Blood Pressure Reduction Effects of Salt Substitutes in Different Application Settings A Meta-Analysis of Randomized...

Meta-analysis has been performed on the blood pressure-lowering effect of salt substitutes; however, whether the effects vary by application setting remains unclear.

This study aims to compare the blood pressure-lowering effect of salt substitution between home-cooking and collective-cooking settings.

We searched PubMed, EMBASE, the Cochrane Library, CNKI, and WanFang databases for randomized controlled trials (RCTs) comparing salt substitutes with usual salt on blood pressure, with the last search on June 3-4, 2025. Meta-analysis stratified by application setting was performed.

Participants (N = 29,570) in 21 RCTs (n = 27,813 participants in 18 RCTs with home-cooking and n = 1,757 participants in 3 RCTs with collective-cooking) were included for analysis. Salt substitutes significantly reduced systolic blood pressure (SBP) by 4.7 mm Hg (95% CI: -5.7 to -3.6; I² = 65.3%) and diastolic blood pressure (DBP) by 1.4 mm Hg (95% CI: -1.7 to -1.0; I² = 17.3%) compared to usual salt. The effect varied by application setting: in home-cooking, SBP and DBP were reduced by 4.2 mm Hg (95% CI: -5.3 to -3.2; I² = 61.5%) and 1.2 mm Hg (95% CI: -1.6 to -0.9; I² = 14.4%), respectively; in collective-cooking, reductions were substantially larger - 7.7 mm Hg (95% CI: -10.0 to -5.3; I² = 0%) and 2.4 mm Hg (95% CI: -3.8 to -1.1; I² = 0%), respectively. The between-setting difference was significant for SBP (P = 0.008) and borderline significant for DBP (P = 0.099). Sensitivity analyses restricted to high-quality studies or other study subsets, as well as meta-regression adjusting for multiple variables, generally supported these findings.

Replacing usual salt with salt substitutes lowered blood pressure more in the collective-cooking than the home-cooking setting, suggesting that public health policies and strategies should be developed to prioritize full adoption of salt substitutes to maximize its health benefits.