"New Zealand is in the grip of a global obesity epidemic, the future costs of which will be enormous, potentially unaffordable for the health system."
Obesity is a risk factor for diabetes and cardiovascular disease.
Otago University professor of human nutrition and medicine Jim Mann told the Science Media Centre the obesity figures were alarming, but not surprising.
"We need an overarching strategy to deal with obesity and the prevention of diabetes ... we used to have a strategy - Healthy Eating, Healthy Action - but it wasn't in place long enough to find out if it was working."
Parts of it were still in place, such as fruit in low-decile schools, but that was only "a tiny start towards creating an environment to encourage healthy food choices and physical activity choices".
Other findings in the report include:
6.9 per cent of adults had diabetes, based on blood tests done for the survey, compared with 3.7 per cent who reported having been diagnosed with the disease in the 1996-97 health survey.
The reported energy intake of adults has declined since 1997, a finding that led one expert yesterday to suggest that people had probably under-reported their consumption in the new survey.
7.3 per cent of adults live with low levels of food security, up from 2.7 per cent in 1997.
Health Minister Tony Ryall said that although state spending on healthy-eating programmes had decreased under National, more was going into physical activity programmes.
"The Government is concerned about the level of unhealthy weights in the community. While the Government can do things to help, there are elements of personal responsibility here." It was something that had to be done in partnership between individuals, families and the community.
Bigger, bigger
* 1977 - 10 per cent of adults obese, 34 per cent overweight.
* 1997 - 17 per cent obese, 35 per cent overweight.
* 2008-09 - 28 per cent obese, 37 per cent overweight.
Source: Ministry of Health.
