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.

Effect of dietary salt restriction on central blood pressure: A systematic review and meta‐analysis of the intervention studies

“…As the habitual salt intake in most countries in the world is close to 10 g per day, 55‐58 an average reduction of 60% per day, as in our meta‐analysis, would lead to the achievement of the recommended target of 5 g or lower per day for the population 55 : this observation suggests that the results of our study could be applicable to real life conditions and are relevant to population‐based strategies for reduction of salt intake 59 …”

Urinary Potassium Excretion and Progression of CKD

“…In line with this notion, previous studies have shown more protein and sodium intake in men than in women (44,45). Moreover, a recent study showed that there was a considerable variation in potassium intake between men and women among 252 healthy Greek adults (46). Notably, a previous study suggested a possible role of estrogen in the lower plasma potassium level in female rodents (47).…”

Joint association of urinary sodium and potassium excretion with cardiovascular events and mortality: prospective cohort study

“…While small phase II clinical trials, such as DASH-Sodium,40 have achieved these targets in the short term, they required complete control of dietary intake, which is impractical in free living populations. In contrast, the PREDIMED study,43 which promoted increased intake of potassium containing foods (fruit, vegetables, nuts) with greater adherence to the Mediterranean diet, without focusing on low sodium intake, reported a statistically significant reduction in cardiovascular disease and mortality, and adherence to a Mediterranean diet has an inconsistent correlation with sodium intake 4445. In addition, a recent analysis of the NHANES study reported that sodium intake >2.3 g/day was associated with better diet quality, compared with diets of less than 2.3 g/day, meaning that improving dietary quality is likely to be easier to achieve within a moderate sodium intake range 46.…”