Common household cleaning products could be making children overweight by altering their gut bacteria, scientists say.
A Canadian study published in the Canadian Medical Association Journal analysed the gut flora of 757 infants from the general population for their exposure to household disinfectants, detergents and eco-friendly products.
According to the study, the frequent use of products such as multi-surface cleaners had a strong association with altered bacteria.
This association was not there with detergents or eco-friendly cleaners, according to the scientists, who added that piglets have also exhibited similar changes in their guts when exposed to aerosol disinfectants.
“We found that infants living in households with disinfectants being used at least weekly were twice as likely to have higher levels of the gut microbes Lachnospiraceae at age 3-4 months,” said Professor Anita Kozyrskyj, senior author of the study.
This meant that “when [the children] were three years old, their body mass index was higher than children not exposed to heavy home use of disinfectants as an infant,” added Professor Kozyrskyj.
Babies that lived in households that used eco-friendly cleaners had different microbiota and were less likely to be overweight as toddlers, the study found.
“Those infants growing up in households with heavy use of eco cleaners had much lower levels of the gut microbes Enterobacteriaceae. However, we found no evidence that these gut microbiome changes caused the reduced obesity risk,” she said.
Professor Kozyrskyj suggested the use of eco-friendly products may be linked to being healthier overall which was reflected in the gut microbiomes, rather than causing it.
“Antibacterial cleaning products have the capacity to change the environmental microbiome and alter the risk” for childhood obesity, write the authors.
“Our study provides novel information regarding the impact of these products on infant gut microbial composition and outcomes of overweight in the same population.”
In a related commentary, independent scientists have provided perspective on the study’s findings.
“There is biologic plausibility to the finding that early-life exposure to disinfectants may increase risk of childhood obesity through the alterations in bacteria within the Lachnospiraceae family,” write the epidemiologists Dr Noel Mueller and Moira Differding, of the Johns Hopkins Bloomberg School of Public Health.
The pair have called for further studies “to explore the intriguing possibility that use of household disinfectants might contribute to the complex causes of obesity through microbially mediated mechanisms.”
Professor Kozyrskyj agreed with their perspective, and said studies in the future need to classify cleaning products by their ingredients: “The inability to do this was a limitation of our study.”