Babies Poop Smells Like Vinegar- Is It Normal?

baby with vinegar smelling poop being changed

Why does my babies poop smell like vinegar? Becoming a parent changes your world—even the things you never considered important become significant to you.

You never thought a discussion on babies’ poop was relevant, right? Now, any unexpected change in your baby’s poop will have you enquiring about its normalcy.

Ever gave a thought to why your little one’s poop has a vinegary smell? Is this even normal? Let’s find out.

babies poop smells like vinegar

Why Does Your Babies Poop Smell Like Vinegar?

As your baby’s diet changes, there will also be changes in the smell and texture of the poop.

What starts as a sticky meconium poop that is greenish-blackish in color and odorless becomes a solid mass that can be quite smelly.

As the poop texture and smell evolves, vinegar smelling baby poop is not a regular occurrence. It could be a sign of some kind of digestive issues your baby might be having. These may include;

Lactose Intolerance

One of the most common reasons why breastfed baby poop smells sour is lactose intolerance. Your baby’s tummy can be sensitive to milk or other dairy products.

If you are breastfeeding, a dairy product you ate before breastfeeding can also affect your baby. Other symptoms of lactose intolerance to look out for include bloating, gas, and diarrhea.

SEE ALSO: 12 Foods To Avoid While Breastfeeding To Prevent Colic

Bad Gut Flora

The human gut contains millions of bacteria and microorganisms referred to as gut flora. This flora is essential for your general health and well-being.

During birth, your baby’s “good” bacteria is disrupted, resulting in the multiplication of bad gut flora from an early stage.

The bacteria in your baby’s gut can also be affected by diet, lifestyle, and the environment, leading to that sour-smelling poop.


The food your baby consumes is absorbed in the digestive tract. But, if the absorption process does not go well, it may result in your baby’s poop having a sour odor.

Common causes of mal-absorption are viruses, parasites, infections, and some disorders.

Food Sensitivity

Trying out new foods for babies is exciting. However, it brings a new set of challenges. As your baby learns new textures and flavors, food allergies and sensitivities also crop up.

You may also come to learn that some foods are difficult to digest for their tiny tummies. Sensitivity to some foods will result in baby’s poop smelling like vinegar.

Some kids find a variety of foods difficult to digest. Such foods include: nuts, soy products, dairy products and eggs.


Rotavirus is contagious. It’s been known to result in inflammation mainly inside the stomach and the baby’s intestines.

Symptoms of the virus include excessive diarrhea, vomiting, fever, pain, and dehydration. The poop will have a sour vinegar-like smell.

Crohn’s Disease

This inflammatory bowel disease results in soreness of the digestive tract.

Symptoms include foul-smelling and bloody diarrhea, fever, fatigue, stomach cramps, mouth sores, and loss of appetite.

Cystic Fibrosis

The disease is hereditary and results in mucus clogging the lungs and the digestive tract. It may also cause your baby’s stool to smell like vinegar.

Other symptoms associated with the disease are a phlegmy cough, lung infections, poor weight gain, fatty stool, and difficulty in bowel movement.

Cystic fibrosis is usually screened for at birth, so you are likely to know whether your baby has the disease from the onset.


Although there are no scientific studies to back this up, some parents have noticed that their babies’ poop smells like vinegar during teething.

SEE ALSO: Complete Buyers Guide On Best Baby Teething Necklaces

baby with vinegar smelling poop being changed

What else should you lookout for

In assessing your baby’s gut health, apart from vinegar-smelling poop, other symptoms will tell you there is a more severe problem. These include:

  • Fever
  • Vomiting
  • Stomach pains
  • Irritability
  • Dehydration (dark or infrequent urine)
  • Shortness of breath
  • Frequent watery poop, more than 6 times in 24 hours
  • Bloody poop
  • White, red, or black poop

These signs should alert you to seek medical attention for your baby immediately.

What To Do When Baby’s Poop Has That Sour Vinegar Smell

Your baby’s diaper business is your business. It’s normal for your baby’s poop to smell foul from time to time, depending on new changes in their diet or yours if breastfeeding. 

When introducing new foods to your baby’s diet, pay attention to any changes in bowel movements. While variations in texture, color, and smell are expected, any acidic smell should raise alarm bells.

Food that your baby is sensitive to will be challenging to digest and should be immediately removed from their diet.

If you feel there is cause for concern about that unusually foul-smelling poop, visit a pediatrician to allay any fears. You can never be too careful when you’re dealing with anything to do with your baby’s health.

Although we have established that the reasons for poop smelling like vinegar can be minor, tests can reveal something more serious. Early diagnosis is essential to the treatment or control of any disease or virus.

What is Normal Baby Poop?

Normally, full-term babies poop for the first time in the 48 hours after their birth. The greenish-blackish meconium contains what the baby consumed before birth.

It will also have amniotic fluid as well as bile and fluids emitted out of the baby’s intestinal glands. 

Meconium is odorless as is generally sterile and should clear out of your baby’s system after a couple of days.

When feeding begins, bacteria are introduced into the baby’s gut, marking the beginning of the poop evolution. Breastfed babies will have a watery, mustardy stool that contains what looks like tiny seeds. Nizagara

Formula-fed babies will have a pasty stool that can be yellow, tan, or green. If your baby’s poop has earth-tone colors, it shouldn’t be any cause for concern.

A breastfed baby’s poop is odorless but may have a sweet scent. Formula-fed babies may have a smelly poop, but not overwhelmingly so.

The real diaper bombs begin when the baby transitions to solid foods, and the poop consistency also solidifies.

SEE ALSO: Can You Use A Diaper Genie For Depends?

How Often Do Babies Poop?

Gastrocolic reflex is a natural human reflex that informs your colon to empty food once it gets to your stomach to make room for more.

This reflex is highly active in babies, which makes them poop a little every time they feed. Over time, it becomes less active, and the passage between eating and bowel movement becomes regulated.

During the first few months, expect to have at least 10 diaper changes per day. The bowel cycle should reduce to between 2 and 4 changes per day once the baby reaches the 4-month milestone.

As babies grow, some babies’ intestines absorb so much milk that bowel movement is reduced to once a day or even once a week. This means that it’s entirely normal for a breastfed baby to poop once a week or after feeding.

For formula-fed babies, this may be different as poop moves slower through the intestines with formula. Therefore, it is normal for the babies to have one or two bowel movements every other day after the first few months.

Babies that are both breastfed and formula-fed will have a bowel cycle ranging from multiple times per day to once per week.

A baby wearing diapers


As babies grow, they will be exposed to different diets and environments, which will affect their gut health and bowel movement.

Babies’ poop smelling like vinegar will happen a lot more than you may think. Don’t panic if your baby’s bowel movements suddenly have a sour smell.

Evaluate the causes and check for other symptoms so you can decide whether it’s just a dietary adjustment that’s necessary or you need to seek medical advice.

Ultimately, nobody knows your baby entirely as you do, trust your instincts and act as you see fit when it comes to your baby’s health.


why does my babies poop smell like vinegar


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