Dr. Feng He
Wolfson Institute of Preventive Medicine
Barts and The London School of Medicine and Dentistry
Queen Mary University of London, London, UK
MedicalResearch.com: What are the main findings of the study?
- The UK salt reduction program has led to a fall in population blood pressure and thereby contributed to the reduction in stroke and heart disease deaths.
- In 2003, the UK Food Standards Agency and CASH (Consensus Action on Salt & Health) developed a salt reduction program. As approximately 80% of the salt in the diet is added to food by the food industry i.e. in processed foods, fast foods, canteen and restaurant foods etc, the public have no choice about eating it. Therefore progressive incremental targets to limit the amount of salt for each food category were set, which the industry had to achieve in a specified time. Reductions first started in 2003 and are continuing to this day.
- The salt reduction program has been very successful and led to a 15% reduction in the average salt intake of the population, from 9.5g per day in 2003 to 8.1g per day in 2011 (P<0.05).
- Over the same time period, blood pressure fell in the adult population by 3 mm Hg systolic and 1.4 mm Hg diastolic (P<0.0001). Stroke and heart disease deaths fell by 42% (P<0.0001) and 40% (P<0.0001) respectively.
- It is possible that these falls in blood pressure and deaths from stroke and heart disease were attributable to various factors such as changes in diet, lifestyles and the improvement in the treatment of cardiovascular disease and its risk factors. Our further analysis showed that the reduction in salt intake played an important role, particularly in the falls in blood pressure.
- In a further analysis, we looked at individuals who were not on any drug treatment for blood pressure and a correction was made for all other variables that could have influenced blood pressure, apart from salt. There was still a fall in adult population blood pressure of 2.7mm Hg systolic/ 1.1mm Hg diastolic, (P <0.0001). This reduction in blood pressure could therefore be largely attributed to the fall in salt intake.
- It is well established that raised blood pressure throughout its range is a major cause of stroke and heart disease. The reduction in salt intake that led to a fall in blood pressure would have played an important role in both stroke and heart disease deaths.
- Despite considerable progress being made on salt reduction, the average salt intake in England is still high. In 2011, it was 8.1 g/day which is over a third more salt than the recommended level of 6g/day. Therefore continuing and much greater efforts are needed to achieve further reductions in salt intake to prevent the maximum number of stroke and heart disease deaths.
MedicalResearch.com: What should clinicians and patients take away from your report?
- Patients should reduce their salt intake.
- Do not add salt at the table;
- Do not add salt or ˜flavor enhancers” made from salt such as stock cubes, soy sauce, when preparing food or during cooking; use herbs, ginger, garlic, pepper, vinegar, lemon or lime juice to add flavor instead;
- When eating at restaurants, ask the chef to add less salt to your meals;
- Importantly, check food labels for salt, compare products, brands and varieties, and choose lower salt options.
- FoodSwitch, a free and easy to use health app, lets you scan the barcode of a product and provides you with clear nutritional information with colour-coded ratings for the four key food components – total fat, saturated fat (saturates), sugars and salt. It also gives you a list of healthier choices.
- FoodSwitch is available as a free, UK-only download from iTunes and Google Play. – See more at: http://www.actiononsalt.org.uk/foodswitch/#sthash.zoB8DYAa.dpuf
- SaltSwitch is a feature of the app, which focusses on the salt content of the food, and gives you a list of less salty alternatives http://www.actiononsalt.org.uk/foodswitch/FAQ/119965.html#AboutSaltSwitch
MedicalResearch.com: What recommendations do you have for future research as a result of this study?
- The evidence for the benefit of salt reduction is very clear. The results of our study indicate that we need to redouble our efforts in the UK, in particular to get the food industry to act faster and more aggressively to save the maximum number of people from suffering and dying from stroke and heart disease.
- Other countries should follow the UK’s lead. All countries should adopt a coherent and workable strategy to reduce salt intake.