“In recent decades our microbiomes have been altered by poor dietary habits; overuse of disinfectants, antibiotics, and other germ fighters; dwindling contact with vital environmental microbes, including those carried by wildlife and livestock; and the rise in cesarean section births, which don’t immerse babies in the valuable bacteria found in the birth canal. According to one 2015 study, Americans’ microbiomes are about half as diverse as those of the Yanomami, an isolated Amazonian tribe.” Bloomberg: Germ-Killing Brands Now Want to Sell You Germs.