By: Maggie Fox

Baby poop is changing, and that could be bad news for children’s health.

Anyone with a newborn knows that baby poop is important. Pediatricians often ask parents of a new baby to keep track of what’s in their diaper, to make sure they are eating properly and that everything’s working as it should.

A new report published Wednesday finds that baby poop can tell us more than just how one infant is doing.

The study found that the pH, a measure of how acidic or alkaline something is, has been steadily going up since the 1920s.

This matters because acidity can tell doctors about the baby’s microbiome — the balance of “good” bacteria that help digest food and protect us from disease.

The researchers think it may also help explain the rise of allergies and asthma in the modern era.

Bethany Henrick of the University of Nebraska and Evolve BioSystems Inc. looked at medical studies of baby poo going back to 1926, when researchers first started characterizing the bacteria in infant feces.

“A review of 14 clinical studies published between 1926 and 2017, representing more than 312 healthy breastfed infants, demonstrated a change in fecal pH from 5.0 to 6.5,” they wrote in their report, published in the journal mSphere.

A low pH indicates a fluid is more acidic, while anything with a pH of 7 or higher is considered more alkaline.

The change has accelerated since 1980, they added.

Studies indicate that pH can be a quick way to measure whether an infant’s digestive system has enough beneficial bacteria from a group called Bifidobacterium. When these bacteria break down milk, they produce acids and that acidity shows up in the baby’s waste.

There’s one particular species of Bifidobacteria that indicates a healthy gut. It’s called B. infantis. Babies with plenty of B infantis produced dirty diapers with more acidity than babies lacking in this bacteria, the researchers said.

Everyone carries a microbiome — a population of microbes such as bacteria and yeast that affect all sorts of functions, from absorbing food to immune response.

Read the full article here on Today.com.