In the most extreme case, a five year-old with a body mass index of 22.6 was removed from his or her parents by Tameside Council in Greater Manchester after deciding they were doing too little to control the child's weight.
He or she is thought to have weighed around 4st 4lb - a stone and a half more than average.
In another case, a 14-year-old with a BMI of 30.3, giving a weight of 13 stone - five stone more than average - was taken into care by the same local authority.
The removals were uncovered by a Daily Mail investigation following the outrage social workers in Dundee provoked in September by removing four obese children from their parents.
Three girls aged 11, seven and one and a boy of five were placed into care to be 'fostered without contact' or adopted.
Overweight children are at far higher risk of heart disease, strokes, diabetes, asthma and cancer in later life and the most recent NHS figures show that one in ten children starting primary school is obese.
A spokesman for the National Obesity Forum said it supported placing obese children into care, but only after everything possible had been done to try to reduce their weight.
Tameside Council told the Mail: "The point at which obesity turns into a child-protection issue is a complex and difficult area, and in these two cases there were other determining factors that led to the children being placed in local authority care.
"Parents should be supported to address their child's obesity, and social workers should only act if parents fail to engage with the proposed plan to improve their child's safety and wellbeing."
What do you think?
Is obesity a child-protection issue?