The question of whether reduced sodium intake is effective as a health prophylaxis initiative is unsolved. The purpose was to estimate the effects of low-sodium vs. high-sodium intake on blood pressure (BP), renin, aldosterone, catecholamines, and lipids.Methods
Studies randomizing persons to low-sodium and high-sodium diets evaluating at least one of the above outcome parameters were included. Data were analyzed with Review Manager 5.1.Results
A total of 167 studies were included. The effect of sodium reduction in: (i) Normotensives: Caucasians: systolic BP (SBP) −1.27mmHg (95% confidence interval (CI): −1.88, −0.66; P = 0.0001), diastolic BP (DBP) −0.05mmHg (95% CI: −0.51, 0.42; P = 0.85). Blacks: SBP −4.02mmHg (95% CI: −7.37, −0.68; P = 0.002), DBP −2.01 mm Hg (95% CI: −4.37, 0.35; P = 0.09). Asians: SBP −1.27mmHg (95% CI: −3.07, 0.54; P = 0.17), DBP −1.68mmHg (95% CI: −3.29, −0.06; P = 0.04). (ii) Hypertensives: Caucasians: SBP −5.48mmHg (95% CI: −6.53, −4.43; P < 0.00001), DBP −2.75mmHg (95% CI: −3.34, −2.17; P < 0.00001). Blacks: SBP −6.44mmHg (95% CI: −8.85, −4.03; P = 0.00001), DBP −2.40mmHg (95% CI: −4.68, −0.12; P = 0.04). Asians: SBP −10.21mmHg (95% CI: −16.98, −3.44; P = 0.003), DBP −2.60mmHg (95% CI: −4.03, −1.16; P = 0.0004). Sodium reduction resulted in significant increases in renin (P < 0.00001), aldosterone (P < 0.00001), noradrenaline (P < 0.00001), adrenaline (P < 0.0002), cholesterol (P < 0.001), and triglyceride (P < 0.0008).Conclusions
Sodium reduction resulted in a significant decrease in BP of 1% (normotensives), 3.5% (hypertensives), and a significant increase in plasma renin, plasma aldosterone, plasma adrenaline, and plasma noradrenaline, a 2.5% increase in cholesterol, and a 7% increase in triglyceride.Conclusions
This article is based on a Cochrane Review published in the Cochrane Database of Systematic Reviews (CDSR) 2011, Issue 11, DOI: 10.1002/14651858.CD004022.pub3 (see www.thecochranelibrary.com for information). Cochrane Reviews are regularly updated as new evidence emerges and in response to feedback, and the CDSR should be consulted for the most recent version of the review.