A new global study has found that for the first time in history, more people are obese than underweight, and it's only going to get worse.
Almost a fifth of the world's obese adults live in six high-income countries, including New Zealand.
It comes as a group of health experts urge the Government to introduce a tax on sugary drinks.
Chef Adam Newell was a 127-kilogram diabetic when he hit rock bottom four years ago.
"My blood sugars were so high that I ended up with pneumonia and I was in hospital for about 10 days," he says.
Eating and drinking was part of being a chef, but he knew sugar was the enemy, so he quit alcohol and changed his lifestyle, dropping 40kg.
"It is definitely possible if you get in that mind-set that you've got to change your lifestyle," says Mr Newell.
But his success story is not common enough.
Worldwide, obese people now outnumber underweight people for the first time.
"Health professionals have been forecasting this to government for more than 10 years now. We've seen it coming and it's a sad day that we've now crossed that line," says Jeremy Krebs.
A study published in the Lancet medical journal shows the number of obese people has risen from 105 million to more than 600 million in 40 years.
And a fifth of the world's obese adults live in a handful of high-income countries, including New Zealand.
"I think food is absolutely the main issue," says Dr Krebs.
But it's not necessarily the wealthy who weigh more, as countries like Japan and France buck the trend with low obesity rates.
"I think the issue there is the types of diets. Traditional diets eaten in those countries haven't really changed in the way they have in other countries such as New Zealand," says Mr Krebs.
More people here opt for fast food and convenience meals.
Dr Krebs is one of 74 health experts who sent a letter to Cabinet yesterday, urging the Government to follow the UK's lead and introduce a tax on sugary drinks. But Health Minister Jonathan Coleman says it's not something he's considering.
Unless more people can follow Mr Newell's example, experts say one fifth of the world's adults will be obese by 2025.