Reducing salt intake: a systematic review and meta-analysis of behavior change interventions in adults

CONTEXT: Prolonged high salt (sodium) intake can increase the risk of hypertension and cardiovascular disease. Behavioral interventions may help reduce sodium intake at the population level. OBJECTIVE: The effectiveness of behavior change interventions to reduce sodium intake in adults was investigated in this systematic review and meta-analysis. DATA SOURCE: The PubMed, Cochrane Library, Cumulative Index to Nursing and Allied Health Literature, and EMBASE databases were searched. DATA EXTRACTION: Narrative synthesis and random-effects meta-analyses were used to determine intervention efficacy. A total of 61 trials (46 controlled trials and 15 quasi-experimental studies) were included. RESULTS: Behavior change interventions resulted in significant improvements in salt consumption behavior (eg, decrease in purchase of salty foods; increase in use of salt substitutes), leading to reductions in sodium intake as measured by urinary sodium in 32 trials (N = 7840 participants; mean difference, –486.19 mg/d [95%CI, –669.44 to –302.95]; P < 0.001; I(2) = 92%) and dietary sodium in 19 trials (N = 3750 participants; mean difference –399.86 mg/d [95%CI, –581.51 to –218.20]; P < 0.001; I(2) = 96%), equivalent to a reduction of >1 g of salt intake daily. Effects were not significantly different based on baseline sodium intakes, blood pressure status, disease status, the use of behavior change theories, or the main method of intervention delivery (ie, online vs face-to-face). CONCLUSION: Behavior change interventions are effective at improving salt consumption practices and appear to reduce salt intake by >1 g/d. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no. CRD42020185639.