A Randomized Clinical Trial of ICT-based Interventions for Sodium and Potassium Regulation in Healthy Adults.

Background: There is limited knowledge regarding effective strategies, including information and communication technology (ICT)-based interventions, to reduce sodium intake and increase potassium intake in healthy individuals.

Methods: We conducted a 3-month randomized controlled trial involving healthy adult employees with spot urine sodium-to-potassium ratios (spot UNa/UK) ≥4.0 or estimated 24-hour salt intake ≥10g. Estimated 24-hour UNa and UK were calculated using the Tanaka formula. Participants were assigned to one of four groups: (i) online education, where participants monitored their spot UNa/UK and received feedback from dieticians (n = 84); (ii) messaging, with similar self-monitoring and dietician messages (n = 84); (iii) self-learning, provided with an educational leaflet (n = 87); and (iv) a control group (n = 87). The primary outcome was the change in spot UNa/UK ratios, and secondary outcomes included changes in estimated 24-hour UNa and UK. The trial protocol specified a hierarchical order for testing the interventions, anticipating the highest efficacy in the online education group.

Results: After the intervention, the online education group showed a decrease in spot UNa/UK ratios (mean -0.9 (95% CI: -1.8 to 0.0), P = 0.052) compared to the control group. The increase in estimated 24-hour UK excretion was larger in online education compared to the control group (mean + 2.5 mmol/day (95% CI: -0.3 to 5.3), P = 0.085). The difference in estimated 24-hour UNa excretion between the online education and control groups was -4.3 mmol/day (95% CI: -15.5 to 6.9, P = 0.45).

Conclusions: Combining self-monitoring of sodium and potassium intake with ICT-based interventions, including online nutritional education, was associated with a modest reduction in the estimated ratios of sodium and potassium intake in healthy individuals.

Clinical Trial Registration: Japan Registry of Clinical Trials; 1032210217, https://jrct.niph.go.jp/en-latest-detail/jRCT1032210217.