WW, the rebranded version of Weight Watchers, has launched a controversial weight-loss app aimed at children and adolescents between the ages of eight and 17.
The app, Kurbo, is available for free trial on iOS and Android, encouraging users to track what they eat in a day. The site claims it uses Stanford University-developed "traffic light" system "based on more than 30 years of research".
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Foods are ranked as green ("go foods"), yellow ("eat moderately") and red ("stop and think").
Fruit and vegetables fall under the green label, while lean proteins and pasta are classed as yellow. Burgers, lollies and soft drinks fall under the 'Stop and Think' red banner.
"Numerous scientific studies published in top academic journals have shown that it's safe and effective for weight loss," the Kurbo site says.
Kids, or parents on their behalf, enter their height, weight, age and health goals into Kurbo, which says it's trying to combat rising childhood obesity rates. A New Zealand health survey last year revealed that one in eight Kiwi children are obese.
Success stories on the Kurbo site include 10-year-old Robby, who lost 19kg, and 15-year-old Julinana, who lost 18kg.
WW CEO Mindy Grossman told Time magazine it's all part of their "health mission".
"If we are going to change health trajectories, we have to educate, inspire and support at an earlier point in time," she says.
"There is a very significant need to help families earlier."
But the app has attracted significant backlash. UK surgeon and host of nutrition podcast Dr Joshya Wolrich wrote an Instagram post slamming it.
"Childhood obesity is INCREDIBLY complex. The management is equally as complex, and interventions always involve the family," he wrote.
"In 2016, the American Academy of Pediatrics advised doctors and families to steer clear of weight talk, and instead focus on emphasising healthy lifestyle behaviours.
"This new app laughs in the face of this advice."
Dr Wolrich also pointed out issues of wealth the app raises.
"Obesity (especially in children) is intrinsically tied to socioeconomic class. Who do you think this intervention is going to benefit the most? White middle-class children. Further widening the health inequality that already exists."
According to the NZ Ministry of Health, children living in the most deprived areas of the country are 2.1 times as likely to be obese as children living in the least deprived areas.