Fast Track to Health (FTTH), which is underway at hospitals in Sydney and Melbourne, puts children as young as 13 on stringent fasting plans for one year.
Participants are at times limited to only one-quarter of their daily recommended energy intake.
Those behind the programs at Sydney's Westmead Children's Hospital and Melbourne's Monash Health believe it will help fight obesity in Australia.
"We are not aware of any studies of young people with obesity that are seeking treatment for their obesity [who] are at an increased risk of the development of eating disorders.
"The people undertaking the study have many years of [experience in the] management of young people with moderate-to-severe obesity and are very aware of concerns that have been raised."
Explore: https://www.abc.net.au/news/2019-03-27/fears-teen-weight-loss-trial-could-cause-mental-harm/10939210