Researchers reviewing 14 clinical studies going back nearly 100 years identified a declining trend in the acidity level of faeces (measured by pH) in U.S. infants.
Writing in the journal mSphere, the team noted that in the mid-1920s the pH level of infant poo was mildly acidic at around 5.0. By 2017, a 1.5 point increase in pH had occurred.
The study, which was funded by Evolve BioSystems Inc, a spin-off from the Foods for Health Institute at UCD, noted that although a pH of 6.5 is technically still marginally acidic, this trend towards alkalinity has created an environment that allows bad bacteria such as E.coli and Clostridia to thrive in the babies gut.
This pH change has been accompanied by a significant reduction in the abundance of the beneficial bacterium Bifidobacterium, said the team from Evolve BioSystems.
The changes in microbiome make-up are largely characteristic of developed countries, whereas infants in resource-poor nations have tended to retain higher levels of Bifidobacterium and lower pH.
“This steady increase in the faecal pH of infants over the past several generations has largely gone unnoticed by the medical community, but looks to be an indication of a major disruption of the infant gut,” said David Kyle, Ph.D., Chief Scientific Officer and Executive Chairman at Evolve BioSystems.
“This may be a significant contributor to the incidence of allergic and autoimmune disorders,” he added.
Underlying causes?
The researchers suggest three main factors underlie this change in microbiome composition: the decline in breast-feeding and use of formula milk; the increased frequency of caesarean section delivery limiting the transfer of Bifidobacterium from mother to infant; and the increased use of antibiotics.
“These alarming changes to the infant gut microbiome and thus, gut environment, may be due to modern medical practices like antibiotics, C-sections, and formula feeding. These are all potentially life-saving medical practices, but have unintended consequences on the infant gut microbiome,” explained study co-author Dr. Jennifer Smilowitz, Associate Director of the Human Studies Research Program for the Foods for Health Institute at UCD.
“As a result, certain pathogenic bacteria—those linked to higher risk of health issues such as colic, eczema, allergies, diabetes and obesity¾ thrive. The need for clinicians to have a quick and reliable method to determine Bifidobacterium levels in baby’s gut, and an effective way to replace the right Bifidobacterium to correct dysbiosis when detected, are the critical next steps for infant health,” Smilowitz continued.
Detection of dysbiosis and the restoration of Bifidobacterium are currently areas of focus for Evolve.
“We are making progress in learning how to detect infant gut dysbiosis and restore the gut to its natural state through the introduction of very specific probiotics, said Kyle.
Evolve recently published results (covered by NutraIngredients) of a clinical trial, which showed positive results in restoring Bifidobacterium, reducing harmful bacteria and lowering faecal pH in infants through supplementation of their probiotic Evivo, which contains a proprietary strain of B.infantis.
Source: mSphere
Published online, doi: 10.1128/mSphere.00041-18
“Elevated Fecal pH Indicates a Profound Change in the Breastfed Infant Gut Microbiome Due to Reduction of Bifidobacterium over the Past Century”
Authors: Bethany M. Hendrick, Jennifer T. Smilowitz, Steven A Frese et al