Most of us do our best not to think too much about baby poop. But, as it turns out, stool has a lot more power than we think—and not just in terms of its pungent smell. Our poops can say a lot about our health, and that's true from the first time we soil a diaper.

Recently, researchers have found that the bacteria that live inside our guts—known as the microbiome—are crucial to keeping us healthy. But understanding which bacteria help and which hurt—and how we can maintain a gut full of "healthy bacteria"—is still something that scientists are figuring out. Studying an infant's stool might be a key way to do so.

During the first year of life, as a baby is growing, their intestines are fostering a nursery of bacteria. Those microbes are important in that they help to digest food and create a healthy immune system. But our microbiomes may not be as healthy as they once were.