or foods for convenience.

Glutamine is also available in pill or tablet form for those who don’t like powders; however, its form may take longer to digest, especially if there is a coating on the outside. Powdered glutamine is likely absorbed quicker and more efficiently. 

Since it’s recommended to take glutamine shortly before working, it may be more beneficial to take a powdered form for rapid absorption. However, the exact form of glutamine you choose for your supplement depends on your preference.