Effect of the Sustainable Diet on Gut Microbiota and the Metabolome: a Randomised Crossover Study

Unhealthy diets are closely linked to non-communicable diseases and constitute higher risk of morbidity and mortality than unsafe sex, alcohol, tobacco and drugs use combined. According to the World Health Organization (WHO), a healthy diet follows a plant-based pattern with low quantities of red meat and a low simple sugar intake. It would also reduce anthropological ecologic impact. We hypothesize that a plant-based diet will beneficially modify the gut microbiota and metabolome, influencing also Trimethylamine N-oxide (TMAO), a metabolite associated to CVD.

This study has a randomized single blind crossover design that compares a plant-based diet towards a control western diet. It is applied to volunteers aged 18-70 years, N=20. Each dietary intervention (plant-based and western) would last for 16 consecutive days separated by a minimum of 7 weeks washout period (intervention 1-washout-intervention 2). Samples of blood urine and faeces will be collected at day 1 and 14 of each intervention. On day 14 will be performed L-carnitine challenge with 1200mg of L-carnitine to test the levels of TMAO), in for the next 2 consecutive days (24h and 48h post treatment).