Background Dietary salt intake has been causally linked to high blood pressure and increased risk of cardiovascular events. Cardiovascular disease (CVD) causes approximately 35% of total UK deaths, at an estimated annual cost of £30 billion with £14.4 billion spent on treating CVD per year. WHO and NICE have both strongly recommended dietary salt reduction. However, to implement more effective policies in future, UK policy makers will need robust evidence to assess the costs and benefits of specific interventions.
Methods A validated model called IMPACT CHD, calibrated for England’s population aged 25 to 85+ years, was used to quantify and compare four population salt reduction policies. These interventions comprised: 1) Change4Life health promotion campaign, 2) front of pack traffic light labelling to display food salt content, 3) Food Standards Agency continuing to work with the food industry to reduce salt on a voluntary basis or 4) Mandatory reformulation (legislation) to reduce salt in processed foods. The effectiveness of these policies in reducing salt intake, and hence blood pressure, was determined by systematic literature review. The IMPACT CHD model was used to calculate the reduction in mortality associated with each policy, quantified as life years gained over 10 years. The cost of each policy used published evidence from the Department of Health and Food Standards Agency. Health care costs for specific CHD patient groups were estimated and compared against a “do nothing” baseline. A ten-year time horizon was taken from 2007 (the model baseline year) to 2017. Policy and health care costs were discounted at 3.5%. Probabilistic sensitivity analysis was used to quantify uncertainty.
Results All policies resulted in a life year gain over the baseline. Change4life and labelling each resulted in a gain of approximately 1960 life years, voluntary reformulation a gain of some 14,560 life years and mandatory reformulation approximately 19,320 life years. The costs of each policy appeared cost saving against the baseline. Mandatory reformulation apparently offered the largest cost saving, over £660 million compared to baseline.
Conclusion All population health interventions to reduce dietary salt intake on an English population appear cost saving and could substantially reduce health care expenditure on cardiovascular disease. Mandatory reformulation of processed foods might achieve the highest reduction in dietary salt intake and therefore the largest savings.