A study showing a drop in the number of Auckland pre-schoolers who are obese or overweight, has sparked the interest of primary schools.

The study by Healthy Auckland Together Coalition picked up the trend.

It's bucking the trend of every other age group, who are getting fatter.

Early Childhood chief executive Peter Reynolds told Mike Hosking it's a result of play-based learning at childcare facilities.

"We're finding more and more primary schools are starting to sit up and take real close notice of what's going on in early childhood education.

"They're looking at the curriculum, they're looking at things like play-based learning and saying 'hey that could actually work for us, especially for the new entrant children."

"So it doesn't surprise me with the growing involvement in early childhood education that kiddies are moving more, and that as a result, those who need to lose a little bit of weight as a result of that sort of movement and development are doing so."

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