We are attributing it, not surprisingly, to diet and a lack of physical activity

Dr Mary Rudolph

The issue of obesity in children was highlighted recently by the case of five-year-old Georgina Beauchamp, from Tewkesbury, Gloucestershire.

Georgina, who weighed five-and-a-half stones, hit the headlines after the headmaster of her primary school wrote to her parents expressing concern about her weight.

Her parents denied their daughter had a problem and later removed her from the school.

Couch potatoes

Health experts blame a couch potato mentality for the growing weight problems, which are leading to an increase in childhood diseases such as asthma and diabetes.

Dr Mary Rudolph, a paediatrician at the Leeds Community and Mental Health Trust, said overweight children would become unhealthy adults.

"We are attributing it, not surprisingly, to diet and a lack of physical activity."

She said children should be educated as early as possible to eat healthily.

"Primary schools are a good place to start because the problems tend to start at that age and children at that age are more malleable to lifestyle changes."

The study, published in the British Medical Journal (BMJ) showed that one in five nine-year-old boys and girls was overweight and one in 10 obese.

A quarter of all 10-year-olds were overweight while as early as the age of seven, 14% of girls and 10% of boys were considered unhealthily fat.

Overall, 22% of all boys and girls aged seven to 11 were overweight, with 11% of all girls and 12% of all boys classed as obese.