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Leaky gut – The hype about hyperpermeability

Leaky gut – The hype about hyperpermeability
By Ellie Isom 6 days ago 8064 Views

You may have heard the term ‘Leaky gut’ being batted around, but what does it actually mean? Is it really a thing?

Yes – it is a thing! Leaky gut is the colloquial term used to describe the increased permeability of the gut wall, or ‘intestinal hyperpermeability'.

One of the most important functions of our gut is its essential role as a barrier to the environment. This structural barrier encompasses an epithelial layer, and a mucus layer which our intestinal microflora adhere to. The top layer (the epithelium) contains tight junctions, which regulate the movement of water and other small molecules in and out of our digestive tract, opening and closing when required. 1 However, certain factors can also unfavourably open, and disrupt these tight junctions, such as infections and inflammation, as well as foods, such as those containing gluten.

How do you know if you have leaky gut? Without testing (a holistic doctor or a nutritional therapist can recommend the right test), it is difficult to know for sure, but there are certain symptoms and conditions that are associated with it. Because the functioning of this barrier is vast, and involves regulating our metabolism, immunity, digestion, absorption, nervous and endocrine function,2 disturbance to this barrier has been linked to many health conditions, such as allergies3, autism and autoimmunity4 (e.g. coeliac disease), to name a few. You may also suffer with diarrhoea or constipation, frequent headaches, food intolerances, skin rashes or other skin-related problems, recurrent infections or problems with memory and concentration.

Even if you are not sure if you have it or not, supporting a healthy gut lining and preventing leaky gut can only benefit your health! So what can you do?

Start with your diet

The food we consume comes into direct contact with the cells lining our digestive tract, therefore, quality is everything. For a sensitive or inflamed digestive tract, certain foods can be further irritating, such as dairy and chilli. In these circumstances, focusing on easily digestible, soothing foods, like soups, bone broths, and smoothies, can be beneficial.

Is gluten an issue?

As mentioned previously, gluten containing foods can contribute to intestinal hyperpermeability. Zonulin is a protein that acts as a gatekeeper of tight junctions in the small intestine, increasing permeability.5 Its secretion is heightened by the presence of gluten.6 Therefore, the first point of call for addressing a leaky gut could be adopting a gluten free diet, directly excluding this stimulant.

However, it’s not just gluten that can have that effect. Lectins - the proteins found in a wide range of legumes and vegetables, especially if not cooked or prepared properly, can bind to the surface of cells lining the intestine, and inhibit intestinal cell repair, potentially keeping tight junctions open.7

Include gut-healing nutrients in your daily regime

If the lining of the digestive tract is damaged, the body will require an increased supply of nutrients that aid repair, as well as the building blocks for connective tissue. There are many that we could include, but the following are our favourites:

* Glutamine – the most abundant non-essential amino acid in human muscle. Glutamine supplementation can protect against inflammation, improve intestinal barrier function and help to reduce intestinal permeability.8,9,10

* Collagen – The gut wall contains collagen fibres that strengthen the whole structure. Currently, there appears to be a research gap in relation to collagen supplementation and leaky gut, but some preliminary studies are beginning to highlight the use of type 1 collagen for intestinal cell maintenance.11

* Nucleotides – these organic compounds form the building blocks of DNA, which is essential for cell division and repair.12 Dietary sources of nucleotides include organ meats and seafood.

* Zinc – encourages healing,13 and reduces gut inflammation.14,15 Zinc has also been shown to reduce gut permeability via actively having a positive effect on tight junctions.16,17

* N-Acetyl Glucosamine (N.A.G) – an essential components of all body tissues, including the digestive tract lining. It promotes growth and intestinal repair.18 N.A.G. can also bind to lectins, rendering them inactive, and therefore unable to bind to cell surface membranes.19

* Antioxidants – such as vitamin C, can increase collagen synthesis.20,21 Antioxidant therapy has also been proposed as beneficial for digestive conditions such as IBD via mopping up free radicals, which can be produced via gut bacteria, as well as via reducing inflammation.22

* Probiotics – our gut bacteria attach to the mucus layer of the intestinal barrier, working to support gut integrity.23,24 In fact, alterations to our gut microflora can actually cause leaky gut. Therefore, probiotic supplementation or increasing the intake of probiotic foods can be beneficial and has been linked to a reduction in intestinal inflammation and permeability risk, especially during endurance training.25

Is your lifestyle the problem?

Diet and supplementation are important, but if your lifestyle is at the core of your digestive issues, it is key to sort out some of those underlying drivers to achieve better results in the long run. Many lifestyle factors can further increase gut permeability. These include medications, such as NSAIDS (e.g. ibuprofen) and aspirin, alcohol and stress.26,27,28 In addition, strenuous exercise is also associated with the damaging of the gut wall, increasing permeability.29 Therefore, incorporating particular activities into daily life, such as rest days between intensive exercise sessions and meditation to help with stress management, could be incredibly useful.

These are just a few of the key steps that can be considered when trying to tackle intestinal hyperpermeability. Our gut health is so important and linked to many other body systems, therefore keeping it healthy and functioning properly is integral for ensuring and maintaining our overall health.

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20 Murad et al Proc.Natl.Acad.Sci.USA 78(5)

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