L Glutamine Weight Loss: Does L Glutamine Help?

Written by Ben Carlisle

Last updated on: Sep 18, 2022

Kimura Athletic may earn a small commission through our links. Learn more.

We’re all earnestly trying to find the magic recipe to help us shed a few extra holiday pounds, but with all the fad diets, we are left if a whirlwind of endless options that never seem to do the trick. Well, your hunt for the perfect weight loss supplement may be over today! Your golden ticket lies within the amino acid l-glutamine.

image 1

L-glutamine aids in weight loss by enhancing your glucose metabolism by altering your gut microbes. An improved ratio between the beneficial and harmful bacteria reduces obesity biomarkers, protects your body against inflammation and a leaky gut, and improves blood sugar control.

If you’re interested in jumping on the healthy weight loss wagon, continue reading to see how l-glutamine your ticket on the safe and effective ride to a thinner life.

Does L Glutamine Help You Lose Weight?

Most straightforwardly, l-glutamine can help you keep the additional weight off by enhancing your glucose metabolism, minimising your food cravings, and supplying your body with more energy.

An overweight person’s body requires more l-glutamine than usual; if your body lacks sufficient amounts of this amino acid, your body will start to break down its muscle tissue to access extra l-glutamine. In turn, you begin to lose muscle mass.

With sufficient l-glutamine in your system, your body can lose weight better. More so, adding l-glutamine to your diet or consuming it through supplements will help reduce those horrid yet irresistible cravings for high-glycemic carbs.

We’ll dive into the details after providing a better explanation of what l-glutamine is for those who do not know.

Better Understanding L-Glutamine?

Glutamine is the most bountiful amino acid in your body; this versatile amino acid plays a pivotal role in improving the immune system, gut function, and intestinal health (1). However, glutamine’s primary purpose is to serve as the building block for protein.

Glutamine exists in two different forms:

• L-glutamine

• D-glutamine

While almost identical, these two forms contain slightly different molecular arrangements (2). However, while l-glutamine makes proteins and performs various other functions, d-glutamine shows to be relatively unimportant for living organisms (3).

So, in this article, we’ll focus on l-glutamine.

Your body can naturally self-produce l-glutamine in your body. It is the amplest free amino acid in your blood (4). However, at times, your body may require higher consistencies than what it can produce (especially during stress), making it “conditionally essential” in times of stress or illness (5).

When our bodies cease producing adequate amounts of l-glutamine, we can, fortunately, consider drinking a supplement to boost the production of this conditionally essential amino acid.

Now that we have a clearer idea of what l-glutamine is, we can dive into the good stuff - how it supports weight loss.

How Does L-Glutamine Support Weight Loss?

Research suggests that l-glutamine can support weight loss through various mechanisms.

• Enhancing glucose metabolism

• Altering your gut microbes

• Protecting your body against inflammation and a leaky gut

• Improving blood sugar control

However, note that findings suggest that l-glutamine supplements do not significantly affect body composition and muscle performance during resistance training in healthy young adults (6).

L-Glutamine Enhances Glucose Metabolism

Several findings show that l-glutamine is a safe and effective supplement for consumption; it favours weight loss and shows that it can enhance glucose metabolism (7).

A pilot study was conducted to identify whether chronic oral glutamine supplements can alter the metabolic parameters in overweight and obese individuals and modulate the molecular pathways in the vital tissues linked to insulin in rats.

None of the patients altered their lifestyle or dietary habits; however, there was a significant decline in their waist circumference and body weight after consuming the supplement (7).

The pilot study proves that glutamine plays a role in glucose metabolism by demonstrating that glutamine supplementation can decrease up to 50% of exogenous insulin (the insulin people inject or infuse), reaching the same glycemic levels as non-supplemented patients (7).

So, glutamine supplementation seems to improve insulin sensitivity when the glutamine stores are depleted, decreasing the need for exogenous insulin. More so, glutamine supplementation prevents the development of diabetes and obesity in rats fed high-fat diets (7).

Therefore, we conclude that glutamine supplements may improve glucose metabolism and favour weight loss, independently of calorie restriction.

L-Glutamine Alters Gut Microbes

Your gut microbiome (the microorganisms living in your intestines) plays a pivotal role in numerous aspects of health, including managing weight. In addition, the gut microbiota influences the energy utilisation from your diet and the genes that regulate energy storage and expenditure (8).

Evidence shows that obese subjects have lower fecal glutamine ratios than non-obese individuals (9). Moreover, the gut microbiota composition in obese individuals differs from lean individuals, reporting that overweight people typically contain fewer Bacteroidetes (good bacteria) (10).

Studies indicate that consuming l-glutamine supplements can alter the composition of your gut microbes - essentially, they are the colony of beneficial bacteria in your digestive tract (11).

A higher ratio of Firmicutes (the bad guys) to Bacteroidetes (the good guys) is a biomarker for obesity. Consuming oral l-glutamine supplementation for a short period changed the gut microbiota composition in overweight and obese individuals by reducing the Firmicutes to Bacteroidetes ratio (12).

L-Glutamine Protects The Body Against Inflammation

Consuming l-glutamine supplements may help protect your body against chronic inflammation, linked to obesity among other chronic conditions (713).

Despite access to healthy, nutrient-rich foods, most individuals in the U.S. exert poor lifestyle and diet choices that exhibit adverse side effects on their overall health and gut. In addition, processed foods typically increase gut and systemic inflammation, damaging the intestines and increasing gut permeability (14).

Research shows that glutamine is a promising supplement for mitigating gut inflammation and damage (15). If you have a leaky gut, your intestines contain small holes that allow bacteria to seep through, causing your body to send an inflammatory response to stop the infection.

The l-glutamine forms a thin barrier between the intestinal wall and bacteria growing in your digestive tract, allowing the fissures and holes to heal. In turn, the inflammation starts to decrease (16).

L-Glutamine Improves Blood Sugar Control

Finally, studies show that l-glutamine improves blood sugar control and enhances your cells’ insulin sensitivity. In turn, it improves your body’s ability to use endogenous insulin (the insulin that your pancreas produces) efficiently (17).

Improved blood sugar control and insulin use can aid in weight loss as impaired insulin sensitivity links to a greater risk of obesity (18). L-glutamine reduces the level of insulin in your blood, reducing body fat and blood pressure and encouraging a smaller waistline (19).

How To Use L-Glutamine Supplements?

L-glutamine is naturally present in everyday foods like tofu, eggs, beef, or supplements, including capsules or powders.

Consuming this amino acid is generally safe for short-term use when you follow the recommended guidelines; no adverse side effects have been seen (20). Most doses range anything between 500mg to 3g should be consumed daily between meals.

According to a risk assessment consuming 14g of l-glutamine supplements a day is harmless (20). However, studies show that doses of 30g per day aid in weight loss (21).

While short-term use is safe, more research needs to be done to evaluate the possible side effects of supplementing l-glutamine long-term efficiently. Additionally, always talk to your healthcare practitioner before including any new supplements in your routine.


Losing weight can be quite a struggle, especially if you lack the tools to help you accomplish your goal. These four reasons help us understand why l-glutamine is an excellent option to encourage short-term weight loss without drastic lifestyle changes.

If your healthcare practitioner gives you the go-ahead, you may want to give it a try. However, note that you should not see l-glutamine as a quick fix; instead, pair the supplement with a healthy diet and exercise.

Related Articles


1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6266414/

2. https://pubmed.ncbi.nlm.nih.gov/18642934/

3. https://pubmed.ncbi.nlm.nih.gov/12579515/

4. https://pubmed.ncbi.nlm.nih.gov/8665180/

5. https://medlineplus.gov/ency/article/002222.htm

6. https://pubmed.ncbi.nlm.nih.gov/11822473/

7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6471297/

8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5082693/

9. https://pubmed.ncbi.nlm.nih.gov/30888539/

10. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5960470/

11. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6834172/

12. https://pubmed.ncbi.nlm.nih.gov/25933498/

13. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5507106/

14. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3232439/

15. https://www.sciencedirect.com/science/article/pii/S2213453021000112

16. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4369670/

17. https://www.researchgate.net/publication/285772772_Metabolic_effects_of_glutamine_on_insulin_sensitivity

18. https://pubmed.ncbi.nlm.nih.gov/29397563/

19. https://pubmed.ncbi.nlm.nih.gov/25466655/

20. https://pubmed.ncbi.nlm.nih.gov/18325648/

21. https://academic.oup.com/jn/article/138/10/2045S/4670120

View More Articles