Several studies have shown that excessive sodium consumption can cause an increase in blood pressure and expose to a greater risk of cardiovascular disease.
For this reason, for many years products that replace salt have been proposed, providing flavor to foods, but containing low percentages of sodium. Most of these products mainly contain potassium chloride.
Potassium is usually assumed in smaller quantities in the daily diet than sodium and can enrich the flavor of foods almost as natural salt.
However, the increased consumption of potassium is not without risks. Various diseases and drugs can reduce the body’s excretion of potassium, thus increasing the risk of its excessive concentration in the blood, which can potentially drive serious events.
Therefore, people with kidney failure, heart failure or diabetes are not recommended to use salt substitutes without prior medical evaluation.
On the other hand, reducing sodium intake is certainly useful for reducing blood pressure and it has been shown that salt substitutes, with reduced sodium and increased potassium levels, are able to reduce it.
However, the potential adverse effects related to an increase in potassium consumption with the use of salt substitutes have never been defined.
A new randomized, open-label study, published in the New England Journal of Medicine, tried to clarify the potential risks associated with the use of salt substitutes in a population at high risk for cardiovascular disease.
The trial was conducted in 600 villages in rural areas of five Chinese provinces and included subjects with a previous stroke or with hypertension poorly controlled by therapy and aged 60 years or more.
Randomization was applied at village level and participants were assigned to the intervention group, in which they used a salt substitute, or to the control group, in which they continued to use regular salt.
The primary end point of the study was stroke, while secondary endpoints included major cardiovascular events and death from any cause.
Clinical hyperkalaemia was evaluated as a safety endpoint.
A total of 20,995 people were enrolled, with an average age of 65 years. Among them, 73% had a stroke and 88% had hypertension. The mean duration of follow-up was 4.74 years.
The results of the study showed that in the villages where salt substitute was used, compared to those where normal salt was consumed, fewer strokes were recorded.
Major cardiovascular events and death were also less frequent with the use of salt substitutes.
Concerning the most original aspect of this research, the adverse events related to the increase in potassium consumption, only two cases of definite or probable hyperkalaemia were documented during the follow-up: one was recorded in the group of patients using the salt substitute and one in the control group. A possible hyperkalaemia was hypothesized in a further 313 subjects.
On the other hand, no significant difference was found between the two study groups regarding any type of hyperkalemia detected, as well as for the rate of related serious adverse events.
Therefore, overall, this study provides reassuring information. On the one hand, it confirms the fact that salt substitutes can reduce the rate of stroke, major adverse cardiovascular events and death. On the other, it demonstrated that the use of the salt substitute was not associated with any apparent serious adverse effect.
This post is also available in: Chinese (Simplified)