According to the study published in the American Society for Microbiology, research indicated that the gut microbiota composition at 2 years of life is associated with body mass index (BMI) at age 12.
In addition, the BMI (body mass index) at age 2 was not significantly higher in children who later became overweight/obese, indicating that gut microbiota composition may be the earliest warning sign for detecting obesity.
“The gut microbiota might play an important part of the obesity prediction algorithm, to identify at-risk kids early in life, before they start to gain any excess weight that might put them at risk for later obesity," said lead author Maggie Stanislawski, PhD, and research associate at LEAD Center at the University of Colorado School of Public Health.
University of Colorado researchers collaborated with Merete Eggesbø, MD, PhD, who leads the NoMIC study – which began in 2002 – at the Norwegian Institute of Public Health in Oslo, and analyzed data from 165 infants who had BMI measured at 12 years.
One limitation to the study was that the entire cohort was of Norwegian descent, Dr Stanislawski noted.
Researchers compared the BMI at age 12 with gut microbiota samples from six time points throughout the participants’ childhood (at day 4, day 10, one month, four months, one year, and two years). The gut microbiota samples were analyzed using 16s rRNA gene sequencing.
At 12 years of age, 20% of the 165 children in the study cohort were overweight or obese.
"At the early time points, there was somewhat of a relationship between the gut microbiota taxa and later BMI, but the relationship was much stronger as the kids got older," Dr Stanislawski said.
According to Dr Stanislawski, the correlations between the gut microbiota composition and BMI was strongest at one year and two years of age.
“We found this very interesting because, at two years, there wasn't any obvious phenotype in terms of whether or not the kids were going to become obese. Kids who became obese later in life didn't have high BMI scores at age 2.
“The findings suggest that the gut microbiota phenotype was present before any overt sign of overweight or obesity. Since the gut microbiota is influenced by diet, this association could also reflect dietary choices that are precursors to obesity."
The prevalence of childhood obesity was 18.5% among children and adolescents aged 2- to 19-years-old, according to recent data from the CDC.
Study exposes potential health caution
The researchers found that some gut microbes that are generally thought to be healthy in both children and adults were associated with higher childhood BMI especially at high amounts.
While the abundance of Bifidobacterium sp. and Bifidobacterium longum has been thought to promote health in kids and adults, its abundance of these strains resulting from the natural overlap between the maternal and infant gut microbiota in a child’s earliest combined with infant probiotic supplementation may have the opposite effect, Dr Stanislawski said.
“I think a lot of people are giving their infants probiotics. However, it might not be the best idea to give babies the same types of bacteria every day, particularly in very early life when overloading the gut with one or two strains may prevent colonization with other types of important bacteria."
According to Stanislawski, an effective way to improve the gut microbiota of kids is to ensure they eat a well-balanced diet of different types of vegetables and fibers.