Potassium chloride 0.15% (potassium 20mmol/1litre) / Magnesium chloride 0.2% (magnesium 10mmol/1litre) / Sodium chloride 0.9% infusion 1litre bags

BackgroundHypertension is a major risk factor for cardiovascular disease. Salt substitutes may reduce sodium intake while maintaining palatability, but comparative effects across formulations remain uncertain.MethodsWe conducted a systematic review and frequentist random-effects network meta-analysis of randomised controlled trials in adults comparing salt substitutes with regular salt, other substitutes or no intervention. Databases (PubMed, Embase, CENTRAL, CNKI, Wanfang), WHO-ICTRP and ClinicalTrials.gov were searched from inception to Oct 3, 2025 (PROSPERO CRD42023451859). We assessed the risk of bias using a modified Cochrane tool and conducted a random-effects network meta-analysis, with evidence certainty evaluated through the GRADE approach.ResultsWe included 34 randomised controlled trials involving 37,063 participants across 15 countries (17 from China, 17 from other countries; mean age 62.3 years). Our results indicate that moderate-potassium and low-sodium salt substitutes (25-40% KCl, 60-79% NaCl) probably reduce all-cause mortality, cardiovascular mortality, non-fatal cardiovascular events and systolic blood pressure (SBP) compared to regular salt, with reductions of 7-17 deaths per 1000 individuals and 4.39-4.64 mmHg for SBP, based on moderate to high certainty evidence. Mortality and cardiovascular benefits are predominantly driven by one large Chinese trial (SSaSS, n = 20,995); excluding this trial eliminated statistical significance for all-cause mortality. Among non-Chinese studies, none contributed mortality data. Substitutes with higher potassium or very low sodium showed similar blood pressure reductions but provided less certain evidence regarding mortality and events. No substitute increased adverse events or withdrawals, and acceptability was comparable to regular salt.ConclusionsSalt substitutes, particularly moderate-potassium and low-sodium formulations, represent a promising sodium reduction strategy. However, current evidence for mortality and cardiovascular event benefits is dominated by one large Chinese trial and has very limited generalisability beyond Chinese populations with high discretionary salt use. These products appear acceptable and safe in people without renal impairment, but clinicians should rule out kidney disease and hyperkalaemia risk before recommending them, and large trials in non-Chinese populations are needed.

Abstract licence: CC BY-NC-ND

Despite consistent evidence of the cardioprotective benefits of reduced-sodium salt, it remains an underutilised intervention. Understanding how reduced-sodium salt is perceived is required to scale-up its use. This review summarises end user and healthcare professional knowledge, attitudes, and behaviours about reduced-sodium salt. We systematically searched four databases (inception to February 2024) and identified studies reporting knowledge, attitudes and behaviours towards reduced-sodium salt. Twenty-nine studies from 11 countries were included, 18 of which were intervention studies involving reduced-sodium salt and 11 were descriptive studies examining perceptions among the general community and healthcare professionals. Among intervention studies, there was high overall acceptability but mixed findings on taste. Outcomes related to use or willingness to use were mostly positive especially following cost-subsidisation. Among descriptive studies, there was low awareness (ranging from 0-32%) and reported use (10-16%) of reduced-sodium salt among the general community. Barriers to use included low availability and higher costs compared to regular salt. Awareness was higher among healthcare professionals (71%). Overall, most studies found high acceptability and willingness to use following exposure to reduced-sodium salt, despite some detecting taste differences. Greater awareness coupled with strategies to improve availability and affordability are important to scale-up the use of reduced-sodium salt.

Abstract licence: CC BY

BackgroundTemporomandibular disorders (TMDs) are a major cause of chronic orofacial pain, with myalgia of the masticatory muscles being central to symptom burden. Electrolyte modulation, particularly magnesium, may influence neuromuscular excitability and nociceptor sensitization, but no systematic review has synthesized the evidence for muscle pain syndromes or its relevance to TMD.ObjectivesTo evaluate the efficacy of electrolyte supplementation (magnesium, sodium, calcium, and potassium) in reducing muscle cramps and myalgia, and to explore the biological plausibility and potential extrapolation to TMD-related myofascial pain.MethodsThis systematic review followed PRISMA guidelines and was prospectively registered in PROSPERO (CRD420251120631). PubMed/MEDLINE, Embase, and Cochrane CENTRAL were searched from January 1995 to August 2025. Randomized or quasi-randomized trials of electrolyte supplementation for cramps or myalgia were eligible. Data extraction and risk-of-bias assessment (RoB 2 tool) were performed independently by 2 reviewers. Meta-analyses used random-effects models in R (v4.4.3) and Python (v3.11).ResultsThirteen trials were included. Magnesium was most frequently studied (10 RCTs). In pregnancy-associated cramps (4 trials, N≈364), magnesium significantly reduced cramp frequency compared with placebo (pooled RR 1.35, 95% CI: 1.05-1.74, P = .02). In nocturnal or persistent leg cramps in adults (4 trials, N≈396), no significant effect was found (MD -0.42 cramps/week, 95% CI: -1.15 to 0.31, P = .26). Intravenous magnesium showed no benefit in older adults, but a perioperative trial demonstrated reduced fasciculations and postoperative myalgia. Sodium-based solutions reduced cramp susceptibility in exercise and cirrhosis, while calcium and potassium lacked supportive evidence. Risk of bias was generally low to moderate.ConclusionMagnesium supplementation benefits pregnancy-related cramps but shows inconsistent effects in other populations. Sodium-based interventions are context-specific, and calcium and potassium remain unsupported. Magnesium is the most plausible candidate for translation to TMD myalgia, warranting targeted clinical trials.

Abstract licence: CC BY-NC-ND