Schools are being encouraged to cut out sugary drinks.
The Ministry of Health says a simple water-only policy is the way to go.
Its chief advisor on child health, Pat Tuohy, says sugary drinks can cause tooth decay and contribute to childhood obesity.
"According to the latest health survey results, one in nine children in New Zealand is obese and a further two are overweight," he said.
"The World Health Organization recommends schools create healthy food environments, so introducing a water only policy is a great first step for schools."