A school wear retailer is expanding its range of larger uniforms in response to demands from parents struggling to find clothes for their outsize children.
School uniforms are getting larger, alongside pupils
National Schoolwear Centres will now stock its stores with 52-inch-chest blazers, trousers with 42-inch waists and shirts with 17.5-inch collars.
Previously these sizes were only available by special mail order.
The British Heart Foundation said the move was a reflection of the growing number of children becoming obese.
National Schoolwear Centres' managing director, Graham Michelli, said the trend was that boys, in particular, were getting bigger.
"These sizes are no longer specials, which reflects the volume demand for them," said Mr Michelli.
"Year on year we're seeing an increase of about 25% in demand for the 50 and 52 inch blazer.
"Overall, the size of children's uniforms is slightly increasing, the averages are slowly getting bigger."
Mr Michelli said trousers legs were also lengthening, with a 36-inch inside leg now part of standard stock.
The British Heart Foundation said the government would have to do more to tackle the rise in childhood obesity.
The government has pledged to halt the rise of obesity among children under-11 by 2010.