Lack of exercise, $1.50 pies, an abundance of fried chicken and traditional Polynesian food served with lashings of coconut cream have resulted in an obesity rate in Pacific adults of more than 60 per cent.
Twenty-eight per cent of New Zealanders aged 15 and over - "about one million adults" - are obese, the 2013 Ministry of Health annual report says.
The report stated excess weight was a leading contributor to a number of health conditions including type 2 diabetes, ischaemic heart disease, stroke and several types of cancer.
Obesity rates were higher among Pacific adults (62 per cent) and Maori adults (44 per cent), and Pacific children (23 per cent) and Maori children (17 per cent).
South Auckland had the largest number of obese residents, and Otara Health community development leader Maddi Schmidt said a lack of healthy options was a factor.
About 70 to 80 per cent of the suburb's population was overweight, she said. In the Otara town centre, the only healthy options were a sushi store and a cafe run by the local Manukau Institute of Technology.
"We've been wanting Subway for many, many years, but business-wise they didn't think it was feasible."
The town's residents had a poor diet, which was not helped by an abundance of traditional coconut cream-heavy foods, Ms Schmidt said.
"Eating here for the kids is still really, really bad."
Local children would rather have a steak and cheese pie or two in the morning, which sold for a mere $1.50 each, rather than have cereal at home for breakfast, she said.
It was hard to promote healthier options when the area offered such an abundance of fried foods: "Every single bakery in this town centre sells fried chicken."
She said the local health centre worked to identify alternatives by offering residents a walking tour through the centre, identifying healthier options such as boiled taro, sweet corn soup and stir-fries.
The key to the programmes' success was making them enjoyable, Ms Schmidt said. "At the moment we've had a month of Tongan aerobics ... If you can get them laughing, you can get them coming back."
Capital and Coast DHB's director of Pacific health, Taima Fagaloa, said the core of the problem was what people were eating, and how little they exercised.
Porirua had the second-largest Pacific population in the country, however local businesses and the health sector needed to work together to improve the availability of healthy food, like affordable fresh vegetables, she said.
Consistent messages about good diet and exercise needed to be conveyed in languages other than English, for Pacific language speakers, Ms Fagaloa said.
Porirua Mayor Nick Leggett, who had a stomach-stapling operation to lose weight, said convenience foods had become more common and people were not exercising as much as they could.
"But unfortunately, at the end of the day it is about the individual and [excess weight] is a very, very difficult thing to reverse. It's hard work."
The Ministry of Health report defined obesity as a body mass index (BMI) of 30 or more, calculated by dividing a person's weight in kilograms by the square of their height in metres.
With a BMI of 32, All Black Ma'a Nonu is technically obese, as is Richie McCaw (BMI of 30).
League star steps up for kids
Former professional league player Monty Betham said he was prompted to set up his Steps for Life programme - working with at-risk children to turn the tide of obesity - when he read that New Zealand ranked third in the OECD for obesity.
"When I came across that article after leaving professional sport and helping professionals do personal training and helping people lose weight, I realised that I'm helping the wrong people.
"I've got to be helping our kids, I've got to be helping the people that don't necessarily have the money to do so or the know-how."
Betham said New Zealand's obesity problem stemmed in-part from cultural protocols and being raised without knowing any different.
"A lot of our ethnic groups, particularly the Islanders, have got cultures where they work hard and show their love through food.
"Every Sunday they have meetings and that's where everyone gets together and they celebrate. It's disrespectful if you don't have another helping or third helping, and that's the way it works."