The National Institute for Health and Clinical Excellence (Nice) says that unhealthy foods have wreaked a “terrible toll of ill health” on the nation and placed a “substantial” strain on the economy.

For the first time, the organization publishes landmark guidance on how to prevent the “huge number of unnecessary deaths” from conditions such as heart disease that are linked to the consumption of ready meals and processed food.

It calls for sweeping changes to food production and government policy to encourage lifestyle changes, and to reduce significantly the amount of salt and saturated fat the nation consumes.

It says “toxic” artificial fats known as trans fats, which have no nutritional value and are linked to heart disease, should be banned. The organization says that ministers should consider introducing legislation if food manufacturers failed to make their products healthier.

Nice says it has brought together all the available evidence to illustrate the link between unhealthy food and public health, partly in response to increasing concern about obesity in Britain, particularly among children.