Gut Health

L-Glutamine for Leaky Gut: The 5 Big Mistakes Most People Make (2022 Update)

For those people with leaky gut syndrome, finding a good treatment plan can lead to both natural and prescription remedies. So, can L-Glutamine help treat leaky gut syndrome in 2022? If you take it correctly, the answer is yes. This supplement can potentially help with your leaky gut syndrome. We're going to go over what leaky gut syndrome and L-Glutamine are, as well as how it can heal your leaky gut. We'll also talk about the top five big mistakes people make when they take L-Glutamine for their leaky gut syndrome so you can avoid them. Finally, we'll go over the correct dosage. Our goal is to give you all of the information and tools you need to decide if L-Glutamine is the correct supplement for your lifestyle and situation.


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What is Leaky Gut Syndrome

What is L-Glutamine

Why Does L-Glutamine Heal Leaky Gut

5 Mistakes When Taking L-Glutamine for Leaky Gut

  1. Not Taking the Correct Dose of L-Glutamine
  2. Taking L-Glutamine with Food
  3. Taking L-Glutamine with a Hot Drink or Beverage
  4. Believing That Getting L-Glutamine from Food Sources Is Sufficient
  5. Taking L-Glutamine in Pill Form Instead of Powder Form
Final Thoughts on Taking L-Glutamine for Leaky Gut

What Is Leaky Gut Syndrome?

Leaky gut syndrome, or increased intestinal permeability, is a relatively new diagnosis in the medical world. It used to be a blanket term that encompassed a wide variety of gastrointestinal issues, but medical professionals have slowly narrowed it down to one condition. Your stomach and intestines have a durable inner lining that has a thick layer of mucus to protect it from the acid in your stomach and the bacteria in your body. In a healthy GI tract, this internal lining is a tight layer of cells and tissue with no obvious cracks or fissures. However, when you have leaky gut syndrome, you develop cracks or fissures in this inner lining. These spaces allow bacteria and foreign particles to slip through into your body. When this happens, you can experience system-wide inflammation. In addition to this inflammation, you may experience abdominal pain, loss of appetite, fatigue, fever, and abdominal cramping.

What Is L-Glutamine?

L-Glutamine is one of 20 amino acids in your body, and it's known as a conditionally essential amino acid for the roles it plays in your body (1). Amino acids are commonly known as the building blocks for your bodily functions and healthy growth. Out of the 20 amino acids present in your body, L-Glutamine is the most prevalent one. This is what makes it a conditionally essential amino acid. You can find two different types of L-Glutamine in your body (2). The type of L-Glutamine that you get in a supplement form and take with food is free-form L-Glutamine. Taking this type of L-Glutamine with food helps your body absorb higher amounts of it each time you take it. The second type of L-Glutamine is Trans-Alanyl-Glutamine (TAG). Trans-Alanyl-Glutamine forms when two amino acids join together. You can take it by itself, and your body can absorb it without food.

Why Does L-Glutamine Heal Leaky Gut?

L-Glutamine is a natural and powerful supplement that can help heal leaky gut. First, L-Glutamine has powerful anti-inflammatory properties (3). One study took 20 participants with leaky gut syndrome and split them into two equal groups. During the course of the study, Group B got a daily L-Glutamine supplement and the control group got a placebo (4). They found that the inflammation levels for Group B were significantly lower than the control group at the end of the study. L-Glutamine also works on a cellular level to repair the cracks or fissures that leaky gut syndrome comes with (5). Researchers studied L-Glutamine's healing properties by taking 105 mice with intestinal permeability and dividing them into two groups. Both groups got the same standard diet over the course of the test, but one group also got an L-Glutamine supplement each day. They followed these mice over five months and tested their intestinal permeability at the end of the trial (6). The group who got the L-Glutamine supplement showed decreased intestinal permeability over the control group.

A 2022 literature review on the effects of L-glutamine on leaky gut analyses all the relevant studies in the area. (7) One of them was a randomised placebo-controlled trial carried out on 54 patients who suffered from IBS in a controlled group. It proved that glutamine supplementation can decrease intestinal hyperpermeability in humans after 8 weeks. (8)

Plus, several people who suffer from leaky gut have tried our Ultra Absorb™ L-Glutamine and their testimonials are conclusive:

Fixed my leaky gut!

I tried so many things to fix my leaky gut and I wish I had found this product earlier! I take one small scoop in the morning and one scoop of the collagen protein in a smoothie and it seems to have helped me get on top of my gut issues. Thank you!

Charlene E.

5 Mistakes People Make When Taking L-Glutamine for Leaky Gut Syndrome

Now that you know how L-Glutamine can help heal your leaky gut syndrome and what it is, we'll go over the top five mistakes people make when it comes to actually taking this supplement. This way, you'll know what to avoid doing if you decide to take it. This means that you can start feeling the benefits quicker than people who make these five common mistakes.

1. Not Taking the Correct Dose of L-Glutamine

One of the main issues with taking L-Glutamine is the conflicting dosage information that is available to you. If you purchase an L-Glutamine supplement, you'll most likely notice that the recommended dosage ranges between one or two grams per day. Most people take this because it's what the label recommends. However, this may not be a high enough dosage to enable you to get the full benefits.

Several studies showed that you may need to take higher amounts of L-Glutamine to help improve your gut health. These dosage amounts are much higher than current supplements recommend, and this is where confusion starts to set in. One study showed that children had decreased intestinal permeability when they took 24g of L-Glutamine every day (9). This is over 10 times the recommended dosage. The other group got 15g of a placebo every day for 10 days. At the end of the study, the group who got the higher concentrations of L-Glutamine saw significant improvement in their gut health. Another study with 20 patients who underwent abdominal surgery showed that taking high amounts of L-Glutamine can improve their gut health. In this double-blind study, participants were split into two groups and given 30g of L-Glutamine and a placebo (10). After seven days, researchers found reduced inflammation levels and a more well-maintained intestinal barrier in the patients who got the L-Glutamine supplement.

What does this mean for you? One final study showed that a good formula that helps ensure you get enough L-Glutamine each day is 0.5g of L-Glutamine per kg of body weight (11). For example, for someone who weighs 60kg, the formula would be:

    (60kg body weight) x (0.5g L-Glutamine) = 30g of L-Glutamine per day

      You may want to start with a lower dose and slowly work your way up to a larger dose to make sure that your body tolerates the supplement well.

      scoop of L-glutamine for leaky gut

      2. Taking L-Glutamine With Food

      While you should take free-form L-Glutamine with food, you shouldn't take Trans-Alanyl-Glutamine with food. A lot of people believe that this form of L-Glutamine absorbs into your body better when you have food act as a buffer between your body and the amino acid. However, this isn't true, and it can actually decrease how much L-Glutamine manages to absorb into your body (12).

      The foods you eat contain amino acids, and this is especially true for foods with high protein content. If you add this influx of amino acids to L-Glutamine, the amino acids will compete to absorb into your body. This means that you may not get as much L-Glutamine into your system as you want, even by taking the higher dosages of it.

      One study took patients who decided to undergo elective surgery to repair traumatic injuries and split them into two separate groups (13). Group A got L-Glutamine supplements with food and Group B got L-Glutamine supplements on an empty stomach. They monitored the results after the surgical procedure and found that Group B showed reduced surgical site inflammation. This led them to believe that there were higher levels of L-Glutamine in their bodies than in Group A's bodies.

      A second study took two groups of participants and split them into two groups (14). One group took their L-Glutamine supplement each day with a light meal, and the second group took their L-Glutamine supplement on an empty stomach for a week. At the end of the study, researchers found that the group who took the L-Glutamine on an empty stomach had higher levels of nutrient absorption than the group who ate a light meal with their L-Glutamine supplement.

      3. Taking L-Glutamine with a Hot Drink or Beverage

      Many people believe that they can take their L-Glutamine supplement with hot or cold beverages. However, if you routinely take your supplement mixed into a hot beverage, you may not see the results you desire because this can actually work against L-Glutamine's effectiveness. Heat can destroy parts of the amino acids, and it can also decrease the amino acid's viability (15). This can reduce the overall absorption rate.

      A study heated soybeans up to 126 degrees Fahrenheit and analysed the effect of the heat on the amino acids present in the beans, including L-Glutamine (16). They found that prolonged exposure to the heat altered the amino acids, and key parts of the amino acids were destroyed completely. This reduces the effectiveness of the L-Glutamine because it won't be able to absorb into your body as well as it could if it was whole.

      The hotter the drink or beverage is and the longer the L-Glutamine sits in the heat, the less effective it's going to be when you digest it. This means that you want to store your L-Glutamine in a cool and dry place. It should be somewhere where it won't experience large temperature fluctuations like in a cupboard or pantry.

      You also want to take your L-Glutamine supplement with water or other cool beverages. If you do this, you'll be able to get the most out of your L-Glutamine supplement as long as you take it on a routine basis. Don't mix it with lukewarm drinks either. Stick to cold drinks and beverages. 

      Though a 2022 study proved that accompanying L-glutamine with foods that contain trelahose, such as honey, shrimp and yeast, can make this amino acid less sensitive to temperature changes (17), we still recommend drinking it only with water so that your gut can absorb as much L-glutamine as possible.

      4. Believing That Getting L-Glutamine from Food Sources Is Sufficient

      Healthy people with no gastrointestinal issues may be able to get away with getting their daily dose of L-Glutamine from protein shakes and food. However, people with stomach issues like leaky gut syndrome need significantly higher amounts each day to heal and maintain their GI tract health.

      Additionally, this L-Glutamine has to be in a more pure form so it can keep up with the present digestive tract issues. One thing you have to keep in mind is that when you get L-Glutamine from food, it competes with the other amino acids in the food you eat. This can reduce the amount of L-Glutamine that manages to get into your system, even if you eat foods rich in it. For example (18):

      • Eggs: 4.4% L-Glutamine (0.6g per 100g of eggs)
      • Beef: 4.8% L-Glutamine (1.2g per 100g of beef)
      • Skim Milk: 8.1% L-Glutamine (0.3g per 100g of milk)
      • Tofu: 9.1% L-Glutamine (0.6g per 100g of tofu)

      These percentages may seem like a lot, but only a fraction will make it into your system. One study showed that people with gastrointestinal issues and athletes need more L-Glutamine on a daily basis to maintain their health (19). This is because athletes burn through high levels of L-Glutamine when they work out and compete, and people with gastrointestinal issues need higher levels to heal.

      Another study showed that people with weakened immune systems need higher daily levels of L-Glutamine than they can get from food alone (20). The study divided participants into groups and gave one group a higher dose of L-Glutamine, the second group a lower dose, and the last group a placebo. At the end of the study, they found that the group who got the higher dose of L-Glutamine did better and had reduced inflammation than the group who got the placebo and lower dose of L-Glutamine.

      5. Taking L-Glutamine in Pill Form Instead of Powder Form

      We know that most L-Glutamine supplements in capsule form come in one or two grams as the standard dose. If you need to take 20 or 30 grams of L-Glutamine per day, it doesn't make sense to try and swallow 10 to 15 supplement pills when you can take it in one or two doses with a powder.

      Also, did you know that taking a large amount of capsules each day can be bad for your health? (21) Consuming large amounts of gelatin-based capsules each day can put a strain on your liver and kidneys. They're also more difficult for your body to break down and digest than traditional powder supplements are. This is even more critical if you already have digestive problems like leaky gut syndrome.

      One study showed that taking L-Glutamine powder had a better absorption rate than taking multiple capsules each day (22). Eight participants got L-Glutamine supplements over the course of several hours. They measured the L-Glutamine levels in the blood at the end of the study and found that the participants who got the powder form had higher levels present. The Consumer Research Lab found that some capsules don't disintegrate properly, and this interferes with the absorption rate of the supplement in said capsules (23). With a powder, you don't have to worry about this because you dissolve it in water or your favourite cool drink before taking it. There is no capsule to worry about, and it can absorb straight into your body.

      What Is the Correct Dose of L-Glutamine to Help Heal Leaky Gut Syndrome?

      As we mentioned earlier, most people take one or two grams of L-Glutamine each day because this is the amount that the supplement packaging recommends. This amount is fine for people who don't have problems with their digestive systems, but it simply isn't enough for people with leaky gut syndrome. You have to understand that most L-Glutamine supplements target athletes or weightlifters whose main focus is helping their bodies recover and their muscles recover after competition or training (24). Two milligrams is enough to help them through this process, and they're generally in very good shape to begin with.

      People with digestive issues like leaky gut syndrome need higher amounts of L-Glutamine to be able to repair any existing damage and keep their GI tract lining in good shape (25). You can take 0.5g of L-Glutamine per kg of body weight, or you can start an L-Glutamine maintenance protocol. This protocol goes by weight, and you want to ensure that you're getting enough L-Glutamine to support your gut health. You may want to start off slowly and increase the dose over several days to ensure that your body responds well to the supplement. Also, it's a good idea to talk to your doctor before you start taking any new supplements, so you're sure that it's a good choice for you. The Food and Drug Administration developed the following L-Glutamine Maintenance Protocol (26): l-glutamine for leaky gut You can also try the L-Glutamine Taper and Maintenance Protocol if you're more comfortable with introducing this supplement to your diet on a small dose and rapidly increasing the dosage to jump-start your gut's healing process. This protocol will load L-Glutamine into your diet and slowly taper you back off. After the initial two weeks, you can take 5g to 10g each day for maintenance depending on how you feel. l-glutamine for leaky gut

      Final Thoughts on Taking L-Glutamine for Leaky Gut

      Once you get through one cycle of the protocols, you can see how you feel and continue or discontinue the protocols as you see fit. L-Glutamine supplements have a broad range of health benefits if you take them correctly. Maybe you should talk to your doctor and see if you can benefit from an L-Glutamine supplement. 

      Editor's note: Originally posted on August 27, 2018. Edited and updated for comprehensiveness on July 5th, 2022.


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