Sodium, Potassium and Iodine Intake, in A National Adult Population Sample of the Republic of Moldova

Population-level salt intake in the WHO European Region in 2022: a systematic review

OBJECTIVE

The WHO recommends that adults consume less than 5 g of salt per day to reduce the risk of CVD. This study aims to examine the average population daily salt intake in the fifty-three Member States of the WHO European Region.

DESIGN

A systematic review was conducted to examine the most up-to-date salt intake data for adults published between 2000 and 2022. Data were obtained from peer-reviewed and grey literature, WHO surveys and studies, as well as from national and global experts.

SETTING

The fifty-three Member States of the WHO European Region.

PARTICIPANTS

People aged 12 years or more.

RESULTS

We identified fifty studies published between 2010 and 2021. Most countries in the WHO European Region (n 52, 98 %) reported salt intake above WHO recommended maximum levels. In almost all countries (n 52, 98 %), men consume more salt than women, ranging between 5·39 and 18·51 g for men and 4·27 and 16·14 g for women. Generally, Western and Northern European countries have the lowest average salt intake, whilst Eastern European and Central Asian countries have the highest average. Forty-two percentage of the fifty-three countries (n 22) measured salt intake using 24 h urinary collection, considered the gold standard method.

CONCLUSIONS

This study found that salt intakes in the WHO European Region are significantly above WHO recommended levels. Most Member States of the Region have conducted some form of population salt intake. However, methodologies to estimate salt intake are highly disparate and underestimations are very likely.

Sodium and potassium consumption in Jamaica: National estimates and associated factors from the Jamaica Health and Lifestyle Survey 2016-2017

This study aimed to estimate dietary sodium and potassium consumption among Jamaicans and evaluate associations with sociodemographic and clinical characteristics. A cross-sectional study was conducted using data from the Jamaica Health and Lifestyle Survey 2016-2017. Participants were noninstitutionalized Jamaicans aged ≥15 years. Trained staff collected sociodemographic and health data via interviewer-administered questionnaires and spot urine samples. The Pan American Health Organization formula was used to estimate 24-hour urine sodium and potassium excretion. High sodium level was defined as ≥2000 mg/day, and low potassium levels as <3510 mg/day (World Health Organization criteria). Associations between these outcomes and sociodemographic and clinical characteristics were explored using multivariable ANOVA models using log-transformed 24-hour urine sodium and potassium as outcome variables. Analyses included 1009 participants (368 males, 641 females; mean age 48.5 years). The mean sodium excretion was 3582 mg/day (males 3943 mg/day, females 3245 mg/day, P < .001). The mean potassium excretion was 2052 mg/day (males, 2210 mg/day; females, 1904 mg/day; P = .001). The prevalence of high sodium consumption was 66.6% (males 72.8%, females 60.7%, P < .001) and that of low potassium intake was 88.8% (85.1% males, 92.3% females, P < .001). Sodium consumption was inversely associated with older age, higher education, and low glomerular filtration rate but was directly associated with being male, current smoking, and obesity. Overall, males had higher sodium consumption than women, with the effect being larger among hypertensive men. Women with hypertension had lower sodium consumption than nonhypertensive women; however, hypertensive men had higher sodium consumption than nonhypertensive men. Potassium consumption was higher among men, persons with obesity, and those with high total cholesterol but was lower among men with "more than high school" education compared to men with "less than high school" education. We conclude that most Jamaican adults have diets high in sodium and low in potassium. In this study, sodium consumption was directly associated with male sex, obesity, and current smoking but was inversely associated with older age and higher education. High potassium consumption was associated with obesity and high cholesterol levels. These associations should be further explored in longitudinal studies and population-based strategies should be developed to address these cardiovascular risk factors.

Strengthening the strategy to sustain optimal iodine status in the Republic of Moldova: Assessing the use of iodized salt in industrially processed foods

BACKGROUND

Although national legislation in the Republic of Moldova includes the use of iodized salt in processed food industry as well as household (cooking and table) salt, little is known of the actual use of iodized salt in the food industry and its contribution to the overall iodine intake of the population. This study has helped to address the gap in understanding about how much iodized salt is used in the production of different foods and to identify where more information is still required in order to more fully characterize the contribution of food industry salt to population iodine intake.

METHODS

Using the available food consumption and production data, the assessment introduces a novel modelling technique, based on the methodology of the IGN Programme Guidance to assess the use of iodized salt in industrially produced foods (IPF). The method included the identification of key salt containing IPF and modelling of the salt and potential iodine intake in two groups of the population, non-pregnant adults and pregnant women. The findings were synthetized to develop a list of recommendations for adjustment or strengthening the existing salt iodization strategy.

MAIN RESULTS

In RM, the salt used for industrially produced bread and household use provide almost 80% of all salt intake for adults. The intake from iodized salt at household level and the 8 key salt- containing IPF is estimated to currently meet 89% and 53% of the recommended nutrient for adults and pregnant women, respectively. If all salt used at household level and industrial bread baking would be iodized, then, potentially, it could ensure 181% and 109%, respectively, of the required iodine intake.

CONCLUSIONS

Use of iodized salt in the processed food industry is of growing significance and universal use of iodized salt at household level and in bread production could result in a desirable increase in iodine intake. The national salt iodization strategy should include strengthened regulatory monitoring of iodized salt use in the bread baking industry.

Low Potassium Intake: A Common Risk Factor for Nephrolithiasis in Patients with High Blood Pressure

Hypertension (Htn) is a crucial cause of cardio-vascular and chronic kidney disease. Moreover, it is an independent risk factor for nephrolithiasis (NL). A diet rich in vegetables and fruits is indicated for both Htn and NL prevention, and the 24-h urinary potassium excretion can be used as a warning light for adherence. The aim of this study is to demonstrate the association between urinary potassium excretion and recurrent nephrolithiasis among patients affected by Htn. We have analyzed medical records of 119 patients affected by Htn and NL (SF-Hs) referring to Bone and Mineral Metabolism laboratory and 119 patients affected by Htn but without NL (nSF-Hs) referring to Hypertension and Organ Damage Hypertension related laboratory, both in Federico II University of Naples. The potassium 24-h urinary levels in SF-Hs were significantly lower compared to nSF-Hs. This difference was confirmed by the multivariable linear regression analysis in the unadjusted model and adjusted model for age, gender, metabolic syndrome, and body mass index. In conclusion, a higher potassium urinary excretion in 24-h is a protective factor against NL in patients affected by Htn and dietary interventions can be considered for kidney protection.

Dietary Potassium Intake and Risk of Diabetes: A Systematic Review and Meta-Analysis of Prospective Studies

(1) Background: Dietary potassium intake is positively associated with reduction of cardiovascular risk. Several data are available on the relationship between dietary potassium intake, diabetes risk and glucose metabolism, but with inconsistent results. Therefore, we performed a meta-analysis of the prospective studies that explored the effect of dietary potassium intake on the risk of diabetes to overcome these limitations. (2) Methods: A random-effects dose-response meta-analysis was carried out for prospective studies. A potential non-linear relation was investigated using restricted cubic splines. (3) Results: A total of seven prospective studies met the inclusion criteria. Dose-response analysis detected a non-linear relationship between dietary potassium intake and diabetes risk, with significant inverse association starting from 2900 mg/day by questionnaire and between 2000 and 5000 mg/day by urinary excretion. There was high heterogeneity among studies, but no evidence of publication bias was found. (4) Conclusions: The results of this meta-analysis indicate that habitual dietary potassium consumption is associated with risk of diabetes by a non-linear dose-response relationship. The beneficial threshold found supports the campaigns in favour of an increase in dietary potassium intake to reduce the risk of morbidity and mortality. Further studies should be carried out to explore this topic.

Sodium, Potassium and Iodine Intake in an Adult Population of Lithuania

Hypertension is a leading risk factor for cardiovascular events and death. A reduction in salt intake is among the most cost-effective strategies to reduce blood pressure and the risk of cardiovascular diseases. Increasing potassium lowers blood pressure and is associated with lower cardiovascular risk. Adequate iodine intake is important to prevent iodine deficiency disorders. Salt iodization is a key strategy to prevent such deficiency. In Lithuania, no surveys have been performed to directly assess sodium, potassium and iodine consumption. The aim of the present study was to measure sodium, potassium and iodine intake in a randomly selected adult Lithuanian adult population using 24 h urine collections, and to assess knowledge, attitudes and behavior towards salt consumption. Salt and potassium intakes were estimated in 888 randomly selected participants by 24 h urine sodium and potassium excretion and 679 individuals provided suitable 24 h urine samples for the analysis of iodine excretion. Average salt intake was 10.0 (SD 5.3) g/24 h and average potassium intake was 3.3 (SD 1.3) g/24 h. Only 12.5% of participants consumed less than 5 g/24 h of salt. The median value of urinary iodine concentration (UIC) was 95.5 μg/L. Our study showed that average salt intake is twice as high as the maximum level recommended by the World Health Organization while potassium and iodine intakes in Lithuania are below the recommended levels.

Urinary iodine and sodium concentration and thyroid status in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

OBJECTIVES

To evaluate urinary iodine concentration (UIC) in civil servants aged 35-74 years of the Brazilian Study of Adults Health (ELSA-Brasil) to analyze its relationship with sociodemographic, clinical risk factors, lifestyle, urinary Na and thyroid status.

DESIGN

Cross-sectional study in six Brazilian cities.

METHODS

This analysis included 792 participants with information about urinary iodine concentration (UIC). Thyroid status was defined by serum levels of TSH/FT4 and the current use of antithyroid drugs for treatment of overt hyperthyroidism or levothyroxine to treat overt hypothyroidism. The determination of UIC was carried out with an inductively coupled plasma mass spectrometer (ICP-MS) and was expressed as median with Interquartile Range (IQR).

RESULTS

In 792 participants, thereof 52% women, mean age was 51.9 (9.0) years. The median UIC was 219 (IQR, 166-291) for all persons studied, thereof 211 (IQR, 157-276) for women and 231 (IQR, 178-304) for men. According to the WHO classification, for all persons studied, 60% had more than adequate iodine-supply (UIC ≥200 μg/L), 37% were adequately supplied (UIC 100-199 μg/L) and <3% had a deficient iodine status (<100 μg/L). In the 35-44-year age strata, which includes women of childbearing age, 23.2% of women presented less than 150 μg/L of UIC. No differences in UIC were detected according to thyroid status. (P = 0.39) The correlation between Ur-Na and UIC showed a Spearman coefficient of 0.52 (P < 0.0001) and it was also found an association of Ur-Na with UIC: Beta of 1.76 (95% Confidence Interval (95% CI): 1.01 to 2.51. The urinary Na concentration showed a synergy with the UIC, that means medians of 57, 72, 107 and 141 mmol Na/L urine (P < 0.001) in the groups with the four UIC classes according to the WHO grading mentioned above. The very low Na content in the persons exhibiting <100 μg/L UIC seems to reflect also a higher urine volume due to the frequent use of diuretics. The strong relationship between the urinary Na concentration and the UIC points to a dependence of the UIC on the individual consumption of iodized salt, which should be more considered in future studies. The strong relationship between the urinary Na concentration and the UIC points to a dependence of the UIC on the individual consumption of iodized salt, which should be more considered in future studies.

CONCLUSIONS

Euthyroid persons were dominating by more than four fifths and no significant association was found between UIC and thyroid status. Although most of the persons studied present more than adequate iodine intake it was observed that nearly a quarter of women in childbearing age are iodine deficient.

Trend in potassium intake and Na/K ratio in the Italian adult population between the 2008 and 2018 CUORE project surveys

BACKGROUND AND AIMS

Low potassium intake, in addition to high sodium, has been associated with higher risk of hypertension and CVD. The Study assessed habitual potassium intake and sodium/potassium ratio of the Italian adult population from 2008 to 2012 to 2018-2019 based on 24-h urine collection, in the framework of the CUORE Project/MINISAL-GIRCSI/MENO SALE PIU' SALUTE national surveys.

METHODS AND RESULTS

Data were from cross-sectional surveys of randomly selected age-and-sex stratified samples of resident persons aged 35-74 years in 10 (out of 20) Italian regions. Urinary electrolyte and creatinine measurements were performed in a central laboratory. Analyses considered 942 men and 916 women, examined in 2008-2012, and 967 men and 1010 women, examined in 2018-2019. In 2008-2012, the age-standardized mean of potassium intake (urinary potassium accounts for 70% of potassium intake) was 3147 mg (95% CI 3086-3208) in men and 2784 mg (2727-2841) in women, whereas in 2018-2019, it was 3043 mg (2968-3118) and 2561 mg (2508-2614) respectively. In 2008-2012, age-adjusted prevalence of persons with an adequate potassium intake (i.e. ≥ 3510 mg/day) was 31% (95% CI 28-34%) for men and 18% (16-21%) for women; in 2018-2019, it was 26% (23-29%) and 12% (10-14%) respectively. The sodium/potassium ratio significantly decreased both in men and women.

CONCLUSIONS

The average daily potassium intake of the Italian general adult population remains lower than the WHO and EFSA recommended level. These results suggest the need of a revision to strengthen initiatives for the promotion of an adequate potassium intake at the population level.

Association Between AGT M235T and Left Ventricular Mass in Vietnamese Patients Diagnosed With Essential Hypertension

Background: Increasing left ventricular mass in hypertensive patients is an independent prognostic marker for adverse cardiovascular outcomes. Genetic factors have been shown to critically affect left ventricular mass. AGT M235T is one of the genetic polymorphisms that may influence left ventricular mass due to its pivotal role in the regulation of plasma angiotensinogen level as well as hypertension pathophysiology in Asian populations. Currently, how M235T affects left ventricular mass is not well-described in Vietnamese hypertensive patients. This study aimed to investigate the association between M235T and left ventricular mass in Vietnamese patients diagnosed with essential hypertension.

Materials and Methods:AGT M235T genotyping and 2D echocardiography were performed on 187 Vietnamese subjects with essential hypertension. All the ultrasound parameters were obtained to calculate the left ventricular mass index according to the American Society of Echocardiography and the European Association of Cardiovascular Imaging 2015 guidelines. Other clinical characteristics were also recorded, including age, gender, duration of hypertension, hypertensive treatment, lifestyle, renal function, fasting plasma glucose, and lipid profile.

Results: MT and TT genotypes were determined in 30 and 157 subjects, respectively. AGT M235T genotype, duration of hypertension, body mass index, and ejection fraction statistically affected the left ventricular mass index, which was significantly greater in TT compared to MT carriers after adjusting for confounding factors.

Conclusion: The TT genotype of AGT M23T was associated with greater left ventricular mass in Vietnamese patients diagnosed with essential hypertension.

National survey to estimate sodium and potassium intake and knowledge attitudes and behaviours towards salt consumption of adults in the Sultanate of Oman

OBJECTIVES

To estimate population sodium and potassium intakes and explore knowledge, attitudes and behaviour (KAB) towards the use of salt in adults in the Sultanate of Oman.

DESIGN

National cross-sectional population-based survey.

SETTING

Proportional random samples, representative of Omani adults (18 years or older), were obtained from all governorates of the Sultanate of Oman.

PARTICIPANTS

Five hundred and sixty-nine (193 men, 376 women; 18 years or older) were included in the analysis (response rate 57%). Mean age was 39.4 years (SD 13.1). Participants attended a screening including demographic, anthropometric and physical measurements.

PRIMARY AND SECONDARY OUTCOME MEASURES

We assessed dietary sodium, potassium and creatinine by 24-hour urinary sodium (UNa), potassium (UK) and creatinine (UCr) excretions. We collected KAB by a questionnaire on an electronic tablet.

RESULTS

Mean UNa was 144.3 (78.8) mmol/day, equivalent to 9.0 g of salt/day and potassium excretion 52.6 (32.6) mmol/day, equivalent to 2.36 g/day, after adjusting for non-urinary losses. Men ate significantly more sodium and potassium than women. Only 22% of the sample had a salt intake below the WHO recommended target of 5 g/day and less than 10% met WHO targets for potassium excretion (>90 mmol/day). While 89.1% of those interviewed knew that consuming too much salt could cause serious health problems and only 6.9% felt they were using too much added salt, one in two participants used always or often salt, salty seasonings or salty sauces in cooking or when preparing food at home.

CONCLUSIONS

In the Sultanate of Oman, salt consumption is higher and potassium consumption lower than recommended by WHO, both in men and in women. The present data provide, for the first time, evidence to support a national programme of population salt reduction to prevent the increasing burden of cardiovascular disease in the area.