Gut bacteria important for digestion and also avoiding disease

US News & World Report - Gut bacteria reflect dietary differences 

Scientists studied the two groups of children, those from a western, developed nation (Italy), and those from a 3rd-world African country (Burkina Faso). Scientists looked at diet, as well as the microbes and bacteria in the guts of the children. During breast feeding, the children's guts looked similar, but as the diets diverged, changes in gut flora began. In the rural, 3rd-world country where  the diet was mostly legumes, vegetables and grains (and little animal protein or fats), the children's guts contained greater floral diversity, increased bacteria that digested fiber, including some bacteria that termites share. The conjecture is that these bacteria provide for greater digestion of plant fibers. The Burkina Faso children also had less diarrhea-causing bacteria, even though they drink water more likely to be contaminated with it. The conclusion is that gut microbes and bacteria can be acquired through diet, that many have been lost in the western diet, and that it such bacteria are not just influential on energy and digestion but also on the immune system.