A child sits on a gym floor. / John Moore/Getty Images

Parents who struck a balance between being strict and kind were less likely to bring up obese children

Strict parents who offer more stern words than affection are at risk of making their children obese, researchers have claimed.

The obesity epidemic affecting countries across the world, including the UK, could be lessened if parents and children had better relationships, according to the study presented at an American Heart Association conference.

Lisa Kakinami, a researcher from McGill University in Montreal, Canada, where the paper was based, said: “Parents should at least be aware of their parenting style.

“If you’re treating your child with a balance of affection and limits - these are the kids who are least likely to be obese.”

To make their findings, the Canadian researchers looked at a population of 37,577 children aged 11 and younger, and compared parents' answers to a cross-sectional survey. Scientists then categorised parenting styles, and matched them to children's body mass index (BMI).

BMI is a measurement that relates height and weight and is often used to define overweight and obesity thresholds.

Children of the comparatively authoritarian group who imposed strict rules and showed little affection, had a 30 per cent higher chance of being obese at age two to five, and a 37 per cent higher chance at age six to 11.

While poverty was also associated with childhood obesity, overall parenting methods had a greater impact on a child’s BMI, the scientists found.

Cynthia Davis, of the Harvard Medical School, told The Times: “This dovetails nicely with our work that demonstrates links between childhood adversity and obesity.” She and her colleagues look at more extreme problems in childhood, such as abuse, alcoholic parents and domestic violence.

"They believe that they have uncovered biological changes that explain the correlation.

“Two recent studies of ours have shown that this type of severe and chronic adversity in childhood is associated with metabolic disregulation at the biochemical level and central obesity in midlife, regardless of lifestyle factors, such as diet and exercise and psychosocial factors like depression and social support,” she said.

Stephen Daniels, from the American Heart Association, where the research was presented, told the newspaper that the work offered practical guidance for parents. “This really does provide a framework for parents to think how they should approach children, and how that will affect the child’s overall risk of obesity.”

Additional reporting by PA