Replacing regular salt with a salt substitute lowers blood pressure and protects against life-threatening heart conditions, stroke and death from all causes, research suggests.
High consumption of salt composed of sodium chloride is known to drive blood pressure up, leading to poor cardiovascular health and posing a major risk of early death.
However, research published in the journal Heart has revealed that swapping regular salt for a substitute, in which a portion of the sodium chloride is replaced with potassium chloride, reduces these health risks.
The study compiled results from 21 clinical trials, involving nearly 32,000 participants, published up to the end of August 2021 and reporting the effects of salt substitutes on blood pressure.
The team from the George Institute for Global Health in New South Wales, Australia, and Imperial College London, found that salt substitutes reduced blood pressure in all participants, regardless of region, age, sex, weight and blood pressure-related factors.
“Salt substitutes produce consistent blood pressure-lowering effects across geographies and diverse participant subsets,” the researchers write.
No adverse effects were detected from the increased intake of potassium chloride. The effect of potassium chloride added to salt substitutes has, however, raised concerns for people with kidney disease, who should limit dietary potassium intake.
When the researchers carried out a smaller analysis of just over 24,000 participants, they found that switching to salt substitutes reduced the risk of heart attack, stroke and early death from any cause by 11%. The risk of cardiovascular disease was reduced by 13%.
Similar results were published in a study last year, involving over 20,000 participants with high blood pressure from 600 villages in China. It was unclear, however, whether the benefits from salt substitutes would be the same in other parts of the world.
“These findings are unlikely to reflect the play of chance and support the adoption of salt substitutes in clinical practice and public health policy as a strategy to reduce dietary sodium intake, increase dietary potassium intake, lower blood pressure and prevent major cardiovascular events,” the researchers write of the new study.
More than 14 million people in the UK have high blood pressure, about 5 million of whom are undiagnosed, according to the British Heart Foundation (BHF). High blood pressure contributes to around half of all heart attacks and strokes in the UK.
Tracy Parker, a heart health dietitian at the BHF, said: “This research is a helpful reminder to cut the amount of salt we have in our diets and to look for alternatives.”
But Parker cautioned: “While low salt substitutes have less sodium than regular salt, they still contain potassium which may not be suitable for some people with a heart problem and other existing health conditions. If you want to look after your health, it’s better to just eat less salt. Using different herbs and spices when cooking is a great way to add flavour and replace salt.”
