From microbiota to menu: predicting individual responses to dietary components

Abstract

Over the past few decades, the prevalence of chronic inflammatory and metabolic diseases has risen sharply, coinciding with significant environmental and lifestyle changes. While genetics play a role, the rapid increase suggests that non-genetic factors are key contributors. Among these, the gut microbiota—a vast community of microorganisms residing in the intestines—has emerged as a central regulator of health. A growing body of evidence links microbial imbalances, or dysbiosis, to various diseases, with reduced microbial richness and diversity observed in industrialised populations compared with those in non-industrialised settings. Many beneficial microbial species, once prevalent in the human gut, are now disappearing, likely due to changes in diet, hygiene and antibiotic use. One of the most influential factors shaping the gut microbiota is diet. The Westernised diet, characterised by high consumption of processed foods and food additives, has been associated with microbiota alterations and linked to conditions such as inflammatory bowel disease, obesity and metabolic disorders. Emerging research suggests that some food additives, including emulsifiers1 and artificial sweeteners,2 may exert their harmful effects through microbiota-mediated mechanisms. However, responses to dietary components are highly heterogeneous across individuals, raising an important question: Can we predict individual responses to diet based on microbiota composition and function? Such predictive capabilities could pave the way for personalised nutrition and medicine, tailoring dietary interventions to an individual’s unique microbial makeup. Despite its promise, this approach faces several challenges. Microbiota composition is highly variable across individuals and influenced by numerous factors, including diet, lifestyle, genetics and prior medical treatments. This variability complicates predicting how specific perturbations will affect an individual’s microbiota, as …