Does Glutamine Benefit Every Part of Your Body?

Your body relies on amino acids, the building blocks of protein. They play a role in almost every system throughout your body. The most abundant amino acid in your body is glutamine, and luckily, your body makes most of what it needs on its own. 

Glutamine is a key fuel for the cells lining your gut and for immune cells, and it also has a significant role in carrying nitrogen around your body. However, most people get plenty from food and their own production, so the real question is whether extra glutamine from a supplement helps. For most uses, the evidence so far says no.

What exactly is glutamine?

As we mentioned before, it is the most abundant amino acid in your body. L-glutamine is the form of glutamine that our bodies use daily. Many people are familiar with this supplement, especially athletes and gym enthusiasts, but they mostly use it to enhance their exercise performance. However, scientific research hasn’t shown that glutamine supplements build muscle or strength in healthy people.

It’s not an essential amino acid, but some people label it as conditionally essential. In most cases, your body will be able to produce an adequate amount of glutamine, but there will be times when the amount of this amino acid in your body won’t be enough. This can happen during severe illness, major injury or surgery, which is when doctors sometimes give it, under supervision. 

Are there signs of glutamine deficiency?

There’s no recognized list of glutamine-deficiency symptoms for healthy people, and no home test. Anxiety, cravings, gut trouble, slow recovery and slow-healing wounds can be indicators of a variety of problems, so it’s advisable to visit your doctor rather than self-treat with a supplement.

Here's what you should know about glutamine benefits

1. Glutamine and metabolism

That amino acid is well known for being a vital metabolic fuel.  

Glutamine is a main fuel for the cells lining your gut, which is why scientists study it in seriously ill patients. We found little evidence that supplements improve digestion in healthy people. However, keep in mind that excess amounts of glutamine can be harmful. High doses have been linked to liver and kidney injury in case reports, so don’t take more than your doctor recommends. 

2. Glutamine and muscle building

One of the main goals of most athletes and fitness enthusiasts is to increase mass and tone muscles. Many of them swear by glutamine, but the research hasn’t found that supplements increase muscle mass or strength in healthy people. And keep in mind that your muscle isn’t mostly glutamine, despite what you may have heard. Glutamine makes up about half of the body’s free amino acids, the small pool floating in your blood and tissues, not half your muscle.

3. Can glutamine boost immunity?

Glutamine is vital for your immune system. However, during your weakest moments, your body may not be strong enough to produce the desired amounts of amino acid. Immune cells use glutamine as fuel, but we found no good evidence that supplements prevent or shorten colds in healthy people. Protein foods such as seafood, meat and dairy supply glutamine naturally. 

4. Does glutamine promote brain health?

Your brain converts glutamine into glutamate, a chemical messenger, and back again. Keep in mind that they’re different substances, so don’t mix them up when you read a supplement label. Unfortunately, we found no good evidence that glutamine supplements improve mood, memory or brain aging.

5. Muscle-wasting in people with HIV

Scientists are still struggling to find a cure for HIV. However, they are doing their best to make the lives of HIV patients a lot better and easier. These people often experience a loss of lean tissue mass, and as time passes, people lose more without being able to regain what’s lost. A few small studies have tested glutamine, usually alongside other nutrients, for HIV-related weight loss. It isn’t standard care, so talk to your HIV provider before adding supplements.

6. Recovery after surgery

After major surgery, doctors sometimes add glutamine to hospital nutrition support, and some studies suggest it may reduce the time you spend lying in a hospital bed, though results are mixed. However, keep in mind that it’s a decision for your surgical team, so don’t start any supplement around surgery without asking them.

Conclusion

Most healthy people won’t have to take a glutamine supplement at all, since your body makes it and food supplies it. Don’t forget to talk to your doctor before you start including amino acids in your diet, because they can give you more advice and recommendations in case you need them. 

Meat and some dairy products contain a generous amount of glutamine. You can also find it in some vegetables, such as cabbage, beets, spinach, and brussels sprouts. Fermented foods such as miso paste can also provide a fair amount of this amino acid.