Two-thirds of Kiwis overweight - study

New Zealand has the highest rate of obesity in Australasia, according to a new global analysis.

The number of Kiwis classed as overweight or obese has risen dramatically since 1980, hitting 66 per cent, the study of trend data from 188 countries found - up from 50 per cent 33 years ago.  

Childhood obesity rates have also increased, rising to 29 per cent from 18 per cent in the same period.

The research, published in medical journal The Lancet, was conducted by an international consortium of researchers led by the Institute for Health Metrics and Evaluation (IHME) at the University of Washington. The study is part of the wide-ranging Global Burden of Disease project.

It found an estimated 2.2 million adults in New Zealand are overweight, and of those 960,000 are obese. Within the Australasia region, New Zealand has the highest rate of obesity in both adults (29 per cent) and children (9 per cent).

More women than men are obese, with 510,000 women falling into that category compared to 450,000 men.

Half of all overweight women in New Zealand are obese. Obesity rates for women aged 20 or older reached 30 per cent, more than triple the obesity rates among girls (9 per cent).

Obesity rates among boys climbed from about 10 per cent in childhood and adolescence to almost 28 per cent in adulthood.

"Being overweight is a well-established risk factor for stroke, heart attack, dementia and cancer - the four major causes of death and disability in New Zealand. Therefore, the fact that New Zealand has the highest rates of adult and child obesity in the region is very alarming," Professor Valery Feigin, from AUT University who co-authored the report, said.

"If this obesity epidemic is not stopped, we will suffer an increase in the burden of these most devastating disorders.

" Urgent action was needed at both government and individual levels, he said.

When looking at obesity alone, Australasia experienced the largest absolute increase in adult obesity since 1980 (from 16 per cent to 29 per cent) and the single largest increase in adult female obesity (from 17 per cent to 30 per cent) globally.

"Obesity is an issue affecting people of all ages and incomes, everywhere," said Dr Christopher Murray, director of IHME and a co-founder of the Global Burden of Disease (GBD) study.

"In the last three decades, not one country has achieved success in reducing obesity rates, and we expect obesity to rise steadily as incomes rise in low and middle-income countries in particular, unless urgent steps are taken to address this public health crisis."

The study found that obesity rates in developed countries had slowed since 2006, but in developing countries -- where almost two-thirds of the world's obese people live -- increases looked likely to continue.

Key global findings:

- 2.1 billion people - nearly one-third of the world's population - are overweight or obese. The number of overweight and obese individuals in the world has increased from 857 million (20 per cent) in 1980, to 2.1 billion (30 per cent) in 2013.

- In high-income countries, some of the largest increases in adult obesity have been in the US (where one-third of adults are obese), Australia (where nearly 30 per cent of men and women are obese), and the UK (where around a quarter of the adult population is obese).

- More than 50 per cent of the world's 671 million obese live in 10 countries (ranked beginning with the countries with the most obese people): US, China, India, Russia, Brazil, Mexico, Egypt, Germany, Pakistan, and Indonesia.

- The highest proportion of the world's obese people (13 per cent) live in the US.

- Patrice Dougan of APNZ