UK’s voluntary salt-reduction programme linked to thousands of heart disease, stroke and cancer cases

There will be 26,000 extra cases of heart disease/stroke and 3,800 cases of stomach cancer by 2025, without a change to the UK’s current strategy on salt reduction, researchers have warned.

The UK introduced the Public Health Responsibility Deal in 2011. This was a voluntary pact made between the UK government and industry to improve the nation’s health by, among other things, reducing the salt content of food.

But a study published in the Journal of Epidemiology & Community Health​ claims that the reduction in salt intake has slowed in England since the introduction of the pact.

It suggests the strategy may have been responsible for an additional 9,900 cases of heart disease/stroke and an extra 1,500 cases of stomach cancer up to 2018 -- diseases both associated with excess dietary salt ─ compared with the period before the pact.

Without a change in strategy, this toll is estimated to reach 26,000 extra cases of heart disease/stroke and 3,800 additional stomach cancer cases by 2025, according to the researchers.

If current trends in salt intake continue, the equivalent estimates rise to 26,000 extra cases and 5,500 extra deaths from heart disease/stroke and 3,800 additional cases of stomach cancer by 2025, compared with the trends before 2011. 

This would widen health inequalities in the process, and add up to more than £1bn in healthcare and lost productivity costs, they calculate.    ​​

‘Voluntary schemes aren’t properly evaluated’​

Despite the international popularity of public-private partnerships, such as the Responsibility Deal, to improve population health, these collaborations tend not to be properly evaluated, said the researchers. 

To try and rectify this, they drew on data from the National Diet and Nutrition Survey (2000, 2001) and national sodium intake surveys taken from the Health Survey for England for the years 2006, 2008, 2011 and 2014.

They then assessed the effect of changes in dietary salt intake on new cases of heart disease/stroke and stomach cancer, using a validated mathematical method (IMPACT) that closely mimics the impact of changing risk factors on the development of disease. 

These data sets were then combined with published estimates of the healthcare and workplace productivity costs associated with cardiovascular disease and stomach cancer. 

In 2000-01, average daily dietary salt intake was 10.5 g for men and 8 g for women in England. Between 2003 and 2010, average annual intake fell by 0.2 g among men and by 0.12 g among women. 

But between 2011 and 2014, annual reductions in dietary salt intake slowed to 0.11 g among men and to 0.07 g among women. 

IMPACT analysis estimated that between 2011 and 2018 this trend may have been responsible for around 9,900 extra cases of heart disease/stroke plus 710 associated deaths, as well as 1,500 additional cases of stomach cancer and 610 associated deaths. 

This is an observational modelling study, and as such can’t establish cause, added to which the researchers acknowledge that their study did not collect long term data on salt intake in the same people, which may have affected the findings.

Nevertheless, their findings echo those of other studies and official data, they point out. They also highlighted that the Responsibility Deal may have been particularly unfavourable for those living in the most deprived areas of the country, widening, rather than narrowing, health inequalities. 

“Public-private partnerships such as the [Responsibility Deal], which lack robust and independent target setting, monitoring, and enforcement are unlikely to produce optimal health gains,”​ they concluded. 

‘It’s up to the UK government to tell the food industry what to do’​

“This paper confirms once more that the Responsibility Deal was a disaster for public health in that it slowed down salt reduction in the UK, resulting in thousands of strokes, heart failure and heart attacks every year, particularly in the more socially deprived, many of which could have been prevented​,” said Graham MacGregor, Chairman for Action on Salt.

He added that the move reinforces the urgent need for a robust system where we generate worthwhile reductions in salt intake which make a positive and lasting impact.

“It is now up to the Health Minister, Public Health England and the Government to set up a coherent strategy where the food industry is instructed what to do, rather than the food industry telling the Government what to do, which currently seems to be the case,”​ he said.

“The UK currently has no active salt reduction strategy which is appalling. In fact, the last set of salt reduction targets expired at the end of 2017. It goes without saying, we now need to get our salt reduction strategy back on track for the benefit of public health, our overburdened NHS and the economy."​

However, the Food and Drink Federation (FDF) has defended the sector's record on salt reduction. The food industry organisation pointed out that consumer acceptance is a 'significant challenge' for reformulation work but insisted that progress has nevertheless been made. 

According to FDF data, products produced by its members provide 14% less salt into the average shopping basket than they did four years ago. 

Public Health England tests demonstrate average salt intakes, based on urinary sodium over a 24-hour period, are 'decreasing', FDF continued. Adult intakes have decreased from 8.8 g/day in 2005/06 to 8.0 g/day in 2014, representing an 11% decrease over the past decade. PHE has indicated that the next urinary sodium data was collected last year and will be published this year.