A new study showing Māori and Pacific babies in New Zealand are leaner than other ethnic groups could help refocus early healthcare.
The first study of the body composition of the country's newborns revealed Māori and Pacific babies were more lean than their Pākehā and Asian counterparts.
Researchers from the Auckland-based Liggins Institute used a special air displacement machine combined with tape measurements and scales to determine the mass of 440 babies born in the city between May 2015 and April 2018.
Babies were classified as either Māori and Pacific, Pākehā or Asian.
While Māori and Pacific babies were longer, had larger heads and were heavier than others, their extra weight was found to come from fat-free mass like bones, muscles and organs.
Lead researcher Tanith Alexander, who is also a dietician at Middlemore Hospital, said the study brought follow-up questions as although the newborns were leaner, Māori and Pacific children soon became some of the most obese.
"That's actually the highest [group], so to me, what's happening between the time they are born and childhood, that they switch from being the leanest to having the most amount of fat basically," she said.
"What's happening in there? Is it environmental factors that are affecting that and what can we do about it?"
Ms Alexander hoped the findings would prompt more research.
"It might lead to some more interesting research on what we can do long-term to measure body composition.
"Is there a certain time when the body composition is flipping over to be higher in fat mass and how can we intervene earlier and I think early intervention is probably the key."
The research team said the findings once again highlighted the importance of health promotion from the earliest years to set children up for life-long health.
Proposed actions included supporting mothers to breastfeed, guidance around introduction of solids, community-based promotion of healthy eating and exercise for children and whānau, and regulatory or pricing changes to make healthy food cheaper and more accessible.