Replacing Regular Salt with Salt Substitute Reduces Hypertension Risk, Study Finds
A recent study has found that replacing regular salt with a salt substitute can significantly reduce the risk of developing hypertension. The study, conducted in China, showed that older adults who swapped table salt for a salt substitute were 40% less likely to develop hypertension over a period of 2 years compared to those who continued using regular salt.
The salt substitute used in the study consisted of 62.5% sodium chloride, 25% potassium chloride, and 12.5% flavorings. Lead author Yangfeng Wu, MD, PhD, professor and executive associate director at Peking University Clinical Research Institute in Beijing, China, emphasized the importance of this finding from a public health perspective. He stated, “Our study results indicate that everyone in the whole population, either hypertensive or normotensive, can benefit from replacing regular salt with potassium-enriched salt substitute. Thus, salt substitution should be considered and promoted as a whole-population strategy for prevention and control of hypertension and cardiovascular disease.”
The study, known as the DECIDE-Salt clinical trial, was a cluster-randomized trial conducted in 48 residential elderly care facilities in China. It involved 1612 participants aged 55 years or older. The trial compared the effects of two sodium reduction strategies: replacing salt with a salt substitute and progressively restricting the salt supply. The results showed that the salt substitute intervention significantly lowered systolic/diastolic blood pressure compared to the usual salt group. On the other hand, progressive salt restriction had no impact on blood pressure.
A post hoc analysis of the DECIDE-Salt trial focused on 609 participants who were normotensive at baseline. The results revealed that the salt substitute group had a lower incidence of hypertension over 2 years compared to the usual salt group. There was no increase in episodes of hypotension in the salt substitute group. Additionally, the salt substitution group experienced no change in mean systolic/diastolic blood pressure over the 2-year period, while the usual salt group had a significant increase in blood pressure.
These findings are consistent with a previous study from Peru, which also showed a lower risk of developing hypertension in the salt substitute group. The study in Peru primarily involved normotensive participants, suggesting that salt substitution may be beneficial for younger adults as well.
Ankur Shah, MD, from the Division of Kidney Disease and Hypertension at Warren Alpert Medical School of Brown University, commented on the study, noting its significance in the context of limited and conflicting reports on the effects of salt substitution in individuals with normal blood pressure. Shah stated, “The study certainly has population-level implications, as the design of a cluster-randomized trial at the facility level makes for a clear path to implementation — sodium substitution in elderly care facilities. That said, this is also the greatest limitation — extrapolating to the general population may not be accurate.”
While the study highlights the potential benefits of salt substitution, there are concerns regarding its use in patients with kidney disease. These patients are typically advised to lower their potassium intake, and supplementing potassium through salt substitutes could lead to hyperkalemia, a condition that can be life-threatening. Therefore, caution should be exercised in such cases.
In conclusion, the study provides compelling evidence that replacing regular salt with a salt substitute can reduce the risk of developing hypertension. This finding has important implications for public health, and it is suggested that strategies for wide-scale implementation of salt substitutes should be prepared by the food industry and authorities. However, further research is needed to determine the applicability of these findings to the general population and to address concerns related to specific patient populations, such as those with kidney disease.