Some of our key gut microbes likely came from cows —and we’re losing them

This study revealed that the specific cellulose-degrading bacterial strains have declined over the centuries and even disappeared in many people in industrialized societies, most likely because diets there tend to contain less cellulose, which these microbes need to thrive. More than 40% of ancient human samples had these bacteria, as did one in five modern hunter-gatherers and rural dwellers. But fewer than one in 20 of people from places such as Denmark, Sweden, the United States, and China have them, the team reports. Those who do have these microbes tend to have just a single species, and relatively low numbers of it. Without these bacteria, however, digesting cellulose would be very difficult, if not impossible, the researchers say. “The bottom line is that [because of] industrialization, we seem to have lost a huge diversity of microbes in our gut,” says Tom Van de Wiele, a microbial ecologist at Ghent University. “By depriving our diets [of] dietary fibers, we lose the microbes that help us in obtaining a better gut health.” However, Bernard Paul Henrissat, a biochemist at the Technical University of Denmark, says more work is needed to be sure cellulose is really being broken down humans’ guts, and if so, by which species of bacteria. Eric Martens, a microbiologist at the University of Michigan Medical School, also questions whether these bacteria are working the same way as they do in cows. Ruminants need a very long time to break down raw cellu...
Source: Science of Aging Knowledge Environment - Category: Geriatrics Source Type: research