Strict parents who show little affection could be more likely to have obese children.

New research suggests parents who are "demanding but not emotionally responsive" are one-third more likely to have obese children, an American Heart Association news release reported. 

A research team looked at 37,577 Canadian children between the ages of zero and 11; they compared children who had generally affectionate but authoritative parents who had "reasonable discussions about their behavior" with those that had authoritarian parents who did not show as much affection. 

Children between the ages of two and five who had authoritarian parents were 30 percent more likely to be obese, that number jumped to 37 percent in the six to 11 age range. 

"Parents should at least be aware of their parenting style," Lisa Kakinami, Ph.D., a post-doctoral epidemiologist at McGill University in Montreal, said in the news release. "If you're treating your child with a balance of affection and limits - these are the kids who are least likely to be obese."

The researchers reviewed the answers parents had given on a cross-sectional survey about their parenting styles; they then compared these results with a measure of the children's body mass index (BMI) percentile. 

"The main difference in authoritative vs. authoritarian styles is the warmth expressed between the parent and child," Kakinami told Time. "Authoritative parents ranked higher on praise than authoritarian parents." And when their children misbehaved, authoritarian parents were "most likely to respond emotionally and punish the child but not tell them what they had done wrong."

The team also found a link between childhood obesity and poverty, but parenting style was a significant factor regardless of income, the news release reported. 

"More than one-third of American children are overweight or obese according to the American Heart Association. Exploring factors at home that may be fueling this public health concern could lead to better prevention and interventions," according to Kakinami, the news release reported. 

The study was co-authored by Tracie Barnett, Ph.D., and Gilles Paradis, M.D.