12 Jun 2017

Call for BMI scale to be customised for different ethnicities

From Jesse Mulligan, 1–4pm, 1:25 pm on 12 June 2017
Associate professor Scott Duncan wants Kiwi-specific BMI scales.

Associate professor Scott Duncan wants Kiwi-specific BMI scales. Photo: 123RF

Associate professor Scott Duncan is the head of research of AUT's school of sport and recreation. He has just completed a study of 1676 adolescent girls and is concerned at the findings based on using a universal BMI calculation.

The study, published in the New Zealand Medical Journal, found that in participants of the same weight and height, South Asian individuals had on average six per cent higher body fat than Pacific Island individuals.

Dr Duncan says some people are being unfairly called obese when their weight is due to muscle mass and others who have high levels of body fat are not being classified as at risk because of their overall weight, and the BMI scale needs to be customised to each ethnic group.

For example, he says Maori and Pacific island people are often over-classified as overweight according to current BMI standards,

"They're heavier in general; they have more lean muscle mass, as well as having bigger frames. And the opposite goes for Asian and Indian populations, who tend to be under-classified as overweight."