The restaurateur would show them how to cook and shop for healthy foods and experts in exercise and meditation would help the contestants change their lifestyles.
"The idea is to get people off medication, introduce them to a new way of life and show them how to manage their condition," Gault said.
"This will be the MasterChef that makes a difference."
Gault, who has just left the Nourish Group, owner of nine of the country's most popular restaurants including Euro, became passionate about the subject after being diagnosed with Type 2 diabetes. He attended a holistic treatment centre in the UK last year after being advised by specialists to lose weight. He was prescribed medication.
"I wanted to do something about it quickly as I have a young daughter and I want to be around to see her walk down the aisle," he said. "I consulted Dr Google and found a place in Britain that helped me change the way I live and eat.
"Not everyone can afford to do that, so through the TV series I want to highlight a serious problem, get people thinking about diabetes and what to look for.
"It is difficult to change your lifestyle. I work hard to keep my weight down and avoid too much stress. I was so close to going on insulin.
"Yet there are people out there still getting their feet and legs amputated because they have diabetes. It is a condition that requires life-changing decisions to manage."
NZ On Air chief executive Jane Wrightson said the show was a good proposal. "Unfortunately, we have been oversubscribed with applications for funding for health and obesity-related programmes and have three in production. It is a popular topic and the applicants are welcome to try again for funding next year."
Gault is now seeking other investors. "This is too important an issue to wait another 12 months."
Diabetes is the largest and fastest growing health issue facing New Zealand.
It is closely linked with heart disease and together they are responsible for the deaths of more New Zealanders each year than cigarettes.
Chris Baty, president of Diabetes New Zealand, believed the lack of funding was an opportunity lost to reach a large audience.