The impact of dietary fibre on gastrointestinal health is well established, with copious clinical trials substantiating its many positive effects. Intriguingly, emerging research suggests that the benefits of dietary fibre extend beyond the gut, influencing liver and kidney health and function. Given the significant contribution of these organs to efficient metabolism and detoxification, this novel research is altering the landscape of clinical detoxification protocols.
Emerging research suggests that the benefits of dietary fibre extend beyond the gut, influencing liver and kidney health and function.
How does dietary fibre improve gut health?
Dietary fibre is derived from a wide variety of non-digestible carbohydrates, such as partially hydrolysed guar gum (PHGG), pectin, and β-glucans. The primary effects of dietary fibre on the gut include:
• Improved gut barrier function, primarily via increased mucins and the cells responsible for producing them, goblet cells. Mucins produce the beneficial mucous layer which not only protects the gut barrier but also supports a healthy microbiome.
• Enhanced gut barrier function as a result of short-chain fatty acid (SCFA) production via fermentation of dietary fibre. SCFAs increase the cells lining your intestines which are also responsible for nutrient absorption.
• Reduced intestinal pH by SCFAs, which alters the gut microbial profile by inhibiting the growth of pathogenic microbes and decreasing the expression of microbial virulence genes.
• Altered gut immune factors, namely increased production of immunoglobulin A (IgA) and intestinal T-cells, ultimately reducing inflammation.
Understanding the gut-liver-kidney axis
The gut supplies blood to the liver and kidneys through the portal vein, and hence it is via the positive effects that dietary fibre imparts on the gut that the liver and kidneys also benefit.
Dietary fibre has been demonstrated to increase the activity of antioxidant and detoxifying enzymes within the liver. Additionally, it can influence liver metabolism by altering bile acid pools. Bile acids are involved in the absorption of lipids and fat-soluble vitamins, and also function as signalling molecules. Dietary fibre also facilitates the production of secondary bile acids by the gut microbiota.
Dietary fibre helps to reduce the nitrogen load on the liver and kidneys by increasing microbial biomass. This facilitates the sequestration nitrogen in the gut where it acts as a food source for the microbes, thus decreasing the quantity that enters the portal circulation. Dietary fibre has been demonstrated to increase the activity of antioxidant and detoxifying enzymes within the liver
Fuel your gut with quality fibre
Increasing dietary fibre also ensures sufficient delivery of substrates, i.e. food, to the lower intestine. When this does not occur, other substrates such as amino acids are fermented in the colon, leading to the production of harmful metabolites which place stress on the kidneys.
Evidently, ensuring adequate dietary fibre intake is crucial for the maintenance of gut health and to support detoxification pathways. Daily consumption of quality fibre sources such as PHGG and fibre-rich fruits and vegetables (e.g. onions, chicory root, mushrooms, apples) gives rise to a more diverse gut microbiota, thereby promoting detoxification and improving overall health.