Childhood obesity may not cause 'lifelong risk'

Young children may gain weight early due to their genetics, and this does not mean they face a lifelong risk of obesity, researchers say.

Analysing 6,291 kids from the University of Bristol's Children of the 90s study, experts from Australia used modelling to explore how genetics contributes to differences in how children's body weight changes from ages one to 18.

The results suggested body size differences in younger children did not mean a child would be overweight in the future.

Dr Geng Wang, from the University of Queensland, said: "Parents often worry when a child gains weight early or grows differently from others, but our findings suggest that genetic variation can influence these changes."

"We found genetic factors that contribute to an infant's body size may be different from the ones contributing to a teenager's body size," Wang added.

"When using these results to consider health, our results suggested body size differences in younger children don't necessarily reflect lifelong obesity risk."

The study, published in online journal Nature Communications, found the BMI of older children, around the age of 10, as well as the overall growth rate from one to 18 years, is more likely linked to diabetes, high cholesterol and heart disease later in life.

Professor Nicholas Timpson, principal investigator at Children of the 90s, said the work suggested "important genetic relationships with the way BMI changes from one to 18 years old, as well as average levels at any given age".

"The results here really do help us to get a better feel for the changing patterns and implications of health-related factors – like body size – as they vary across the life course," he added.

Dr Nicole Warrington, also from the University of Queensland, said: "Future research is needed to help identify the most effective ages to prevent obesity or poor growth for long-term benefit."

Data from 2024/2025, from the National Child Measurement Programme, showed boys were more likely to be overweight than girls, with 10.5% of children in Reception, aged four to five, and more than a fifth in Year 6, aged 10 to 11, as being obese.

Excluding the peak during the first year of the pandemic, this is the highest obesity prevalence seen in Reception Year since records began in 2006/07, and is higher than the 9.6% in 2023/24.

The Bristol-based Children of the 90s project began by tracking 14,500 children born in between 1991 and 1992.

It is the most detailed project of its kind in the world and has led to discoveries in all aspects of health and wellbeing from eczema, bodyweight and cancer.

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