"Decline of Plant Digestion in Urban Humans"
A new study indicates that urban living has caused a significant decrease in the number of cellulose-digesting bacteria in the human gut, while rural populations and hunter/gatherers still maintain a higher prevalence due to their high-fiber diets. The research found that humans host a mix of cellulose-eating bacteria, some inherited from primate ancestors and others acquired through the domestication of herbivores. The study also revealed that the prevalence of these bacteria is changing with changes in human diet, and the more fiber in a culture's diet, the more diverse their cellulose-digesting bacteria are. The findings suggest that while humans lack specialized structures to digest cellulose, these bacteria may still make critical contributions to our health.