A South Auckland woman who lost 50kg for her health's sake says saturating deprived areas with fatty-food outlets is killing children.
Every year about 1200 cancer cases in New Zealand are attributed to the patient being overweight or obese - and health experts say that can be prevented.
Leitu Tufuga said in her neighbourhood, in Mangere, healthy food options were limited and growing up to be overweight was almost a given.
"In my neighbourhood a pie and Coke for breakfast is the norm.
"I am scared for my nieces and nephews - they are surrounded by rubbish food everywhere they look. I don't want them to end up where I was eight years ago."
At that time, Tufuga weighed 137kg, she had just been diagnosed with type 2 diabetes and was confronted with the reality that if she wanted to keep living, her fast-food lifestyle had to end.
Little did she know obesity was also a major contributor to cancer.
Cancer Society medical director Chris Jackson said obesity in New Zealand was a growing epidemic and a major contributor to cancer.
"We need to double down on prevention - obesity is a disease we have some control of and social policies can have a huge impact."
Tufuga, now 50kg lighter and committed to a healthy lifestyle, said changing her eating habits was difficult because good, healthy food was harder to find in her neighbourhood.
"There are takeaway joints everywhere you look, and barely any fresh fruit and vege shops.
"Even in the supermarket there's loads of processed and calorie-rich food everywhere and it makes it harder to buy healthy."
She said she had given up trying dozens of times and knew many people faced the same battle.
"I was shocked to learn obesity was a risk factor of cancer because back then I was the perfect statistic."
She said she was worried for families.
"Our environment just isn't healthy and the negative impact on our health is huge," she said.
Australian public health researcher Anna Peeters, who is speaking in Auckland today as part of the Cancer Research Week, said the direct link between cancer and obesity was something many weren't aware of.
The greater number of cells in excess body weight meant a higher likelihood of getting cancerous cells.
Obesity was not a contributing factor for all cancers but there was strong evidence that greater body mass was "a cause of oesophagus, pancreas, liver, colorectum, breast and kidney".
Peeters, a member of the policy advisory group for the World Cancer Research Fund, said there were many practices and polices governments could implement to improve the food retail environment.
"Robust obesity plans that involve all departments and engage multi sectors across population need to be introduced and monitored by government.
"A sugar tax is the easiest one to implement and really robust regulation around marketing unhealthy food and drink to children has also proven to have huge impacts."
She said there was a lot New Zealand could learn from polices introduced overseas.
The Cancer Society's Cancer Research Week for 2018 is focused on prevention, in particular the "big three" risk factors of obesity, alcohol and tobacco.
The society is urging the Government to introduce policies which help to reduce the sale, supply and availability of fast foods, sugary drinks, alcohol and tobacco.
About Cancer Prevention:
• More than 30 per cent of cancer cases are potentially avoidable in New Zealand.
• Lung cancer, bowel cancer, breast cancer and melanoma skin cancer are the four most common preventable types of cancer.
• Obesity is the single biggest preventable cause of cancer after tobacco.
• Obesity is responsible for about 1200 cases of cancer in New Zealand each year.
• Alcohol is responsible for about 240 cancer deaths each year in New Zealand.
• Smoking and second-hand smoke is responsible for about 5000 deaths in New Zealand every year.
• Cancer is estimated to cost the New Zealand public health system more than $800 million a year.