Overweight and obese children drink a median of one glass of fizzy or other sweetened drink per day, say researchers who are battling deeply-ingrained bad eating habits.
But while the median intake of sweet drinks, including cordial, powdered drinks, fruit juice and energy drinks, was 250ml in the study, some drank none - and others up to 2 litres a day.
The Maori children's median was double the Pakeha figure in the study of overweight and obese children aged 4 to 16 who are enrolled in a Sport Taranaki programme to help families make healthy lifestyle changes.
"The volume of sweet drink is a concern because that's extra energy," said Taranaki District Health Board paediatrician Dr Yvonne Anderson, one of the authors of the study, done with colleagues from Auckland University and its Liggins Institute.
"One can of sweet drink contains three days' worth of the recommended added sugar for young children."
A 250ml sweet drink could equate to an extra 100 kilocalories a day of added sugar.
"It's been estimated that extra energy intake of not much more than that - 120kcal a day - leads to a 50kg increase in body weight over 10 years," Anderson said.
She favours introducing a tax on sugar-sweetened drinks - a policy the Government has refused to entertain - as it would help to make the healthy choice the easy choice, but she said it would be only part of the solution.
"We often have to break the habits of generations."
She cited a grandmother in the Sport Taranaki programme who always had a cupboard full of lemonade for her grandchildren.
"We all work together and now she gives time for the children rather than providing lemonade and there's always unflavoured milk and water for the children. She's worked out other ways to reward and love her grandchildren rather than lemonade."
The children in the study were found to eat takeaways on average 1.3 times a week, compared with once a week for the mainly non-obese children in a national health survey.
Sixty-seven per cent in the study experienced excessive hunger and ate large amounts of food, and 51 per cent didn't feel full after a meal.
The Sport Taranaki programme is the kind of scheme the Government wants obese children referred to under its new Raising Healthy Kids target.
The Herald revealed this week that nearly 20 per cent of families are declining such referrals in central, north and west Auckland. One expert suggested this may be because they didn't want their children stigmatised.
Anderson said 78 per cent of families referred to the Taranaki programme became "engaged" with it.
"We don't even use the word 'obesity'. It's about making healthy choices in the whole whanau. As a child, you can't do that on your own."
"The sorts of changes we are seeing are from families with lots of children who eat takeaways four or five times a week with the telly on in their living room.
"They have come to us and engaged with us. Now they are down to only one takeaway every one to two weeks - takeaways are part of a busy family's lives - however, now they eat takeaways at the park and do sporting activity around that."
• 239 overweight or obese Taranaki children aged 5-17
• 67% experienced excessive hunger and ate larger amounts of food
• 51% did not feel full after eating
• 9% woke in the night and asked for food
• 62% reported comfort eating
• 3.5 servings of fruit and vegetables was the average eaten per day
• 5.6 was the average number of days per week on which breakfast was eaten
• 250ml was the median daily intake of sweetened drinks
Source: PLOS ONE scientific journal