Diets with a lower protein-to-fibre ratio may promote a healthier and more diverse gut microbiome, a study has found, suggesting eating more plant-based proteins – as opposed to animal-based ones – might be better for gut health.
The study suggests that including more plant-based proteins in the diet, as opposed to animal-based ones, might help promote a healthier balance of gut microbes, and result in a microbiome with more fibre-fermenting microbes, and less protein-fermenting microbes.
Diversity of gut microbes is generally considered beneficial for overall gut health as it indicates a more resilient and adaptable microbiome. A diet high in animal protein may lead to a less diverse and potentially less healthy gut microbiome. Conversely, diets rich in plant proteins are broadly considered advantageous for gut health as they promote the growth of beneficial bacteria.
Robert Dixon, science and technology manager for the gut microbiome at Unilever, shared the study on a LinkedIn post, saying: “Cool study and another piece of evidence supporting that diverse plant based diets are the best way of improving your gut microbiome.”
The study, published in the European Journal of Nutrition, investigated the impact of dietary protein to fibre ratio on gut microbiome composition and functionality. Two cohorts were included: healthy Italian and Dutch individuals on an omnivore diet. Subjects’ diets were recorded through Food Frequency Questionnaires and analysed for nutrient composition, and their gut microbiome was assessed through faecal samples.
The team found that the ratio of dietary protein-to-fibre significantly influenced the type and quantity of microbes in the gut. Individuals who consumed higher amounts of animal protein, as opposed to plant protein, tended to harbor different types of gut microbes than those who consumed more plant protein. Individuals with a higher ratio of protein-to-fibre in their diet tended to have more microbes that specialised in breaking down protein. On the other hand, those with a higher ratio-of-fibre to protein had more microbes dedicated to breaking down fibre.
Proteolytic microbes – microbes that break down protein – were found at higher levels in individuals consuming more protein than fibre ratio and animal proteins. A proteolytic gut microbiome may be detrimental to health and contribute to the production of toxic metabolites and pro-inflammatory microorganisms. Individuals whose diets had a lower protein to fibre ratio, had an increase in the diversity of genes within the gut microbes.
According to the team, further research is needed to confirm whether and to what extent the ratio of protein to fibre may affect gut microbiome composition and health outcomes.
Understanding this relationship could create opportunities for personalised nutrition plans that optimise gut health. The researchers used the example of an intervention that adjusted the protein-to-fibre ratio in the diet to promote a healthier balance of gut microbes, which they said could potentially improve gut microbiome composition and individual health and wellbeing.
