Sodium Reduction Program Incorporating Genetic Profile and an AI-Based App

Importance Excess salt intake is a major modifiable risk factor for hypertension and cardiovascular disease. Personalized interventions using genetic information and digital tools, such as smartphone applications, may enhance sodium reduction, but evidence remains limited. Objective To evaluate the effectiveness of a sodium reduction program incorporating a genetic profile and an artificial intelligence (AI)–based mobile app among adults with elevated blood pressure and a sodium-sensitive genotype. Design, Setting, and Participants A 3-arm randomized clinical trial, conducted at a Japanese electronics company from September 17 to December 16, 2024, included employees aged 20 to 65 years with elevated blood pressure and the sodium-sensitive AGT M235T genotype. Interventions Participants were randomized on a 1:1:0.2 basis to (1) a treatment group receiving a genetic profile and an AI-based app incorporating sodium-specific information; (2) a control group receiving no intervention; or (3) an app-only group using the app without a genetic profile or information. Main Outcomes and Measures The primary outcome was daily salt intake, estimated from spot urine samples using the INTERSALT (International Study of Electrolyte Excretion and Blood Pressure) formula. Secondary outcomes included self-reported body mass index, behavior change intentions, and systolic and diastolic blood pressure. Analysis was performed on an intention-to-treat basis. Results Of 312 randomized participants, 289 completed follow-up (mean [SD] age, 51.3 [8.3] years; 252 of 279 men [90.3%]). The mean (SD) baseline salt intake was 11.3 (2.0) g/d. At 3 months, no significant difference in salt intake was observed between the treatment and control groups (mean difference, −0.2 g/d; 95% CI, −0.7 to 0.3 g/d) or between the treatment and app-only groups (mean difference, −0.04 g/d; 95% CI, −0.9 to 0.8 g/d). No significant differences were observed between groups in any secondary outcomes. Conclusions and Relevance In this randomized clinical trial conducted among individuals with elevated blood pressure and a sodium-sensitive genotype, a sodium reduction program combining a genetic profile and an AI-based app with sodium-specific information did not significantly reduce salt intake. These findings highlight the challenges of achieving dietary behavior change through genetic personalized plus digital interventions. Trial Registration http://umin.ac.jp/ctr Identifier: UMIN000052685