A third of year six children in England are now obese or overweight, new research has revealed.
Data management experts SSentif analysed statistics from the Information Centre for Health and Social Care and The National Child Measurement Programme ranging from 2006/07 to 2010/11.
Since 2007, 80 per cent of primary care trusts (PCTs) in England have reported an increase in obesity rates at age ten to eleven, while 36 per cent have reported an increase in four to five year-olds.
According to the study, Southwark PCT had the highest child obesity rate in 2011 with more than a quarter (26.45%) of children classed as obese.
Meanwhile, Richmond and Twickenham PCT had the lowest level, with 10.67 per cent classed as obese in 2011.
The biggest percentage increase in obesity rates was reported by Hastings and Rother PCT, which showed a 43.5 per cent increase amongst ten to eleven-year-olds in the past five years.
The biggest reduction was reported by Portsmouth City Teaching PCT, which showed a fall in the proportion of obese children from 24 per cent in 2007 to 19 per cent in 2010/11.
In 2011, the obesity rates in the most deprived areas in England averaged 23.4 per cent, compared with 15.68 per cent in the least deprived areas.
Judy Aldred, managing director of SSentif: "Childhood obesity is one of the most pressing public health concerns we have to tackle and yet rates have increased over the last five years, despite the Government's attempts to curtail them.
"We've just hosted a fantastic Olympic Games and the legacy of those games has to be to improve the health and fitness of our children. This is the perfect time to focus on this issue and to take steps to tackle the problem."