Title: More Robust Evidence to Advance the UK Salt Reduction Programme
Funder: Department of Health and Social Care

Abstract: Salt intake in the UK averages at ~8 g/d; well above the World Health Organization's 5 g/d recommended maximum intake. Via raised blood pressure, high salt intake is a major risk factor for cardiovascular disease, a leading cause of death and disability. The UK has a salt reduction programme, which is predominantly based on the setting of targets for the salt content of foods to encourage their reformulation. So far, salt targets for 2010, 2012, and 2017 have been set; salt targets for 2023 have been drafted but not yet set. Long viewed as a public health success story, the UK salt reduction programme is now poorly implemented, and no progress in salt reduction has been made since 2014. The overall aim of this research is to provide concrete evidence to strengthen the UK salt reduction programme to reduce population salt intake. Three studies will be conducted, on the (i) salt content of supermarket foods, (ii) salt content of out-of-home foods, and (iii) potential health and economic impact the salt reduction programme, respectively. First, a mixed-methods study (to be completed by December 2022), where changes in the salt content of supermarket foods over time will be assessed, followed by semi-structured interviews with industry and governmental informants on how to overcome barriers to salt reformulation in the supermarket food categories contributing most to salt intake in the UK. Second, the development of a database of the nutritional content and price of out-of-home foods using information available online, with web scraping to be automated from early 2022 and continue thereafter on a weekly basis, so that by 2024 sufficient data will be available to determine whether the 2023 salt targets were effective in lowering salt content in the out-of-home sector. This will be complemented by a cross-sectional survey (to be completed by March 2024) of a representative sample of UK out-of-home businesses on their salt use, the extent to which it is controlled, and existing measures to reduce it. Third, a modelling study (to be completed by September 2024) in which the health and economic impact of achieving all 2023 salt targets in both supermarket and out-of-home foods will be estimated. The number of cardiovascular events and deaths that would be prevented will be obtained by estimating, in consecutive steps, changes in the following parameters: salt content of foods, individuals' salt intake, individuals' blood pressure, and population incidence and mortality rate in ischaemic heart disease and stroke. Cost savings will be estimated using cost figures for the UK salt reduction programme, disease-specific healthcare, and disease-specific productivity losses. Results will be communicated to policymakers, food industry and catering representatives, and the wider public via the advocacy work of Action on Salt, an independent non-profit charitable organisation who will collaborate closely in this research. Reviving and strengthening the UK salt reduction programme would bring enormous benefits in preventing chronic diseases as well as major cost savings. This research will have implications for salt reformulation worldwide as well as for other types of reformulations.

Lay abstract: We eat far too much salt in the UK. This puts up our risk of cardiovascular disease, which is what kills us most after dementia and costs the nation over 23 billion each year. This is why in 2003, the UK started a nation-wide salt reduction programme where food companies committed to lower salt in their products. The reduction was made gradually so that consumers could not notice any change in taste. This strategy was at first extremely effective at making us all eat less salt. Each year, 9000 cases of heart disease and strokes were prevented, and this saved the NHS 1.5 in annual healthcare costs. Then, due to political changes and poor management, the programme lost steam. Our salt intake has not gone down since 2014 and is still too high: over 8 grams a day, while the World Health Organization recommends a maximum of 5. With this research, my goal is to revive and strengthen the salt reduction programme, which is the only way to make sure everyone eats less salt (since the programme works on directly improving all foods made available to us, instead of relying on each one of us to make the right dietary choices while surronded by unhealthy options). Together with Action on Salt, the UK's leading and science-based charity on salt reduction, I will research and obtain the information needed to strengthen the salt reduction programme. I will start with supermarket foods, and look at how much salt they contain. Do they contain more, less, or the same amount of salt they used to? Two-thirds of the salt we eat comes from bread and meat products. I will talk to their manufacturers: from those producing high-salt products, I want to find out what prevents them from using less salt; from those producing lower-salt products, I want to know what solutions they have found. I will then ask governmental staff what measures they could put in place to encourage manufacturers to use less salt. The meals we eat away from home are also very salty. Anyone can find their nutritional information online, but this often means visiting websites one by one. I will develop a software to automatically extract all this online data into one single database. This way, I will make it easier to keep track of whether the salt reduction programme works in making those meals contain less salt. I will also ask businesses how, why, and when exactly they add salt when preparing food, and what support they would need to reduce salt, so that I can advise the government on how to best help them do so. I will also calculate how many of us would not develop or die of chronic diseases if our food contained the amount of salt recommended, and how much money our society would save this way. This is to convince the government of how important and urgent it is to revive and strengthen the salt reduction programme. Finally, using Action on Salt's network, I will ensure my research findings reach those people who can contribute to the salt reduction programme and make sure it is applied on the ground. Action on Salt has been active since 1996 and has by now built an extensive network of governmental staff, non-governmental organisations, healthcare professionals, and members of the food industry. By putting the UK salt reduction programme back on track, this research will help save not only lives, but also money. The lessons learned here will also be valuable internationally, as eating too much salt is the leading cause of death in the world.

Research activity codes: 3.1 PRIMARY PREVENTION INTERVENTIONS TO MODIFY BEHAVIOURS OR PROMOTE WELL-BEING
Health categories: GENERIC HEALTH RELEVANCE