Feeding Your Baby

Is Formula Poop Different Than Breast Milk Poop?


Let’s talk about infant feeding… and the poop that comes with it. You can’t have one without the other, right? Although, this time we’re not necessarily discussing what your precious baby is eating. Nope! Instead, we’re analyzing what leaves your baby’s digestive tract and how you can determine if it’s normal and healthy. We’ll even highlight the times a baby’s stool may not be deemed as wholesome. Oh the joys of parenthood!

Did you know when it comes to your baby, that digestion is just as important as the feeding process? By knowing what to look for regarding healthy digestion, you’ll be able to better understand what your baby is able to eat, how they’ll react, and how to feed them even more nutritious mixtures for their system.

Ready to dive in? Then, let’s go! 

What’s the Difference Between Breast and Formula Milk?

First, let’s talk about the different milk options babies are fed after birth and what they entail. While all options are made to work and act similarly, they really don’t have too many comparable differences. Take a look into the following to see how they differ and what main ingredients are utilized in both. 

Breast Milk

So, what does breast milk actually contain? Here are a few key nutrients:

  • Water
  • Carbohydrates
  • Lipids
  • Proteins
  • Immunoglobulins (Antibodies)
  • Hormones
  • Enzymes

Out of all of these ingredients, it’s super important for a baby to receive the antibodies necessary to fight off infection. These can create part of the foundation of your baby’s immune system. 

Formula Milk

Formula can either be a healthful supplement or a complete alternative to normal breast milk. Formulas are made to be very similar in composition and follow strict regulations from the FDA. Most formula milks contain the following ingredients:

With many similar ingredients, your baby will still receive the abundance of nutrients found in breast milk. The main difference is the antibodies we mentioned, as well as a small difference in taste your baby may not even notice. 

The Scoop on Poop: Some Guidance from Tiffani Ghere, Registered Dietician, Board Certified Specialist in Pediatric Nutrition, and Certified Lactation Educator

We asked Tiffani: Is formula poop different than breast milk poop? What formula is easier on a baby’s digestive system? 

Here’s what she had to say!

“Yes, poops from formula babies are often somewhat different in their appearance. They often have a pastier consistency and can range from green to brown to yellow. All are considered normal. Formula fed babies are reported to poop less frequently than BF babies, but by one month of age many babies are stooling less frequently, regardless of what they are fed. As long as the baby can easily poop without straining and the poop is soft, the frequency of several times a day to every 3-4 days is within the normal range. 

Formula is the first food choice parents can make for their baby. As with any food, reading the label and knowing the quality of the ingredients is important in making good choices. Most formulas have a cow’s milk base, so how that cow is raised–what it is fed, that it is not exposed to hormones or antibiotics–these all contribute to the quality of the milk in the infant formula. Having a whey to casein (milk proteins) ratio similar to breastmilk, being certified as organic and being free of artificial additives all can promote better digestibility, and a happier baby.

Thanks, Tiffani!

Your Baby’s End Result When It Comes to Digestion

No two types of formula will be digested exactly the same, and this is simply because not all of the same ingredients are present in each mixture.

Since a baby’s digestion process is a bit different for each of the formulas their little body might encounter, the end result (their poop) will also look different. 

So, let’s talk about poop! We looked at a case study that actually took a deep dive into the full digestive process, and we’re happy to share those findings with you! Take a look at the following, so you’ll know what to watch out for and when to be concerned, especially where poopy diapers are concerned!

Breast Milk Poop

While it may look a little scary and not seem right the very first time you encounter it, breastfed babies typically have more of a yellow, green, or brown color poop. Their poop can also appear seedy and pasty in texture. At times, it may also look similar to diarrhea.

When compared to other bowel movement odors, you might even sniff a whiff of a sweeter smell compared to types of formula milk poop.

Formula Milk Poop

When a baby is introduced to formula milk, you can expect to see shades of yellow or brown in their bowel movements. Its consistency won’t appear to be runny like diarrhea, but you will notice it’s pastier like peanut butter.

Babies who are given formula instead of breast milk will also not have bowel movements as frequently. Their stools can also be expected to be slightly more odorous.

What Does Newborn Poop Look Like?

A few days after birth, a baby will have a dramatically different look to their stools than at any other time. The biggest reason for this is because they are ridding their system of what they ingested during their time in the womb. 

As a result, a newborn’s stool will have a mix between a green and black appearance. It will also have a sticky consistency and will mostly resemble the look of motor oil. While it may look alarming, have no fear! It’s 100% completely normal.

This type of stool is also referred to as meconium, which is made of amniotic fluid, mucus, skin cells, and anything else that was ingested in utero.

Let’s Analyze Baby Poop by Color 

It’s completely normal for your baby to show off a few different colors from the color wheel in their stool. In fact, it should be expected. However, it can be difficult to immediately know what each one means. By following along, you’ll be able to understand what each piece of colored poop is telling you. 

Green Poop

If you gave your baby an iron supplement, then the appearance of green stool can be seen as the result. The appearance can also occur at 4-6 months after you’ve introduced green solid foods into their diet. The green coloring can also be a result of the following foods in your baby’s diet:

  • Pureed Peas
  • Spinach
  • Beans

Orange, Yellow, and Brown Poop

These fun poop colors are also completely normal and expected, especially if you’re still feeding your little one breastmilk or formula milk. As time progresses, a range of these colors will most likely be found.

It can also mean that more or less pigment is being gathered or absorbed during the digestive process.

Black Blood Poop

Wait – don’t freak out just yet! It is possible to find tiny specks of black blood in a baby’s stool. However, it may not be theirs. It could be the mother’s blood from breastfeeding, especially if she has cracked nipples. This won’t pose a threat to your baby, but it is always best to get your baby checked out by a pediatrician to make sure it’s not something more serious. 

White Poop

Now, it’s time to sit up and take notice! The presence of a chalky white coloring or even the appearance of grey in a baby’s stool is not normal. It can also pose as a warning sign that your baby may be having a more difficult time digesting their food. There could also be a lack of bile in their liver. This kind of coloring is something that should immediately be reported to your pediatrician.  

A Baby’s Poop Can Transmit Warning Signs

Now that we know what a healthy baby stool looks like, let’s switch gears and focus on what may not be considered to be healthy.  The following signs are great indicators that your baby is either not digesting their food properly, or there is an underlying condition present.

Runny Bowel Movement

If your baby’s stool consistently has a runny texture and a green, yellow, or brown color, then there may be an infection or allergy present. If you notice this, time is of the essence. Don’t wait too long to get it checked out. Waiting could cause dehydration for your infant.

Hard, Small Stones

Does your baby’s poop have a hard, rough texture? Your baby may be undergoing constipation. Their stool will not only appear hard, but it will also be in the shape of small pebbles.

This often happens as your baby is being introduced to more solid foods. The digestive system might not be ready to take on these types of foods as a result. If they’re still taking in milk, then there could be a sensitivity to lactose or soy, which is an indication that they may have an intolerance.

Appearance of Blood in Stool

It’s normal for a baby’s poop to reflect the color of what they previously ate. However, it should be monitored regularly. For instance, if there is a red color present in your baby’s stool after ingesting formula, then it could be blood that’s being seen.

If this is the case, then it could mean there is a bacterial infection present, your baby may have a food allergy, or there could be another underlying condition, and you should take your baby to their doctor for further direction. Occasionally, with harder stools as they get older, there may also be the possibility of a small tear in the anus while they were passing the stool, which will look a bit more like streaks on top of the stool than blood in it. 

There could also be the occasional presence of slimy, green-colored streaks in the midst of your baby’s stool. This could be a sign of your baby fighting an infection.

If you happen to notice any of the above signs, be sure to partner with a doctor immediately for further information and an ultimate diagnosis. The health and safety of your baby is vital, so it’s important to take swift action if you feel your baby’s poop is abnormal or warrants a second opinion.

Our Final Thoughts

Clearly, the body works in wonderful and magical ways, and the appearance of stool happens to be one of them. Not only does a baby’s body show how they’re digesting food and nutrients, but it also gives warning signs when something doesn’t appear to be right, so you, as a parent, can take charge!

Whether you choose to feed your baby breastmilk or formula milk or even both, your baby will be receiving the nutrients they need to thrive. Don’t forget to always partner with a medical professional to ensure that all signs your baby’s poop are giving are pointing in a positive direction. Because every parenting milestone is magical, even when it comes to exploring the ever-changing wonders of your baby’s poopy diapers!  


1.      https://www.thebump.com/a/baby-poop

2.      https://www.unitypoint.org/peoria/article.aspx?id=bf220648-fad4-4523-8046-ae084e66a92a

3.      https://www.verywellfamily.com/whats-in-breast-milk-4047820

4.      https://www.medela.com/breastfeeding/mums-journey/breast-milk-vs-formula

The content on this site is for informational purposes only and not intended to be a substitute for professional medical advice, diagnosis or treatment. Discuss any health or feeding concerns with your infant's pediatrician. Never disregard professional medical advice or delay it based on the content on this page.

The content on this site is for informational purposes only and not intended to be a substitute for professional medical advice, diagnosis or treatment. Discuss any health or feeding concerns with your infant’s pediatrician. Never disregard professional medical advice or delay it based on the content on this page.

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