A new study has found family income, education and neighbourhoods are major drivers of different obesity rates between Māori and pākehā children.
Higher obesity rates among Māori four-year-olds would be halved if they were brought up in better circumstances, and brought down by a third for Pasifika children the same age.
University of Auckland researcher Barry Milne, who leads the University of Auckland COMPASS unit which conducted the research, says neighbourhoods are one factor.
"You may live in an area that's poor that doesn't have good access to fresh fruit and vegetables, but it does have good access to fast food."
Public transport and green spaces for activity also play a part.
"Even if we can't change the poverty circumstances in those environments, at least have healthy options... well-served by green space and the ability to walk places easily."
The study looked at data from 250,000 four-year-olds. Eleven percent of pākehā were obese, 20 percent of Māori and 33 percent of Pasifika. Family and neighbourhood conditions accounted for about half the difference between Māori and pākehā obesity rates.
Study lead author Nichola Shackleton told NZME New Zealand's colonial history is partly to blame.
"Power and resources were taken from Māori, who were marginalised by new social systems based on European norms and values.
"Increased health needs among Māori and their increased experience of deprivation may be a consequence of the repression of indigenous peoples, the confiscation of land and political power, and the breaching of their rights."
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Dr Milne says the Government's focus on poverty and wellbeing is a start towards fixing it.
The study was published in the International Journal of Obesity on Friday.