Mbakwa CA, et al. - In school-aged children, experts assessed the intestinal microbiota composition in relation with being overweight. Using the Human Intestinal Tract Chip, the fecal microbiota composition of 295 children was analyzed. This was the largest population-based study on childhood gut microbiota and body weight so far. The present data indicated that Prevotella melaninogenica, Prevotella oralis, Dialister, and uncultured Clostridiales II (UCII) accounted for 26.1% of the variation in microbiota composition. Findings suggested no significant association of microbial diversity and richness and Bacteroidetes to Firmicutes ratio, with any of the outcomes, while Streptococcus bovis was positively associated with being overweight. An association of both new and previously identified bacterial groups with overweight was seen.