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Why Is My Baby’s Poop Green?

Why Is My Baby’s Poop Green?

Green poop is typical in babies, but sometimes it could indicate an allergy or illness.

If you’ve changed your baby’s diaper and been surprised by poop in shades of dark green, light green, or anything in between, you may wonder if you should be worried. In most cases, no. What does it mean if your baby’s poop is green? There are quite a few reasons why a healthy baby could have green stools. Read on to get the scoop on green poop.

Is it normal for my baby’s poop to be green?

It can be disconcerting to discover an unexpectedly green poop-filled diaper. But it's actually a normal color variation of stool and is typical for babies. What causes green poop, and is it ever a cause for concern? Let's take a look.

Newborn green poop

Your baby’s first bowel movements will be tarry, sticky, and appear brown, black, or very dark olive green. This stool is called meconium, and it’s composed of fats, proteins, mucus, amniotic fluids, and other material consumed while in utero.

Two to three days after birth, you’ll notice that your newborn’s stools are greener and less sticky, gradually transitioning to yellow or tan.

Green poop in breastfed babies

As your baby starts to digest breast milk, their stool will be seedy and somewhat runny. It may be green, mustard yellow, or brown. Mom’s diet could play a role—did you have green juice yesterday or eat a spinach salad? You may notice similar green colors in your baby’s diaper.

Don’t be alarmed. Your little one can have green poop after mama eats leafy green veggies or foods with green food coloring.

Green poop in formula-fed babies

Green poop is typically more common in babies who are formula-fed. The added iron in many formulas sometimes leads to dark green or greenish-black stools. Formulas with protein hydrolysate, often given to babies with milk or soy allergies, may also cause green poop.

Green bowel movements after eating solid foods

Stay tuned. As your baby grows and begins to eat solid foods, the green poop may continue. Keep an eye out for stools that resemble the pureed peas or other green veggies that are introduced to their diet.

Other causes of green poop in babies

Certain medications

Antibiotics taken by either the baby or the nursing mom can temporarily alter gut bacteria. This change could turn stools greenish but isn’t a cause for concern.


Is your baby teething? Those incoming teeth can make your baby produce extra saliva, which may irritate the belly and sometimes turn poop green and mucousy.

Iron supplements

Iron supplements and iron-fortified formulas are frequent causes of dark, green-tinted stools. Again, this is typical, and it's important that your baby gets the iron they need to help support growth, immunity, and brain and motor development.

Mom changing newborn's diaper

Is it normal for my baby’s poop to be green?


When to contact your doctor about your baby’s green poop

While there are many natural and expected reasons your little one may have green poop, sometimes a call to the doctor is recommended.

When you suspect a milk allergy

If your baby has loose stools several times a day, you may want to consider the possibility of a cow’s milk protein allergy (CMPA). The poop may be green or brown, foul-smelling, and tinged with blood.

Cow's milk protein allergy, the most common food allergy in infants, is when your baby's immune system triggers an adverse reaction to the proteins in cow's milk. Most infant formulas have this protein, which is why CMPA is more prevalent in formula-fed babies. However, breastfed babies could have an allergic reaction to the cow’s milk protein in mom's diet.

In addition to green diarrhea, a baby with CMPA could also experience the following:

  • Vomiting
  • Lip and facial swelling and swelling around the eyes
  • Skin issues such as eczema
  • Spit-up
  • Gas and fussiness
  • Colic
  • Runny nose
  • Cough or wheezing

Talk to your pediatrician if you think your little one could be allergic or sensitive to cow’s milk. If you are using infant formula and your doctor identifies CMPA, they may suggest switching to a hypoallergenic formula such as Nutramigen LGG* Infant Formula. Don’t change formulas without first consulting your healthcare provider. Not all hypoallergenic formulas are right for every infant, and your doctor will help guide you to the right cow’s milk alternative for your child.

If your baby is nursing, mom will likely need to cut dairy from her diet.

Fortunately, by monitoring your baby’s issues and making some dietary adjustments, successful CMPA management is possible, and many little ones outgrow it.

When there’s a fever

If your baby has green bowel movements and a fever, calling your pediatrician is a good idea. These could be indications of a stomach bug or cold.

When there’s prolonged diarrhea

Babies with diarrhea can often have green poop. Some viruses may also cause green diarrhea with mucus. While this is common, call your pediatrician if your baby has severe diarrhea that lasts more than one or two days, is showing indications of dehydration, or if fever and fussiness accompany the diarrhea.

What to do about green poop

As always, trust your intuition. While green poop doesn't usually indicate a serious health issue, reach out to your doctor with any questions or concerns. They are there to support you as you navigate your baby’s health. And if your doctor identifies a cow’s milk protein allergy, ask them about Nutramigen LGG* Infant Formula, a hypoallergenic formula clinically shown to manage colic due to cow's milk protein allergy fast, in as quickly as 48 hours.** Nutramigen LGG* can also help reduce the incidence of future allergy challenges, while still providing the nutrition your baby needs for healthy development. Learn more about Nutramigen LGG*.



*LGG is a registered trademark of Chr. Hansen A/S
**Studied before the addition of DHA, ARA, or LGG.

All information on Enfamil, including but not limited to information about health, medical conditions, and nutrition, is intended for your general knowledge and is not a substitute for a healthcare professional's medical identification, advice, or management for specific medical conditions. You should seek medical care and consult your doctor or pediatrician for any specific health or nutrition issues. Never disregard professional medical advice or delay seeking medical treatment, care, or help because of information you have read on Enfamil.