Relaxing salt regulations in the UK has been linked to thousands of cases of heart disease and stomach cancer that would never have otherwise occurred, research suggests.
A study looked at salt intake in England before and after changes to legislation were introduced in 2011.
The 'tragic' Public Health Responsibility Deal saw the food industry set its own salt targets, rather than being monitored by an independent body.
Researchers blame this for an additional 9,900 cases of cardiovascular disease and 1,500 stomach cancer diagnoses in 2011-to-2017.
Adults are advised to consume no more than one teaspoon (6g) of salt a day, while children should have half this.
However, two thirds of us are thought to eat 8g of salt due when we overindulge in ready meals, processed meats and bread.
Salt raises blood pressure, which puts a strain on the heart. It may also damage the stomach lining and cause lesions that become cancerous.
Relaxing salt regulations in ready meals 'caused 9,9000 cases of heart disease' (stock)
The research was carried out by Imperial College London (ICL) and the University of Liverpool. It was led by Dr Anthony Laverty, lecturer in the school of public health at ICL.
Study author Dr Martin O'Flaherty, professor of epidemiology at the University of Liverpool, said: 'We are eating too much salt.
'Previous research has shown three-quarters of salt in our diet is hidden in processed food such as bread, ready meals and soups.'
Before the changes were introduced in 2011, salt intake was steadily falling every year by 0.2g for men and 0.12g a day for women.
When the regulations were relaxed, this slowed to a decline of 0.11g a day for men and 0.07g for women.
Between 2003 and 2010, the Food Standards Agency (FSA) closely monitored salt content and agreed on targets to reduce consumption with the industry.
For example, the FSA requested food manufacturers reduce salt content by between 10 and 20 per cent.
At the same time, public health campaigns pressured the Government into stricter regulations.
However, in 2011 the FSA's role was replaced by the Public Health Responsibility Deal.
This allowed food manufacturers to choose whether to sign up to salt-reduction targets.
'Evidence from around the world is now showing that mandatory approaches are much more effective than self- regulation by industry in reducing the amount of salt and sugar in our diet,' Dr Laverty said.
The researchers analysed data from the National Diet and Nutrition Survey, as well as other 'salt studies' carried out between 2000 and 2013.
The vast majority of packaged foods in the UK come with nutritional information printed on the label.
The main things to look for are fat, saturated fat, salt (which may be called sodium), fibre and sugar – which is often listed as 'of which sugars' beneath carbohydrates.
Generally speaking, foods with higher fibre and lower saturated fat, salt and sugar are healthier.
Some supermarkets also label nutritional value with a traffic light system, in which more green points to healthier food.
The NHS advice on what is high or low is as follows:
High: more than 17.5g of fat per 100g
Low: 3g of fat or less per 100g
An adult's recommended daily allowance (RDA) of fat is around 70g.
High: more than 5g of saturated fat per 100g
Low: 1.5g of saturated fat or less per 100g