Could daycare be putting your preschooler at risk for obesity? A new study of Quebec children has found that kids who attended centre-based daycare were 1.65 times more likely than children in parental care to be overweight or obese between the ages of 4 and 10.
Lead researcher Dr. Marie-Claude Geoffroy says the findings can't be interpreted as showing causality between daycare and obesity, but they do suggest something may be going on there that contributes.
"We don't know why, but two possibilities are nutrition and physical activity, because they are key contributors to [becoming] overweight," says Geoffroy, adding that there could also be other factors her study didn't measure.
Researchers followed 1,649 families with children who were born in 1997 or 1998, from a data sample that is considered representative of the majority of Quebec kids. From 1.5 to 4 years of age, their mothers were asked about the kind of care the children had – and they were classified according to which they spent the most time in. Thirty per cent were in a centre-based daycare, 35 per cent in a family or home-based daycare, 11 per cent with an extended family member, 5 per cent with a nanny and 19 per cent with their parents.
The children's weight and height measurements were taken over the subsequent six years and, applying widely used international standards that rely on body mass index (BMI) adjusted for age and gender, the overweight and obese children from within the group were identified.
In addition to the daycare finding, the study also found a link (albeit less statistically certain, according to researchers) between care by a relative, such as a grandparent, and a 1.5 times greater chance of being overweight or obese. The researchers controlled for other factors linked to obesity, including socioeconomic status and duration of breastfeeding.
Geoffroy says she was initially surprised by the findings because her previous research had highlighted the positive benefits of daycare, especially on cognitive measures. "I was expecting child care to be a good way to prevent [obesity]," she says, adding that she's found a few other studies with similar conclusions.
She hopes parents don't interpret her findings as a knock against daycare. Geoffroy, a research associate at University College London affiliated with the Université de Montréal at the time of conducting the study, says more research needs to be done to both clarify the link between daycare and obesity – and suggest potential solutions.
"I don't want parents to be worried, but they should just try to be sure their child is eating well and is doing enough exercise – at home and at daycare," she says.