Healthy children in Europe have different gut bacteria than healthy children in Africa, because of their very different diets, and this may explain the prevalence of intestinal disease and allergies in the West:
A team of researchers led by Paolo Lionetti, a pediatric gastroenterologist at Meyer Children Hospital in Florence, Italy, decided to compare the fecal microbes of healthy children from a village in Burkina Faso, in western Africa, with those from healthy Italian children. The African children ate a high-fiber, low-fat, vegetable-heavy diet that reflects what people ate at the dawn of agriculture, whereas the Italian kids had a typical Western diet, low in fiber but high in animal protein, sugar, starch, and fat.
The researchers found that the children from Burkina Faso had significantly more bacteria from the Bacteroidetes class than did the Italian children and significantly fewer Firmicute bacteria. Previous research has shown that people with more Bacteroidetes and fewer Firmicutes tend to be lean, whereas people with the opposite ratio are more likely to be obese.
Additionally, the researchers detected bacterial strains of Prevotella, Xylanibacter, and Treponema only in the children from Burkina Faso. These bacteria are excellent at breaking down fibrous foods and producing short-chain fatty acids that provide added energy. Studies have also shown that those same fatty acids help protect the intestines from inflammation, which could explain why inflammatory bowel disease is almost unheard of in African communities that eat high-fiber diets, Lionetti says.
The increased diversity of microbes in the gut also makes the body more resistant to intestinal pathogens while tempering the immune system’s response to harmless molecules, leading to fewer allergies, Lionetti says. The group reports its findings online today in the Proceedings of the National Academy of Sciences.
(Hat tip to Buckethead.)