More Auckland adults are overwight but the number of overweight and obese pre-schoolers in Auckland has dropped by 2 per cent, according to the latest research from the Healthy Auckland Together coalition.
The monitoring report on the city's obesity rates shows the percentage of obese and overweight 4-year-olds dropped to 20 per cent in 2015 from 22 per cent in the previous year.
On the other hand, the percentage of Aucklanders over 18 who were overweight and obese rose to 61.5 per cent in 2015 compared to 60.7 per cent in 2014.
Almost 80,000 Auckland children were weighed at before school checks in 2015, with the gap in obesity rates closing between Maori, Pacific Island and European/other children.
Despite the drop, the report also showed the effect of too much sugar in children's diets and that many were less physically active.
Coalition spokesperson Dr Michael Hale said looking at what was happening in schools, early childhood education centres and neighbourhoods would help identify why Auckland was seeing this encouraging change.
"We need to find if this trend is a pre-school blip that reverses as children get older," he says.
The research found that fewer 5-14-year-olds were biking or walking to school than in previous years.
"We also know that children are more attached to screens from 7 years onwards, and more exposed to bad food around schools. Without the benefit of more in-depth research, we are just speculating on the reasons at this point.
"Something positive is happening for preschoolers, but not being able to identify the causes makes it difficult to push for change to achieve the same result for older children," Hale said.
Most adults were still not being active enough, or eating the minimum quantities of fruit and vegetables to keep them healthy.
"It is so easy for adults to put on weight, and this is exacerbated by environments that encourage sitting at work, in the car and at leisure, and poor quality snacking and meals."
• A slow rise in adult obesity from 24 per cent in 2007 to 28 per cent in 2015.
•The 43 per cent of all adults meeting the physical activity guidelines hasn't changed over the past year, except for a 4 per cent increase among Pacific Island women.
•There's been a drop in the number of 5-14-year-olds getting to school by bike, scooter, skateboard or on foot.
•The number of missing, filled or decayed teeth in 5-year-olds remains persistently high, with the highest among Pacific Island and then Maori children.