What Is Glutamine?

While sometimes used interchangeably, “L-glutamine,” and “glutamine” are technically different. Getting into the nitty gritty science of it–glutamine is the amino structure built and used by our bodies, while L-glutamine is something called an “isomer,” which is a molecularly similar but rearranged version of glutamine that can be found in foods we eat. When we consume L-glutamine, in either food or supplement form, our body can rearrange the molecules to create glutamine in our body.

L-Glutamine-Rich Foods

When incorporating L-Glutamine into your diet, you will find many protein-rich foods and vegetables to be your best bet. (1)

Proteins rich in L-glutamine:

• Beef
• Milk (Skim milk is especially rich in L-glutamine)
• Eggs
• Yogurt (Greek yogurt is especially rich in L-glutamine)
• Tofu 
• Cottage cheese
• Ricotta cheese

Vegetables rich in L-glutamine:

• Raw spinach
• Raw parsley
• Broccoli
• Kale
• Cabbage

Health Benefits of L-Glutamine

The benefits of L-glutamine are varied and far reaching, making it an excellent multi-effect supplement. Anything that supports overall gut health is a no-brainer for overall wellness, but its effects on athletic recovery and in specific medical applications can be incredibly useful as well.

1. It supports your gut 

L-glutamine has been well-proven to support our gut barrier and lining, as well as promoting gut microbiome diversity (more types of good bugs in our gut). (2) 

For individuals struggling with leaky gut syndrome and its symptoms, L-glutamine has the potential to be an incredible healing agent.  

Virtually everyone can benefit from making choices supporting of their gut microbiome, prioritizing both prebiotics and probiotics in their daily routines, be it dietary or in supplement form. Supplementing with L-glutamine can help those pre and probiotics do their job better and provide more lasting benefits.

2. It can help you recover from your workouts quicker

While it’s somewhat intuitive that an amino acid, a building block for muscle, would help in athletic applications, the theory also holds up to science where recovery is concerned. Quite a few studies have confirmed that L-glutamine supplementation can offer a variety of benefits in this area. (3)

• Glutamine supplementation reduces markers of muscle damage in high-performance athletes
• It seems to help increase muscle mass when taken over time.
• Its use has been observed to be associated with better athletic performance overall, but current studies can’t adequately attribute L-glutamine alone in this benefit.

3. Weight and fat loss

Individuals hoping to lose weight or improve metabolic function may find L-glutamine a helpful supplement in their journey. L-glutamine can increase the circulation of glucagon-like peptide-1 (GLP-1), the very same effect that new popular weight loss drugs like semaglutide have on the body. (8) Additional GLP-1 in the body helps regulate insulin production and blood sugar to make people feel more satiated after meals. Studies have confirmed this effect in a clinical study observing the effect of L-glutamine on non-dieting obese females. (7)

Additionally, it’s important to note that L-glutamine’s effect on muscle mass and athletic recovery could benefit anyone losing weight in helping them prevent unwanted muscle loss while dieting. Because muscle mass is part of what dictates overall metabolism, this could help maintain a higher metabolism during the weight loss process, which can help bolster results and overall health.

4. Other medical applications 

• Inflammatory bowel disease (IBD) - L-glutamine has been seen to improve markers in intestinal permeability and reducing inflammation in patients with IBD. (4)
• Sickle cell anemia - While still in the early stages of research, L-glutamine is an approved therapy for Sickle cell anemia and worth consideration in a treatment plan. (5)

5. Immune support

The inextricable link between gut health and the immune system makes it no surprise that L-glutamine has also been shown to be very supportive in immune health. Not only has glutamine been observed as a highly used component of immune cells, it’s also been observed as a beneficial to immune function in clinical settings and studies. (6)

L-Glutamine Supplement Dosages

Depending on what you’re supplementing with L-glutamine for, and other benefits unique to your unique situation (consider: height, weight, other medications and supplements), you will be able to find the best dose with the help of your doctor.

Typically, clinical settings dose with anywhere from 5 to 60 grams of L-glutamine daily (often broken into several doses per day at those higher daily doses).

Potential Side Effects and Medication Interactions

L-glutamine is considered a very safe supplement to take. While side effects are rare and usually mild, look out for some of these common symptoms:

• Nausea
• Stomach pain
• Constipation 
• Gas
• Heartburn
• Dizziness
• Cough/hoarseness 
• Joint pain
• Mild rash
• Swelling

Medication interactions:

If you are undergoing therapies for cancer or taking anti-seizure medication, L-glutamine may not be a safe supplement. 

As always, consulting with a doctor is the only way to make sure a supplement is a safe addition to your current routine.

Should You Take L-Glutamine?

Because it is generally considered quite safe and offers such an array of important benefits to the gut, L-glutamine is something you should consider in your supplement routine. However, you’re most likely to achieve optimal health with the guidance of an expert.

If you are considering L-glutamine supplementation or struggling with some of the health concerns above, you’d likely benefit from hands-on diet and lifestyle coaching.

As one of the first functional medicine telehealth clinics in the world, we provide webcam health consultations for people around the globe.

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