Inaccuracy of Self-reported Low Sodium Diet among Chinese: Findings from Baseline Survey for Shandong & Ministry of Health Action on Salt and Hypertension (SMASH) Project.

This study was aimed to evaluate the agreement between the self-reported sodium intake level and 24-h urine sodium excretion level in Chinese. The 24-h urine collection was conducted among 2112 adults aged 18-69 years randomly selected in Shandong Province, China. The subjects were asked whether their sodium intake was low, moderate, or high. The weighted kappa statistics was calculated to assess the agreement between 24-h urine sodium excretion level and self-reported sodium intake level. One third of the subjects reported low sodium intake level. About 70% of the subjects had mean 24-h sodium excretion>9 g/d, but reported low or moderate sodium intake. The agreement between self-reported sodium intake level and 24-h urine sodium excretion level was low in both normotensive subjects and hypertensive subjects. These findings suggested that many subjects who reported low sodium intake had actual urine sodium excretion>9 g/d. Sodium intake is often underestimated in both hypertensive and normotensive participants in China.

Estimating daily salt intake based on 24†h urinary sodium excretion in adults aged 18-69†years in Shandong, China.

OBJECTIVE: 24 h urinary sodium extretion was used to estimate the daily salt intake of shandong residents aged from 18 to 69 years in China. SETTING: 20 selected counties/districts in Shandong stratified by geographic region (Eastern, Central Southern and North Western) and residence type (urban vs rural). PARTICIPANTS: Among 2184 randomly selected adults, 2061 provided usable 24 h urine samples. Urine volume <500 mL or male creatinine <3.81 (female creatinine <4.57) are not included in the analysis. RESULTS: The mean sodium level excreted over 24 h was 237.61 mmol (95% CI 224.77 to 250.44) mmol. Overall, the estimated mean salt intake was 13.90 g/day (95% CI 13.15 to 14.65). The mean salt intake among rural residents was higher than that among urban residents (14.00 vs 13.68 g; p<0.01). Salt intake in men was higher than that in women (14.40 vs 13.37 g; p<0.01). Approximately 96% of the survey participants had a dietary salt intake of ≥6 g/day. CONCLUSIONS: The salt intake in Shandong is alarmingly higher than the current recommended amount (6 g/day). Thus, effective interventions to reduce salt intake levels to combat the increasing burden of non-communicable diseases need to be developed and implemented.

[Field observation on the effect of low-sodium and high-potassium salt substitute on blood pressure in the rural community-based population in China].

OBJECTIVE: To investigate the effect of commercial low-sodium and high-potassium salt substitutes on blood pressure in the rural community-based population in China. METHODS: We conducted a quasi-experiment on 411 adults, who were 30 to 60 years of age, in 2 rural communities from Laiwu city in Shandong province of China on data from blood pressure screening. The subjects were divided into 2 groups: high blood pressure (HBP) and non-HBP (NHBP). Both groups and their family members took a low-sodium and high-potassium salt substitute for 3 months to replace the normal salt in their bodies. Blood pressure (BP) and 24-hour urinary sodium and potassium were measured regularly in the 2 groups. RESULTS: There was a continuously decreasing trend for BP at the end of the first month. Three months later, the mean BP decreased by 7.4 mm Hg (1 mm Hg = 0.133 kPa, t = 10.096, P = 0.000) for SBP and 3.8 mm Hg (t = 8.017, P = 0.000) for DBP in the HBP group, when compared to a 1.2 mm Hg (t = 2.507, P = 0.007) decrease on SBP and 1.0 mm Hg (t = 2.987, P = 0.002) on DBP in the NHBP group. The mean urinary sodium had a decrease of 15.5 mmol/24 h (t = 1.803, P = 0.037), but the urinary potassium increased by 4.2 mmol/24 h (t' = 2.132, P = 0.018). The result of urinary sodium appeared to be as follows: potassium ratio (Na(+)/K(+)) decreased by 1.2 (t = 2.786, P = 0.003) in the HBP group. However, in NHBP group, the mean urinary sodium decreased by 1.7 mmol/24 h (t = 0.211, P = 0.417) and urinary potassium increased by 3.7 mmol/24 h (t' = 2.207, P = 0.015), together with the decrease of Na(+)/K(+) by 0.7 (t = 1.818, P = 0.036). CONCLUSION: Results from our study clearly demonstrated that the intake of low-sodium and high-potassium salt substitute could effectively reduce the BP with good compliance among adults in the rural community-based population in China. This was an effective but non-medical method to prevent and control the high blood pressure.