Fast-food outlets, supermarkets, restaurants and food manufacturers should cut calories in their products by 20% to help tackle the childhood obesity crisis, England's health watchdog has demanded.

Public Health England (PHE) has "challenged" the processed food industry to make the reduction by 2024, after it established that some children are eating the equivalent of an extra meal a day.

"Britain needs to go on a diet," said Duncan Selbie, chief executive of PHE.

"The simple truth is on average we need to eat less.

"Children and adults routinely eat too many calories and it is why so many are overweight or obese.


"Industry can help families by finding innovative ways to lower the calories in the food we all enjoy.

"It is not an attack on overweight folk, it is about getting more options and extending knowledge and more choices."

How well do you know your calories?

PHE is also launching a campaign to encourage people to control calories, proposing a "rule for thumb" of 400 calories for breakfast and 600 each for lunch and dinner.

They say major fast-food chains including McDonalds, Subway and Greggs have signed up to the "400-600-600" plan and agreed to "signpost" customers towards lower-calorie options.

"We are talking to big companies that make the big-selling products, both ready meals and out-of-home food," said chief nutritionist Alison Tedstone.

"A few healthy options at the end of a menu will not end the obesity crisis.

"We need the everyday products to change."

Image: Obesity causes a range of health problems

Research by PHE estimates that some children eat between 290 and 500 unnecessary calories every day, the equivalent of an extra meal.

Processed food, ready meals and those eaten away from the home account for 50% of all calories consumed, and 19% of those eaten by children.

Producers have been asked to cut the calories in 13 processed food categories including pizzas, savoury snacks, soups, meats, potato and pasta meals, and "composite" salads such as hummus.

Suppliers will be encouraged to "reformulate" their recipes to cut calories or reduce portion size to meet the targets, which are voluntary.

Last year PHE launched a similar sugar reduction program which, combined with a new levy on soft drinks and the food program, will target 50% of the calories consumed by children.

PHE estimated the programs could save the NHS £4.8bn over the next 25 years, a further £4.2bn in social care costs and prevent 35,000 early deaths.

Obesity and related conditions including Type 2 diabetes and some cancers cost the NHS £6bn every year, as well as "keeping people out of work, stifling their earnings and wider economic productivity".