A traditional Maori staple - eel - may hold the answer to stemming the growing tide of obesity-related type-2 diabetes.
The prevalence of obesity-linked diabetes has rocketed ahead of predictions, leading to dire forecasts about its expected toll on health services and the quality of life of a substantial proportion of people.
But health researcher Marie Benton believes a simple intervention incorporating the omega-3 fatty acid found in high quantities in eel could prevent many from developing the disease.
Eel, smoked or in stews, has long been the traditional staple of Mrs Benton's Waikato Tainui hapu.
With their support, she embarked on a 10-year study comparing those who ate eel regularly and still lived a largely traditional lifestyle with those who lived on a more Western diet high in saturated fats.
Of the nine in the first group, none had developed type-2 diabetes. All are still alive and healthy, with two in their 80s.
But everyone in the second group developed diabetes. Seven have died, most in their 50s and 60s. Only two survive, aged 42 and 50.
She also interviewed more than 60 people in her hapu. Even among siblings, those who moved towards a more Western diet and lifestyle were more likely to develop type-2 diabetes.
Mrs Benton believes the almost daily consumption of eel was an important factor. The study formed part of her Massey University doctorate, which explores the sudden explosion of type-2 diabetes in Maori after the 1960s. Previously, the condition was unheard of in Maori - a notion borne out by medical literature.
Maori urbanisation in the 1950s is thought to have played a major role in the rapid growth of diabetes, as did the diminished supply of eel in parts of the country with hydroelectric dam projects.
In 1996, she proposed the theory that the omega-3 found in eel acted as a protectant against type-2 diabetes.
"People laughed at me."
Little was known about omega-3 then, although studies have now shown it to be beneficial against a number of conditions, including heart disease, anxiety and depression, and inflammatory conditions such as arthritis.
Auckland oils and fats specialist Dr Laurence Eyres said it was quite possible that omega-3 was beneficial against diabetes, too. Modern Western-based diets were typically low in omega-3.
Mrs Benton had the long-finned eels, traditionally consumed, chemically analysed. Even after storage and smoking, the fish were found to contain high levels of omega-3 - levels far higher than salmon and on a par with sardines.
Mrs Benton said the regular consumption of eels, and the lifestyle that evolved around eel catching, storage and preparation, was a big factor in why type-2 diabetes did not develop in Maori.
Type-2 diabetes could be prevented, but she stressed that the consumption of omega-3 must also be accompanied by a healthy lifestyle which included regular exercise and a diet rich in fruit and vegetables.