Sodium and Potassium Intake in Healthy Adults in Thessaloniki Greater Metropolitan Area-The Salt Intake in Northern Greece (SING) Study

Abstract

A reduction in population sodium (as salt) consumption is a global health priority, as well as one of the most cost-effective strategies to reduce the burden of cardiovascular disease. High potassium intake is also recommended to reduce cardiovascular disease. To establish effective policies for setting targets and monitoring effectiveness within each country, the current level of consumption should be known. Greece lacks data on actual sodium and potassium intake. The aim of the present study was therefore to assess dietary salt (using sodium as biomarker) and potassium intakes in a sample of healthy adults in northern Greece, and to determine whether adherence to a Mediterranean diet is related to different sodium intakes or sodium-to-potassium ratio. A cross-sectional survey was carried out in the Thessaloniki greater metropolitan area (northern Greece) (n = 252, aged 18-75 years, 45.2% males). Participants' dietary sodium and potassium intakes were determined by 24-hour urinary sodium and potassium excretions. In addition, we estimated their adherence to Mediterranean diet by the use of an 11-item MedDietScore (range 0-55). The mean sodium excretion was 175 (SD 72) mmol/day, equivalent to 4220 (1745) mg of sodium or 10.7 (4.4) g of salt per day, and the potassium excretion was 65 (25) mmol/day, equivalent to 3303 (1247) mg per day. Men had higher sodium and potassium excretions compared to women. Only 5.6% of the sample had salt intake <5 g/day, which is the target intake recommended by the World Health Organization. Mean sodium-to-potassium excretion ratio was 2.82 (1.07). There was no significant difference in salt or potassium intake or their ratio across MedDietScore quartiles. No significant relationships were found between salt intake and adherence to a Mediterranean diet, suggesting that the perception of the health benefits of the Mediterranean diet does not hold when referring to salt consumption. These results suggest the need for a larger, nation-wide survey on salt intake in Greece and underline the importance of continuation of salt reduction initiatives in Greece.

Keywords: Greece; MedDietScore; intake; potassium; salt; sodium.

Figure 1

Distribution of single 24-hour salt intake estimates (see text for conversion of urinary excretions to estimates intakes).

Figure 2

Distribution of dietary sodium-to-potassium ratios (mg/mg) in the sample of 24-hour intake estimates (see text for conversion of urinary excretions to estimates intakes).