New research predicts an alarming rise of obesity in this country.
A study just out of Otago University suggests two million New Zealanders will be clinically obese in 20 years, up from 1.1 million in 2015.
Dr Ross Wilson told Tim Dower that, at the individual level, Body Mass Index is a rather crude tool, which is going to miss a lot of important aspects of a person's health.
"But at a population average level we know that a high BMI is very strongly associated with a lot of other health problems, so that includes heart disease, diabetes, some types of cancer."
Wilson says BMI is not a perfect measure in itself but captures an important change in people's health.
He says taxes on sugary drinks are controversial but evidence from other countries suggests they do work.
He says improved nutritional labelling should also be considered.
"And encouraging people to be more active is the other big thing that is likely to be important, so whether that''s getting people walking into work, or cycling, rather than just getting in their car and just sitting there."
Wilson says high BMI has now overtaken tobacco as the greatest contributor to health loss in New Zealand.
LISTEN ABOVE AS ROSS WILSON TALKS TO TIM DOWER
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