A head teacher has banned crisps from lunchboxes after the latest warnings on childhood obesity.

Chasey Crawford-Usher, in charge of Wateringbury Primary School near Maidstone, is now only allowing the calorific snacks to be brought in one day a week.

The policy follows a ban on juices at the Bow Road school put in place in 2015.

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It comes after figures showing almost one in five Year 6 pupils in the area are classed as obese.

Ms Crawford-Usher said: “Just like we insist on no sugary drinks, we’re going to set out crisps only on a Friday.

“I’m not the food police. Parents are responsible ultimately for the health and wellbeing of their children.

"All I can do is insist when they’re in our school they follow our best guidelines.”

At the school, teachers are encouraged to take pupils out of the classroom three times a week for a 10-minute run, on top of the two hours of physical education required by government.

But Ms Crawford-Usher believes some schools may be cutting that time short, saying: “We have two different PE sessions, both in the afternoon, which makes them difficult to fit in.

“I know that’s a pressure on schools because we have to meet high standards in maths and English and we also have to fit in a lot of requirements in terms of non-core subjects.

“It’s tempting for schools to cut back on PE times because they need to keep the pressure on producing the results in maths and English.”

She said everything she did at the school was in the best interests of the children.

She added: “If parents kick back, I can only say that I’m trying to set good habits.”

The head's tough stance on crisps and fizzy drinks comes as the average number of Kent’s four to five-year-old pupils classed as obese and overweight reached 22.5%.

Earlier this month Kent figures showed Dartford and Gravesham had the largest percentage of older primary school children in Kent who are overweight or obese.

The latest health figures show a massive 38.9% of 10 to 11-year-olds resident in Gravesham fall into this category, with Dartford only slightly slimmer at 35.6%.

The figures were published by government-sponsored agency Public Health England (PHE)

Dartford has 25.6% of Reception Year pupils – four to five-year-olds – classified as obese and overweight, again the highest in Kent It is also above the Kent average of 22.5% and national average of 21.9%

Closer to Tonbridge and Malling, new research shows in the neighbouring borough of Maidstone almost one in five Year 6 pupils in Maidstone are classed as obese.

Public Health England’s calculations reveal 16% of Year 6 pupils around the borough were declared obese between April 2016 and March 2017, while nearly 3% were classified severely obese.

"If parents kick back, I can only say that I'm trying to set good habits" - Chasey Crawford-Usher

On top of that, 15% of Year 6 children were described as overweight, meaning more than a third of Maidstone’s youngsters were unhealthily overweight as they entered secondary school.

More than 30,000 children in Kent and one million in England were measured as part of the National Child Measurement Programme to categorise youngsters as underweight, healthy, overweight or obese.

Public Health England will look at unhealthy meals which children are eating, such as pizzas, burgers and ready meals, and will come up with a comprehensive calorie reduction programme later this year.

In April the sugar tax will come into effect, applying an extra levy on soft drinks with a sugar content of more than 5g per 100ml, such as Coke, Red Bull and Dr Pepper.

On average, children aged four to 10 are consuming 22kg of added sugar a year – approximately 5,500 sugar cubes and more than the weight of an average five-year-old.