Child obesity is one of Dorset’s ‘hidden issues’, the boss of a school meals supplier has warned after it was revealed Weymouth and Portland had the highest prevalence of obesity in the county last year.

Figures from NHS Digital show that in 2016/17, 9.1 per cent of reception-age pupils measured in the borough were declared obese. Of Year 6-age pupils, 17 per cent were at the same unhealthy weight.

Overall, more than one in three Year 6 pupils were declared overweight or obese.

In contrast, Poole had the lowest prevalence of child obesity at 6.7 per cent in reception pupils and east Dorset saw the lowest in Year 6 pupils at 10.7 per cent.

It is one in a series of grim revelations for the “left behind” borough after it came almost bottom of the pile for social mobility, was revealed to have the country’s lowest weekly wages and Dorset’s worst life expectancy rates.

The figures form part of the National Child Measurement Programme (NCMP) overseen by Public Health England (PHE) and analysed and reported by NHS Digital.

The NCMP is a key element of the government’s approach to tackling child obesity.

Caroline Morgan, chief executive of Local Food Links which provides healthy meals to schools across Dorset, thinks the issue of childhood obesity is a ‘hidden problem’ in the county and “will get worse before it gets better”.

She said: “Fresh fruit and vegetables are costlier than food that is high in salt, sugar and fat.

“It’s difficult to say to families what they should be eating well when they are struggling with a smaller income.

“We absolutely cannot sit in judgement at families who need to buy whatever will fill hungry bellies.

“The price of food is increasing but wages are not.

“It’s much more of a problem in Dorset than people think, there are very few areas that are not affected.

“We have affluent areas next to deprived areas and it’s masking the problem. It is going to get worse before it gets better.

“Children in this county are absolutely relying on a free school meal to keep them going during the term.

“Hungry children simply cannot learn.”

The NCMP works out obesity using the 1990 British growth reference chart - a collection of statistics which work out a child’s body mass index (BMI). It defines a child as obese if their BMI is in the top five per cent, and overweight if they are in the top 15 per cent.

NHS Digital says child obesity is a good indicator of adult obesity which can lead to poor health outcomes, and according to PHE, a third of children in the UK are leaving primary school overweight or obese.