Other researchers are also interested in exploring the function of the diverse bacteria found in the Yanomami, to see if these microbes train their children’s immune systems early and if they are protective against autoimmune diseases on the rise in industrialized populations. One type of gut bacteria, Oxalobacter, found in the Yanomami is already known to protect humans from the formation of kidney stones. “I think these missing microbes are at the root of many Western diseases,” says microbiologist Justin Sonnenburg of Stanford University in Palo Alto, California, co-author of the forthcoming book The Good Gut: Taking Control of Your Weight, Your Mood, and Your Long-term Health. “The big message is we in the Western world have lost the diversity in our microbiota. We have to study these groups to figure out what we lost, what these microbes do, and how we get back to a healthy microbiota.”