Food manufacturers are being challenged to cut calories in products by a fifth by 2024.
Public Health England (PHE) said industry could cut calories by changing product recipes, reducing portion sizes and encouraging consumers to buy lower-calorie products.
The categories of food covered by the programme include pizzas, ready meals, ready-made sandwiches, meat products and savoury snacks.
PHE said more than 35,000 premature deaths could be prevented and £9bn in healthcare costs saved, over 25 years, if the target is met within five years. If firms do not act PHE has said it could ask the government to legislate.
PHE said adults consumed on average 200-300 excess calories each day. Overweight and obese boys consume 140-500 calories too many and for girls the figure is 160-190.
Duncan Selbie, chief executive at PHE, said: “The simple truth is on average we need to eat less. Children and adults routinely eat too many calories and it’s 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 and promoting UK business leadership on the world stage in tackling obesity.”
PHE said the 20% target was the result of analysis of calorie consumption data, experience of sugar and salt reduction programmes and meetings with industry and stakeholders.
The next step in the programme involves engagement with retailers, manufacturers, major restaurants, cafes, takeaway and delivery companies and the health and charity sectors to develop category guidelines, which are due to be published in mid 2019.
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