A person is considered obese when his or her weight is 20 per cent or more above normal weight. Obesity rates have nearly tripled in recent decades. In 1977, only 9 per cent of males and 11 per cent of females were obese.
"Our messages are to eat plenty of fruit and vegetables, choosing low fat milk, reducing salt ... and cutting down on portion sizes," Mrs Mahy-Willis said.
People should also try to cook their own food and watch what they nibble on, as many snack foods were high in fat and sugar, she added. Diabetes New Zealand was not surprised by the Obesity Society award.
"The worst thing [the Government] did ... was they abandoned the rule that had been implemented ... that demanded school tuckshops and canteens only had available healthy food for sale," president Chris Baty said.
"It's not just a matter of an individual eating too much and not being active enough.
"It's actually a societal problem."
Obesity rates for children aged 2-14 years show one in 12 are obese and one in five are overweight.
Mrs Baty said obesity was often a significant contributing factor in type two diabetes, which is a disease the Ministry of Health estimates affects more than 200,000 New Zealanders. "There's a massive increase in diabetes," she said.
"It certainly is linked with the increase in obesity but it's not the only reason."
