By Year 6 this nearly doubles, with one in three children being classified as obese.
The programme's 2008/09 report also found that the prevalence of obesity is significantly higher in boys than in girls in both age groups.
It found higher than national averages for obesity in children living in London, the north-east and the West Midlands.
However, the report claims that the rise in child obesity has levelled off, with the number of reception-age children who are obese remaining the same in 2008/09 as in 2007/08.
This echoes data from the National Heart Forum last month which suggested that obesity in children may be levelling off rather than increasing (News, 12 November).
Tam Fry of the National Obesity Forum said, 'The figures are more or less the same as last year, but we need to have two to three years' worth of figures to prove that this is not a blip. It will be another couple of years before we can break open the champagne.'
Commenting on the Government's Start4life campaign, announced earlier this month (News, 3 December), Mr Fry said, 'It won't work well, as it's leaflets and posters which people don't look at and throw away. Any meaningful messages need to be put in a direct fashion, and that's where childcare practitioners are so important. Money should be used to recruit more early years and medical staff who can teach parents about breastfeeding, weaning and nutritious food.'
The National Obesity Forum is calling for a tax on fizzy drinks, which it says have a negative effect on children's weight and dental health, and for the tax money raised to be used to fund anti-obesity measures.
and less than a one percent rise in the number of fourand five-year-olds who are overweight.