Effect of lower sodium intake on health: systematic review and meta-analyses

Abstract

Objective To assess the effect of decreased sodium intake on blood pressure, related cardiovascular diseases, and potential adverse effects such as changes in blood lipids, catecholamine levels, and renal function.Design Systematic review and meta-analysis.Data sources Cochrane Central Register of Controlled Trials, Medline, Embase, WHO International Clinical Trials Registry Platform, the Latin American and Caribbean health science literature database, and the reference lists of previous reviews.Study selection Randomised controlled trials and prospective cohort studies in non-acutely ill adults and children assessing the relations between sodium intake and blood pressure, renal function, blood lipids, and catecholamine levels, and in non-acutely ill adults all cause mortality, cardiovascular disease, stroke, and coronary heart disease.Study appraisal and synthesis Potential studies were screened independently and in duplicate and study characteristics and outcomes extracted. When possible we conducted a meta-analysis to estimate the effect of lower sodium intake using the inverse variance method and a random effects model. We present results as mean differences or risk ratios, with 95% confidence intervals.Results We included 14 cohort studies and five randomised controlled trials reporting all cause mortality, cardiovascular disease, stroke, or coronary heart disease; and 37 randomised controlled trials measuring blood pressure, renal function, blood lipids, and catecholamine levels in adults. Nine controlled trials and one cohort study in children reporting on blood pressure were also included. In adults a reduction in sodium intake significantly reduced resting systolic blood pressure by 3.39 mm Hg (95% confidence interval 2.46 to 4.31) and resting diastolic blood pressure by 1.54 mm Hg (0.98 to 2.11). When sodium intake was <2 g/day versus ≥2 g/day, systolic blood pressure was reduced by 3.47 mm Hg (0.76 to 6.18) and diastolic blood pressure by 1.81 mm Hg (0.54 to 3.08). Decreased sodium intake had no significant adverse effect on blood lipids, catecholamine levels, or renal function in adults (P>0.05). There were insufficient randomised controlled trials to assess the effects of reduced sodium intake on mortality and morbidity. The associations in cohort studies between sodium intake and all cause mortality, incident fatal and non-fatal cardiovascular disease, and coronary heart disease were non-significant (P>0.05). Increased sodium intake was associated with an increased risk of stroke (risk ratio 1.24, 95% confidence interval 1.08 to 1.43), stroke mortality (1.63, 1.27 to 2.10), and coronary heart disease mortality (1.32, 1.13 to 1.53). In children, a reduction in sodium intake significantly reduced systolic blood pressure by 0.84 mm Hg (0.25 to 1.43) and diastolic blood pressure by 0.87 mm Hg (0.14 to 1.60).Conclusions High quality evidence in non-acutely ill adults shows that reduced sodium intake reduces blood pressure and has no adverse effect on blood lipids, catecholamine levels, or renal function,...

Review ArticleCurrent salt reduction policies across gradients of inequality-adjusted human development in the WHO European region: minding the gaps

“…Furthermore, evidence supports the positive impact of reduced salt consumption in a corresponding reduction in blood pressure (8,9) . Given the elevated levels at which salt is consumed in the WHO European Region, centrally implemented national salt reduction strategies represent a highly cost-effective tool to reduce CVD risk and tackle the growing burden of NCD (10)(11)(12)(13) .…”

Sodium intake status in United States and potential reduction modeling: an NHANES 2007–2010 analysis

“…2009; USDA 2010b, 2015; Aburto et al. 2013; Institute of Medicine 2013), and other consequent health outcomes, including coronary heart disease (CHD), stroke, and mortality. Our data show that despite consistent recommendations from government, scientific and public health agencies to limit sodium intake, sodium intake among the US population has not changed in the past decade and has remained consistently higher than recommendation for all age or gender groups.…”

“…Reduced sodium intake has been demonstrated to reduce blood pressure and is also associated with a reduced risk of stroke and fatal CHD in adults (He and MacGregor 2002; Aburto et al. 2013; He et al. 2014).…”

“…2009; USDA 2010b, 2015; Aburto et al. 2013; Institute of Medicine 2013). Nearly 1 in 3 Americans or 68 million adults have hypertension, half of whom have uncontrolled hypertension (Gillespie et al.…”

Evaluation of actions, barriers, and facilitators to reducing dietary sodium in health care institutions

“…Excess sodium consumption causes hypertension and is a major modifiable risk factor for cardiovascular disease and stroke (Aburto et al., 2013). In Canada, the average daily intake of sodium is almost double the daily adequate intake (AI) of 1,500 mg/day and well above the tolerable upper intake level (UL) of 2,300 mg/day (Health Canada, 2018; Institute of Medicine, 2005).…”