Key words: obesity, microbiota, therapy

There is an elevated incidence of cases of obesity worldwide. For the first time in human history there are more obese people in the world than underweight people. Therefore, the development of strategies to tackle this condition is of vital importance. The potential role of gut microbiota in obesity has recently emerged as a promising therapeutic tool. This PhD project aimed to contribute to know what the impact of the gut microbiota is on obesity when fermenting different indigestible dietary compounds. Furthermore, it helped to elucidate the potential of modifying an obese gut microbiota into a leaner profile.