Fortunately, Dr. Anish Sheth has seen it all. A gastroenterologist who, we kid you not, goes by the nickname “Dr. Stool”, Sheth has just released his new book The Complete What’s Your Poo Telling You. It’s an exhaustive guide to what comes out of the human butt, and while it may not be the poop guide we deserve, it’s surely the poop guide that we need. Fatherly spoke with Dr. Stool about what even amateur scat spotters can keep an eye out for during diaper changes: When my kid was born, I kind of knew that the first poops would be different, but I was totally unprepared for the strange sticky substance that came out of him. What’s going on there? Newborn stool is black. It’s surprising the first time you see it because, as adults, we’re not used to seeing that shade of stool. It’s called meconium. It’s basically the waste from 9 months of being in utero and it’s actually a really good sign that the baby is healthy and that their intestines are working properly. What’s weird is that it wasn’t smelly. And I kind of feel like that’s a mean trick. I was lulled into the idea that this wasn’t going to be so bad. One of the things about meconium is that it looks dramatic but there’s no odor. There’s a simple explanation. The odor of most of the things in our body come from bacteria. Newborn baby intestines are actually sterile. The first couple of stools really have no smell at all. So enjoy it while it lasts. And it doesn’t last. Things change pretty quickly. Why does it change? And does it matter if a baby is breastfed or formula fed? If the baby is breastfed you get a yellow, seedy, sweet-smelling stool, which can last as long as the breastfeeding lasts. For those babies that are formula fed things tend to become more odoriferous sooner and the stool takes on more of a greenish hue, particularly with iron-fortified formula. So when should parents expect to see poop that looks like what they’re more familiar with? Once the baby is eating regular food it’s basically going to be brown from there on out. That can be around six months at the earliest. So black and color changing poop is normal. Would be easier to talk about what’s definitely not normal? Anytime you see red, that looks like blood in the stool, it should be followed by a call to a pediatrician. Leaving color aside, volume is important. Voluminous diarrhea is certainly concerning because babies could become dehydrated quite easily. On the other side, babies not having bowel movements over a 24-hour period or so can be a sign of issues particularly early in life. With any of these problems, will probiotics help? I think that any kind of supplement should come with healthy skepticism. We have to be careful. There’s no study or evidence that healthy kids who are feeding and growing well having adequate bowel movements that probiotics have any benefits. There are specific medical conditions where probiotics have been studied and have seen good evidence that they are safe and effective for certain conditions. When parents see something wrong, what should their first course of action be? Don’t be afraid to use your cell phone and take a picture. Document what you’re seeing so they don’t have to guess what’s going on. You have a nice palette. A nice white diaper in the background. You don’t have to worry about lighting. It comes down to how they appear overall. If the baby has a high fever and seems less active, then a change might signify something important. But if they seem fine otherwise, you can wait for the next stool. You won’t have to wait long.