Did you know that breast milk has components that aren’t even digestible to infants? These compounds are known as human milk oligosaccharides (HMOs) and are thought to be just for the purpose of ensuring the right bacteria get in the infant’s gut by serving as a substrate only a few co-evolved microorganisms are specially evolved to utilize efficiently (or more efficient than others at least). They also shape the immune system and have been shown to protect against obesity. This is an awesome area of research, and, as you might’ve expected, not something that has yet been replicated in infant formula. Learn more about HMOs (at 37:14) and much, much more about the human gut microbiota with this video interview featuring Justin and Erica Sonnenburg, authors of The Good Gut.