In the last post we looked at some reasons that newborns get fussy and when to call or visit your baby’s doctor. Now we’ll dive deeper into colic, spitting, and constipation, and look at how diet can make a difference.

There are many reasons a baby might cry, but a lot of fussiness seems to start in the tummy (the GI tract). Parents usually notice that colicky babies draw up their legs and seem to have stomach pain, but the things we have traditionally done to treat gastroesophageal reflux disease (GERD) and milk protein intolerance — antacid medications, formula changes, positioning — seem to help well under 5% of colicky babies. One theory was that colic was just part of having an immature nervous system, and maneuvers like rocking, swaddling, sucking, shushing, and side-lying (on a parent’s lap, awake) seem to help some, but they’re labor intensive and may not produce lasting relief.

Now, however, we are learning that generations of parents were right: colic does involve the intestines, just not how we had imagined. Our best evidence looks at the vast world of microorganisms that live in and on us, our microbiome. These cells outnumber our own by about 3:1, and we are only now beginning to learn what they do for (and to) us.

Probiotics and HMO’s: Beneficial bacteria and what helps them grow

When it comes to infants, many of our studies focus on two species of intestinal bacteria, Bifidobacterium lactis and Lactobacillus reuteri (B lactis and L reuteri for short) and one component of human breast milk that seems to be there to feed these bacteria, human milk oligosaccharides (HMOs). Evidence is growing that these elements can improve babies’ digestion and immune function and reduce crying, spitting, and uncomfortable stools.

You might imagine that human breast milk would be sterile, but in fact mother’s milk contains bifidobacteria, and they are the most commonly identified bacteria in babies’ intestines. Infants born by c-section have lower counts of bifidobacteria than those born vaginally, probably because they don’t pass through the vaginal canal. Studies show that probiotics, like Bifidobacterium lactis  (B.lactis) plays a role in supporting babies’ immune function, increasing levels of an antibody that protects the intestines (IgA) and promoting the development of white blood cells that help fight off disease (T-helper cells). B lactis also seems to strengthen the barriers between cells that line the intestine and increase the production of protective mucous in the gut.

Colic and Probiotics

Of all the intestinal bacteria we have studied, L reuteri has shown perhaps the most promise in helping to treat colic. L reuteri supplementation reduced crying time and fussiness in colicky infants in multiple studies, and it also lowered the frequency of spitting up. It even seems to help constipated babies have more frequent bowel movements.

Human breast milk includes two kinds of sugars, lactose and HMO’s. Lactose is the perfect carbohydrate for babies, and it is in all breastmilk. But alongside that lactose is an abundance of HMO’s, carbohydrates that babies cannot digest and that barely make it into the bloodstream. What can digest HMO’s? Bifidobacteria! For this reason, HMO’s are also called “prebiotics.” HMO’s can also bind to harmful bacteria in the intestines, keeping them from invading. The HMO’s that do make it into the bloodstream have a role in promoting healthy immune system development. HMO’s are also one reason that breastfed babies have softer stools than those on formula.

Many aspects of modern childbirth seem designed to disrupt babies’ microbiome. Just under a third of babies are born by c-section, meaning they never encounter the normal vaginal and rectal organisms that help them build a healthy gut. Antibiotics have saved countless lives by preventing newborn sepsis, but they also have an effect on mom’s and babies’ microbiome. Many formulas lack the bacteria and HMO’s found in human milk.

As we discussed in the last post, some degree of fussiness and spitting is normal. If you can, exclusively breastfeeding is the ideal way to promote a healthy microbiome for your baby. But breastfed babies also can spit excessively, have hard stools, and become colicky. If you’re breastfeeding, you can try giving your baby drops that contain B lactis and/or L reuteri. If you’re supplementing with formula or formula feeding, consider choosing a formula with probiotics and HMO’s like Gerber Good Start Infant Formulas. And, as always, if you have questions or concerns about your baby, call your doctor’s office for advice!

* #Sponsored. Dr. Hill is a paid consultant to Gerber.

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