Is glutamine really all that’s required to heal a leaky gut? Or is it just another health fad?
If you google leaky gut + glutamine, you’ll be flooded with more than ten pages of articles. The majority of these articles praise glutamine as being a cure-all for leaky gut syndrome (aka intestinal permeability).
As with most fads, they start out in the realm of science. From there, they quickly blow up into being much bigger than what was originally published in the research. It’s a bit like that game of telephone we all played in our youth. The message at the end is often much different than the beginning.
So is glutamine a legitimate help to those with leaky gut?
Or is it another over-hyped natural health product?
What is leaky gut (aka, intestinal permeability)?
The gastrointestinal (GI) tract runs from the bottom of the throat (esophagus) all the way to the anus. This entire tract has a single contiguous layer of cells that separates the inside of the tract from the external environment. Ideally, only small, specific nutrients make it from the digestive tract into our body. In a leaky gut, our body’s ability to filter the good nutrients from the bad becomes challenged.
Separation between the inside and outside of the GI tract is of paramount importance. There are a wide variety of environmental agents that can create or perpetuate inflammation if they get through the intestinal barrier. As I’ve written about before, you know that leaky gut is a prerequisite to developing an autoimmune disease.
In a leaky gut, our body’s ability to filter the good from the bad becomes challenged. Imagine your digestive tract to be like cheese cloth. Small nutrients can make it through the cheese cloth and into our body. There, our body uses these nutrients for different cellular functions. When we have leaky gut, our cheese cloth has large holes in it. These large holes allow items that would normally remain in the digestive tract to enter our body’s internal environment. This is where problems can begin.
What causes leaky gut? (1)
Leaky gut is a lifestyle disease – it occurs because of factors under our control. More specifically, the food we eat, the stresses of our daily life, and the bacteria we were exposed to early in life play a substantial role in developing leaky gut.
In your large intestine, the number of bacteria you have can reach levels of up to one trillion per gram. Of these trillions of bacteria, most of us have about one hundred different varieties inhabiting our digestive tract. Proper functioning of these diverse bacterial colonies is integral to gastrointestinal health.
In general, leaky gut can be caused by:
- Diets high in processed fats and carbohydrates (ie. fast food and junk food) increases intestinal permeability.
- Dietary sugars (specifically fructose) can create an overgrowth of bad bacteria. The overgrowth of bad bacteria will then lead to leaky gut. Read more about how bad bacteria can lead to IBS.
- Foods high in quercetin (grapes, onions) increase the ability for cells in our digestive tract to better handle challenges. Unfortunately, many of these foods are missing from the standard Western diet.
- Vitamin A
- Has been shown to regulate the growth and differentiation of our intestinal cells.
- Vitamin A deficiency results in an increased susceptibility to infection. Within a few weeks of being deficient in vitamin A, our intestinal barrier becomes impaired.
- Vitamin D
- Vitamin D deficiency has been correlated with an increased severity of symptoms commonly found in IBS.
- Recent research suggests that a lack of vitamin D may compromise the mucosal barrier in our digestive tract – thus contributing to leaky gut.
Short-chain fatty acid deficiency
- When the bacteria in your digestive tract ferment carbohydrates they produce short-chain fatty acids.
- When we don’t eat enough fiber we can have a deficiency in short-chain fatty acids. There are two types of fiber: soluble and insoluble.
- Soluble fiber absorbs water and turns into a gel-like mush. Oatmeal is the perfect example of soluble fiber.
- Insoluble fiber is the ideal food for the bacteria in our digestive tract.
- This type of fiber doesn’t change when you add water to it. The roughage that occurs when you eat celery is an example of insoluble fiber as it does not change when water is added to it.
- A deficiency in the short-chain fatty acid butyrate has been shown to cause lesions in the digestive tract – thus contributing to leaky gut.
- In rat models, a butyrate supplementation helped to maintain the integrity of the gut barrier.
Lack of prebiotics in the diet
- Prebiotics are the building blocks your intestinal bacteria needs to create short-chain fatty acids. They are a non-digestible fiber found in a number of different vegetables.
- Prebiotics help to regulate the amount and type of beneficial bacteria in your intestine. In turn, this can improve the integrity of your digestive tract.
- By feeding the healthy bacteria, prebiotics also protect against bacterial infections such as salmonella.
Deficiency of probiotics in the GI tract
- Commensal or beneficial bacteria are known to be necessary for a healthy digestive tract.
- A lack of beneficial bacteria increases the risk for bad (pathogenic) bacteria to take up residence in your digestive tract. An overgrowth of pathogenic bacteria will lead to a leaky gut.
How is leaky gut diagnosed?
Permeability tests use specific carbohydrates called oligosaccharides and sugars. Oligosaccharides are very large molecules and will only cross the intestinal barrier if leaky gut exists. Comparatively, sugars molecules are small and therefore thought to easily cross the intestinal barrier.
To perform the test, one drinks a solution of oligosaccharides and sugars. The small sugar molecules are thought to cross the intestinal barrier, entering the urine. The large oligosaccharides molecules will cross the barrier only if leaky gut exists and eventually end up in the urine after being filtered by the kidneys.
Measuring these molecules in the urine can be used to determine if leaky gut is present.
Increased permeability for saccharides has been reported in patients with celiac disease, adverse reaction to food, and in critically ill patients or patients undergoing major surgery.
How to treat a leaky gut
As discussed at the beginning of this post, L-glutamine is the current all-star supplement for treating leaky gut. L-glutamine is an amino acid that repairs the gut’s mucosal lining and reduces intestinal inflammation. However, though glutamine has been shown to be effective at assisting with repairing leaky gut, it is often not enough and may only be a band-aid fix.
More important than treatment is ensuring leaky gut does not develop at all. In order to avoid leaky gut in the first place, all potential food allergies/sensitivities must be identified. This can be done through an IgG blood test or by following an elimination diet. Check out this post for more information on how to properly implement an elimination diet.
If you have been diagnosed with leaky gut, don’t immediately reach for the glutamine. Instead, take the time to identify the underlying causes I outlined above.
Once the root cause of leaky gut has been removed, your focus can then be turned towards a targeted supplementation protocol to help rebuild the integrity of the intestinal lining.
At Flourish Clinic, we recommend the following protocol to heal a leaky gut:
- Vitamin A and Vitamin D – ideally both of these should be sourced from a high-quality cod liver oil.
- Zinc – A very high dose is required. Do not supplement high levels of zinc greater than eight weeks.
- Butyrate or short-chain fatty acids
- Sodium butyrate can be supplemented at 3-4g/day
- Short chain fatty acids should be obtained by consuming at least one serving per day of insoluble fibre or prebiotics.
- Foods like green plantain, Jerusalem artichoke, chicory root, and yucca (cassava) are the best sources of insoluble fiber and prebiotics.
- Take a probiotic supplement on a regular basis. Research has shown certain strains of probiotics have greater effects than others. Avoid generic strains of probiotics. The following types of probiotics have been proven to work:
- Lactobacisllus Plantarum
- Sacaromyces boulardi
- Soil based organisms
- E coli nissel 1917
- Glutamine or whey protein (if tolerated)
- 20-40g of glutamine/day
- For those with known dairy sensitivities, whey protein may not be the best option.
- This is a prescription medication used to treat constipation in IBS.
- It has also been shown to assist with treatment of leaky gut.
While glutamine is indeed an effective means of treating leaky gut, glutamine alone is likely not a cure. Instead, focus should be on removing offending foods from the diet. If glutamine is to be supplemented, it is best to combine it with the above supplements/medications for a more effective treatment.
Now, I want to hear from you.
How have you treated leaky gut?
Also published on Medium.