New Zealand 4-year-olds buck obesity trend

New Zealand’s four-year-olds are resisting the tide towards rising obesity, according to research funded by A Better Start, one of the country’s national science challenges.

By analysing national data from the B4 School Check, a health check conducted each year on the country’s four-year-olds, researchers have found that there has been a 2.2% decline in the number of youngsters who are overweight, obese or extremely obese between 2010 and 2016. The decline is across the board, across gender, ethnicity, socioeconomic status and urban and rural children.

Lead author Dr Nichola Shackleton of the University of Auckland said, “The research has found a small decline in what has been a rising tide of obesity in our children. While that’s good news for 4-year-olds, we don’t know if this effect continues once they reach school.”

The decline needs to be seen in the context of our rates of childhood obesity which remain among the highest in the world.

The research is a collaboration between the Challenge Healthy Weight and Big Data research teams at Auckland, Otago, Massey universities in New Zealand and Uppsala University in Sweden. Over the six years, the B4 School Check was completed by registered nurses on between 75% and 92% of four-year olds, about 317,000 children.

Reducing childhood obesity, is fundamental to ensuring better health outcomes for children. Obesity is linked to a long list of health conditions, including heart disease, type 2 diabetes and some forms of cancer. Obesity contributes to about 9% of all illness, disability and premature death. A Better Start Director Professor Wayne Cutfield said,” This adds to the picture we have on child obesity. It’s a priority research theme for the Challenge because not having a healthy weight is a leading factor preventing children from going on to lead healthy and successful lives.”

Challenge co-director Professor Barry Taylor, the Dean of the Dunedin Medical School at Otago University, said the research showed the power of the Integrated Data Infrastructure, the project to bring publicly gathered data together for research. “By matching the B4 School Check data with Census information, it has been possible to generate community level information that can be shared to lift the health of their neighbourhoods,” he said.

The current main source of data on childhood obesity comes from the National Health Survey, which relies on data from fewer than 5000 children, between 0 and 14 years.

Professor Cutfield said the decline might indicate that health promotion is working on families with young children. For young children, families have easier access to physical activities and better control on what they eat.

This is the first of 11 studies planned for the next two years by the A Better Start Healthy Weight and Big Data teams that will examine important associations between early life events and childhood obesity. These include being born early (preterm), late (post-term), too small (small for gestational age), too large (large for gestational age), increased maternal age, maternal antibiotics in pregnancy and frequent antibiotic exposure in early childhood.

The research is published in the journal Paediatric Obesity.

Fact box:

• A Better Start is one of 11 National Science Challenges representing a strategic investment in science to respond to complex issues facing New Zealand.
• A Better Start has three priority research areas: Healthy Weight, Successful Learning and Resilient Teens, with a cross-Challenge research programme run by Big Data specialists.
• The National Health Survey estimates that 33% of children of between 4 and 5 year olds are overweight or obese.  This rises to >40% for Maori, >50% for Pasifika and >40% for children in low socioeconomic areas
• ·For OECD countries New Zealand ranks 4^th out of 34 countries for children between 2 and 19 years who are overweight and obese, immediately behind the United States.
• The OECD country with the biggest child obesity problem is Chile, 31.6% of boys and 37% of girls.
• Improving rates of obesity in New Zealand 4-year-old children is a paper authored by: Nichola Shackleton, Barry Milne, Rick Audas, Jose Derraik, Tong Zhu, Rachael Taylor, Susan Morton, Marewa Glover, Wayne Cutfield and Barry Taylor.

Listen to Co-Director Professor Barry Taylor’s interview about the research on RNZ.