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Posts from the ‘Science’ Category

The science behind the AAP’s safe sleep recommendations

You've probably heard about the AAP's updated safe sleep policy by now, but you might have wondered about the evidence behind it. Here's some science to answer your questions.

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The EAT Study: More food for thought on earlier introduction of solids to prevent food allergy

A recent study found that babies that started eating peanut, wheat, dairy, eggs, fish, and sesame by 3-4 months had a lower rate of food allergies. But it also calls into question whether this protocol would be appropriate or even possible for all babies.

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What’s Up With the Virgin Gut? Do Babies Really Have an “Open Gut” Until 6 Months of Age?

There is a persistent myth about infant gut development that comes up in nearly every online discussion of starting solid foods. It’s the myth that infants have a “virgin” or “open” gut until around 6 months of age. I’ve received so many emails, Facebook posts, and comments about the virgin gut over the last few years that I thought it was finally time to take a look at the science – and lack thereof – behind this myth.

I have written before, in my book and on my blog, about the controversy around when to begin introducing solid foods to a baby. Some health organizations recommend 6 months of exclusive breastfeeding, while others recommend starting to offer solids between 4 and 6 months, following baby’s cues of readiness as your ultimate guide. Based on my analysis of the most current science, I believe that the second approach is more evidence-based and helps parents to focus on their baby’s unique development rather than the calendar. I also think that it’s just fine to wait until 6 months if that is your preference.

However, whenever I discuss this science, someone lectures me about infant gut development, and they usually send me a link to KellyMom’s page on the topic, which urges parents not to offer solids before 6 months. Here’s what it says:

“In addition, from birth until somewhere between four and six months of age babies possess what is often referred to as an “open gut.” This means that the spaces between the cells of the small intestines will readily allow intact macromolecules, including whole proteins and pathogens, to pass directly into the bloodstream. This is great for your breastfed baby as it allows beneficial antibodies in breastmilk to pass more directly into baby’s bloodstream, but it also means that large proteins from other foods (which may predispose baby to allergies) and disease-causing pathogens can pass right through, too.”

Wow, that does sound scary! I can see how this “open gut” idea would worry parents approaching the transition to solid foods. But here’s the thing: There are no references given to support these statements, and in all my reading of the research literature on readiness for solids, I have not encountered science backing this concern. Yet somehow this idea of the open gut comes up over and over in online discussions, complete with judgment for parents who offer solids before 6 months and non-evidence-based suggestions about how to “heal” a baby’s gut. All of this only serves to increase anxiety in parents, which is the last thing any of us need.

It’s time to get to the bottom of this. Let’s look at some science…

What do we mean when we talk about an “open” or “closed” gut? How do we measure this? Read more

My Sleep Mantra and BabyM’s Sleep Story

BabyM is almost 14 months old already. It’s crazy how quickly the first year of his life flew by, and I know the subsequent years will be no different.

The upside of that passage of time is that we’re all sleeping pretty well now, and that is a wonderful thing. To be honest, though, I actually enjoyed watching my baby’s sleep develop this time around. I know that time softens my memories, but I already miss those quiet middle-of-the-night feedings with my baby.

Long-time readers of this blog know that I wrote a lot about sleep when Cee was a baby, in the early days of the blog. I also wrote about evidence-based sleep strategies for my book. I’ve read hundreds of papers on sleep since Cee was a baby, and that changed so much about my approach to M’s sleep. Lots of readers have asked me about how M’s sleep went, so I finally wanted to share his sleep story. Read more

Resources for an Evidence-Based Pregnancy

Pregnancy can be incredibly overwhelming. How do we sort through the huge amounts of advice - solicited and not - to make evidence-based choices? Who do we trust? Readers offered their suggestions on my Facebook page, and I've compiled them into a handy list for you!

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Are the Ingredients in the Newborn Vitamin K Shot Safe?

The newborn vitamin K shot prevents rare but potentially devastating vitamin K deficiency bleeding (VKDB). If you're concerned about the ingredients in the shot, I've investigated the science behind each one so that you can understand why it's included in the shot and why it's safe for your baby.

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Learning to Crawl Disrupts Infant Sleep (Or, Science Confirms What We’ve Already Observed)

Sometimes, when you're going through a rough patch with your baby's sleep, it helps just to know that it's normal. A recent study published in Monographs of the Society for Research in Child Development helps in this regard, because it shows that when babies learn to crawl, they have a harder time sleeping during the night. I write about the study and about my own experiences with sleep disruptions in late infancy.

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5 Evidence-Based Tips for Your Baby’s First Shots

5 important things to know before your baby's first shots - supported by science!. Find out science-based ways to reduce your baby's discomfort and what to expect afterwards.

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The Science of Mom: An Introduction

Get a sneak peek at my book, The Science of Mom! You can read the entire Introduction here!

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