Protecting the Slimy Goodness in the Gut.
Just like healthy soil, health of the human gut microbiota is characterised by diversity and abundance. Also just like soil, our gut loves sunshine (exposure to sunlight/UVB light through the skin can change the human gut microbiome), it loves water, and it loves rest (there’s a reason we’re not designed to eat around the clock!).
Another principle of soil health, as passed onto me by my Dad, is to maximise the thickness and availability of groundcover (to protect the precious topsoil). The same is true for the precious and delicate epithelial barrier in the gut which requires “ground cover” in the form of intestinal mucous. Even though this article is focusing on the intestinal mucous, we of course have the ability to make mucous in our nose, mouth, sinuses, throat, lungs, reproductive tract, gall bladder, bile ducts, pancreas and liver. In fact, if human mucosal surfaces were spread out flat, they would cover an area equal to 1.5 tennis courts! Mucous is truly miracle goop when produced in healthy amounts in appropriate tissues.
Mucous is truly is the body’s unsung hero, as slimy and slippery as it is!
It sounds simple, but just like soil, it’s complex. Physically and chemically, the intestinal mucous lining an incredibly sophisticated barrier. It has a symbiotic / circular relationship with the intestinal microbiota, just as the plant life above ground has a symbiotic / circular relationship with the soil, the Earth’s biome. In fact, many of our incredible microbes live in layers of nurturing mucous!
The mucosal immune system is also the largest immune organ in the human body. In a healthy human adult, this local immune system contributes almost 80% of all immunocytes (Holmgren & Czerkinsky, 2005).
The gut mucousa has five main jobs:
To protect the mucous membranes against colonization and invasion by potentially dangerous microbes and toxins that may be encountered.
To prevent the uptake/ absorption of potentially harmful foreign substances derived from food, airborne matter and commensal microorganisms.
To prevent the development of potentially harmful immune responses to these substances if they do make it accross the gut wall.
To aid in the absorption of essential fluids and nutrients.
Serves as a ‘host prebiotic’ to stimulate the growth of beneficial microbes (such as Akkermansia muciniphila, who's optimal econiche is the mucous layer in the colon).
To do all of this, the incredibly sophisticated mucousal barrier works in synergy with the intestinal microbiota and specialised immune cells. It’s the definition of collaboration!
Now you know how important intestinal mucous is, here are some strategies to protect and promote this slimy goodness...
Fibre, fibre, fibre! Aim for 25-50g/day, from a diverse range of plants (>30-40 per week). You can learn more about fibre and access my fibre diversity challenge here.
Consider a supplemental prebiotic such as PHGG (partially hydrolysed guar gum), which has been shown to assist in mucousal lining healing, as well as serve as a gentle, prebiotic to feed a range of beneficial microbes.
Demulcents are plants which are rich in mucilage and help relieve irritation of the mucous membranes, and are sometimes referred to as mucoprotective agents. They include: Aloe vera extract/ gel, Glycyrrhiza glabra (Licorice root), Althaea officinalis (Marshmallow root), Egyptian spinach, soaked flaxseeds, soaked chia seeds, and Slippery Elm (my personal favourite!).
Avoid emulsifiers (E477, E471) where possible as they have been shown to induce microbiota alterations associated with mucousal impairment and cause mucousal erosion.
Given that the intestinal mucous is made up mostly of water (90-95%), stay hydrated.
Consider a probiotic containing Lactobacillus reuteri and Bifidobacterium longum, as these have been shown to stimulate mucous production and restore mucousal thickness (Paone & Cani, 2020).
Increase your intake of dietary polyphenols (berries, brightly coloured fruit, olives, herbs, spices, cocoa, coffee, vegetables, tea). Polyphenols have also been shown to increase levels of Akkermansia mucinophilia, promoting the healthy mucin production (Anhe et al, 2016). Seaweed and prickly pear have also been shown to be beneficial for the gastrointestinal mucous lining (Bacchus, 2021).
As far as isolated nutrients go, Vitamin A is my all time favourite! Vitamin A promotes mucin secretion and increases the integrity of intestinal mucus (Huang et al, 2018).
As always, please seek professional guidance before starting any supplements to make sure you’re taking the right doses and formulations for you.
