This article is more than 5 years old. Information may no longer be current.
Age-based environmental factors may influence childhood obesity
Click Here to Manage Email Alerts
Contemporary children in certain populations are exposed to two distinct environmental pressures that put them at risk for obesity — one while very young and another encountered during puberty — that were not a concern for children born a generation ago, according to research in the International Journal of Obesity.
In a 12-year longitudinal cohort study that compared contemporary British children with children born 25 years ago, researchers found that contemporary children at age 5 years have a higher BMI than children born 25 years ago and that the disparity only increases as current children reach puberty. Parental behavior likely influences early weight gain, whereas increasing freedom of food choice in puberty may influence weight gain in older children, according to researchers.
“The results are straightforward but novel, and suggest that the obesogenic pressures to which modern children are exposed differ not only from those of a generation ago, but according to the stage of childhood as well,” the researchers wrote.
Mohammod Mostazir, MD, of the department of endocrinology and metabolism, Plymouth University Peninsula School of Medicine and Dentistry, U.K., and colleagues at other institutions analyzed data from 307 children (55% boys; 98% white) who were measured annually from age 5 to 16 years (2000 to 2012) as part of the EarlyBird study, which monitored their height and BMI. Researchers compared those findings with a BMI data set used to construct the U.K. 1990 growth chart centiles. Researchers used group-based trajectory modeling (GMTM) to establish whether categorical trajectories emerged.
There was no difference in birth weight between the EarlyBird cohort and the children from 1990, but by age 5 years, EarlyBird boys and girls had a greater BMI, with 4% of boys obese (95% CI, 1-7) and 5% of girls obese (95% CI, 1-9), according to researchers.
Both sexes in the EarlyBird cohort gained excess weight year-by-year throughout childhood so that, by 16 years, 11% of EarlyBird boys and 16% of EarlyBird girls were considered obese.
Exaggerated skew accounted for the difference early on, whereas widening variance accounted for it later, according to researchers.
“The mean BMI of the EarlyBird children was higher than that of the 1990 standards throughout the course of childhood, but for reasons that changed as the children grew,” the researchers wrote. “The sequence of events points to trends in the distribution of BMI over the course of contemporary childhood that are different from a generation ago, when skew and variance were more relatively stable.”
Researchers attributed the higher BMI in young children to parental behavior, as many of the parents of children with overweight were themselves overweight or obese. The difference in BMI among older children was attributed to a more general environmental exposure.
The results suggest a two-pronged approach may be needed to better address obesity and overweight in children, according to researchers.
“Two quite distinct strategies may be needed to reduce obesity in today’s children — the one aimed at parental conduct during the early years (or even preconception if epigenetic change proves to be important), the other at the wider environment later on,” the researchers wrote. – by Regina Schaffer
Disclosure: The researchers report no relevant financial disclosures.
Click Here to Manage Email Alerts