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Survival requires regulation of water and salt content. Loss of fluid from cellular or extracellular triggers drinking. However, a palatable taste can override homeostasis. A satiety signal is generated by oral and gastric factors in combination with absorption from the gut. Specialized cells in the brain (‘osmoreceptors’) detect hydration of the extracellular fluid. Other receptors are sensitive to blood volume. In addition to incentive motivation, there appears to be a negative reinforcement from the aversiveness of dehydration. Feeding and drinking interact. Dehydration causes a reduction in the amount of food ingested. Food intake can influence water intake. If hungry but not thirsty rats are given small food pellets at, say, every 90 seconds, they drink very large amounts of fluid: ‘schedule-induced polydipsia’. Sodium appetite is associated with hedonic hotspots. Potassium appetite relies upon a learned association between the taste of a food and restoration of potassium levels.
High dietary sodium (Na) intake is strongly linked to hypertension, cardiovascular disease, and premature mortality. As part of global efforts to reduce salt consumption, potassium chloride (KCl) has emerged as a promising salt substitute due to its salty taste at low concentrations(1). Bread, a major dietary sodium source in New Zealand, contributes approximately 18% of total sodium intake in the national diet(2). Therefore, reformulation strategies that effectively reduce sodium while maintaining bread quality attributes are essential for consumer acceptance and real-world implementation. This study aimed to investigate the effect of potassium-enriched, reduced-sodium salt on white bread quality, specifically in terms of volume, moisture, colour, texture and mineral content. White bread was prepared using a standardised base formulation, in which table salt (NaCl) was replaced with 0%, 25%, 50%, 75%, and 100% KCl, respectively. All samples were processed under identical conditions, and key quality parameters were assessed using standardised testing methods. Inductively Coupled Plasma (ICP) was used to confirm the content of sodium and potassium in bread samples at different substitution levels. One-way analysis of variance (ANOVA) was used to assess differences in bread quality across formulations, followed by post-hoc Tukey Honestly Significant Difference tests (α = 0.05). Bread volume and moisture content showed no significant differences across substitution levels. Based on Texture Profile Analysis, instrumental hardness measurements slightly increased with higher KCl substitution, while gumminess rose mildly and other texture parameters remained stable. Instrumental colour measurements indicated that both crust and crumb colour remained consistent across all formulations. Overall, these findings support the practical application of using potassium-enriched, reduced-sodium salt in bread formulation without compromising bread quality and its potential to contribute meaningfully to population-level sodium reduction and improved public health outcomes.
Adults in Aotearoa New Zealand (NZ) consume 3,386 mg of sodium per day(1), 40% more than the 2,000 mg per day recommended by the World Health Organization (WHO) for lowering blood pressure and reducing risk of stroke, heart disease, and gastric cancer(2). Packaged and processed foods are the main source of dietary sodium in NZ, with bread, a major staple food, being the single largest contributor. Initiatives to reduce the sodium content of NZ breads include: the Heart Foundation (HF) food reformulation programme which sets sodium reduction targets and works with food companies to meet them; the Australasian Health Star Rating front-of-pack nutrition label which encourages reformulation by bread companies; and the global WHO sodium reduction benchmarks. However, there is no recent objective evidence examining the impact of these voluntary initiatives on sodium in the NZ packaged bread supply. Our aim was to compare the mean sodium content of NZ packaged breads in 2013 and 2023 and assess their compliance with the NZ HF and WHO sodium reduction benchmarks. Sodium data for each year were obtained from the Nutritrack supermarket food composition database. Mean differences between years were assessed using independent samples t-tests and chi-square tests. A sensitivity analysis was also completed, including only breads available for sale in both years, thus investigating potential reformulation. There was a significant reduction in the mean sodium content of all bread from 2013 (n=345) to 2023 (n=309) of 46 mg/100g (p <0.001). There was also a significant reduction in the sodium content of 90 identical breads available for sale in both years, from a mean (SD) of 422 (120) mg/100g in 2013 to 384 (97) mg/100g in 2023 (p<0.001). In 2013, 20% (n=70/345) of breads met the HF benchmarks, and 10% (33/345) met the WHO benchmarks; corresponding values for 2023 were 45% (n=138/309) and 18% (n=57/309) (p <0.001 for both). If continued, the modest reduction in sodium content and increase in the percentage of NZ breads meeting relevant sodium reduction benchmarks could positively affect public health, particularly if extended across the packaged food supply.
A high sodium intake is a major risk factor for raised blood pressure. Consumption of fish fillet is associated with lower blood pressure in humans and other animals, whereas the effects of consuming fish residuals are less explored. To obtain high-quality fishmeal with acceptable sensory properties, the fish residuals may be washed with seawater onboard factory trawlers. This will increase the sodium content in the residuals, and whether this affects blood pressure has not yet been investigated. The primary objective of the present study was to investigate if the increased sodium content in Atlantic cod (Gadus morhua) residuals after washing with saltwater affected the development of high blood pressure in male obese Zucker fa/fa rats which spontaneously develop hypertension. Rats were fed diets containing cod protein powders prepared from unwashed or saltwater-washed backbone or head fractions (n 6/group) as 25% of total protein with the remaining 75% as casein, or casein as the sole protein source (Control group, n 6) for six weeks. Blood pressure was measured on day 0 and 40. The diets containing backbone protein powder, independent of whether this fraction was washed with saltwater or not, attenuated the blood pressure increase compared to the Control group, whereas diets containing washed or unwashed head protein powder did not affect the blood pressure development. To conclude, a diet containing cod backbone protein powder attenuated the blood pressure increase in obese Zucker fa/fa rats, and this effect was not compromised by the higher sodium content in backbones washed with saltwater.
High intake of processed foods, especially those with high sodium content, is a contributor to hypertension and cardiovascular disease. This study aimed to compare the sodium content of packaged foods and beverages in Nigeria to WHO Global Sodium Benchmarks and similar products in Kenya and South Africa. The study examined packaged foods from major retail stores in the capital cities of the Federal Capital Territory, Kano, and Ogun states in Nigeria from November 2020 to March 2021. Benchmark values were based on the 2021 WHO Global Sodium Benchmarks. We used secondary data from packaged food surveys conducted in South Africa (2015, 2016 and Kenya 2019). Approximately 40.0% (n = 36) of subcategories of packaged foods were captured in the WHO global sodium benchmark. Of these, 64.0% (n = 23) exceeded the benchmarks, including ‘processed meat’ (912.0 vs. 250.0 mg/100 g), cheese (776.0 vs. 190 mg/100 g), and ‘wholegrain chips’ (930.0 vs. 470 mg/100 g). Exactly 36.0% (n = 13) had lower sodium content, such as ‘rice-based snacks’ (113.0 vs. 520 mg/100 g) and ‘dried seafood’ (400 vs. 800 mg/100 g). In seven out of eleven main food categories (64%), Nigeria had a higher sodium content compared to Kenya. Similarly, Nigeria exhibited higher sodium content than South Africa in six out of eleven food categories (55.0%). With 64.0% of Nigerian subcategories exceeding WHO benchmarks and higher sodium levels than South Africa and Kenya in most categories. These findings highlight the urgent need for targeted sodium reduction and product reformulation to align Nigeria’s packaged foods with international benchmarks.
The measurement of sodium excretion in 24-h urine samples is the recommended method to assess dietary salt intake to monitor salt-related public health policies. Ensuring complete collection of 24-h urine samples is important for the accurate assessment of salt intake. We compare the use of the objective biomarker, recovery of para-aminobenzoic acid (PABA), to self-reported 24-h urine completeness. Data collected from 868 men and women aged 19–64 years from the England Sodium Survey 2018/2019 (part of the UK National Diet and Nutrition Survey (NDNS)) were used to compare self-reported 24-h urine completeness based on a collection duration of 23–25 h, no missed urine collections/voids and a minimum urine volume of > 0·4 L against completeness based on the urinary recovery of oral doses of PABA. Two-thirds (69 %; 561/812) of participants who adhered to the PABA protocol provided a complete 24-h urine collection. Assessed by self-report, 71 % (619/868) of participants provided a complete 24-h urine collection. Sodium excretion was (geometric mean (interquartile range)) 127 (97–170) mmol/24 h with PABA and 126 (97–169) mmol/24 h by self-report; salt intake was 7·40 (5·65–9·94) g/d and 7·38 (4·53–8·83) g/d, respectively. The proportion of participants above the UK-recommended salt intake of 6 g/d was 70 % by both PABA and self-report. This study shows that the use of self-report of 24-h urine collection completeness provides an assessment of sodium excretion and dietary salt intake with the same accuracy as when PABA recovery is used to assess completeness.
Urolithiasis (UL) is a multifactorial condition whose global prevalence has been increasing in recent years, and it is closely associated with dietary factors. Diet is one of the key elements linked to the development of UL due to the intake of many nutrients that cause metabolic alterations associated with the crystallisation process and the risk of developing urinary stones. Despite the crucial role of diet, few studies have implemented dietary interventions. In this sense, dietary modifications play a fundamental role in the prevention, control and management of UL. Thus, the aim of this systematic review is to summarise the main beneficial effects of dietary interventions in populations with UL. A comprehensive search was conducted in MEDLINE/PubMed, SpringerLink, Google Scholar, Scielo and Redalyc databases for intervention studies published up to July 2025 that reported dietary interventions aimed at preventing and controlling UL. The risk of bias and quality of studies were assessed. A total of twenty-six articles were included, focusing on dietary interventions such as controlling sodium, oxalate, calcium, citrate and protein intake, as well as low-calorie diets. In addition, foods such as lemon, orange, melon, lime, cranberry, apple juices, milk, vinegar, black seed, green bean extract, probiotics and synbiotic were also explored, which promoted significant changes in serum and urinary parameters related to UL. This review compiles evidence on dietary intervention strategies that lead to significant improvements in biochemical parameters in populations with UL (PROSPERO CRD42022361702).
In the New Zealand diet, most sodium intake originates from salt added during food processing by manufacturers and in restaurant preparations(1,2). Dietary intervention may be an effective approach to reducing individuals’ sodium intake. This study investigated whether the provision of foods high in fibre or healthy fats, inadvertently effect sodium and potassium intakes. A total of 297 individuals (mean age 64 ± 10 years, n=96 females) who had a coronary event in the previous six months participated in this study. Participants were randomly allocated into one of three groups for 12 weeks: weekly delivery of foods high in healthy fats, weekly delivery of foods high in dietary fibre; and a control group that didn’t receive any groceries. All participants received basic healthy eating advice. Sodium and potassium intakes were assessed at baseline, the end of the 12-week intervention, and after a further 12 week follow up using four-day food records. Participants chose to complete these records either on paper or using the Research Food Diary application on their phone (Xyris Software Ltd., Brisbane, Australia). Food records were analysed using FoodWorks dietary analysis software (Version 10, Xyris Software Ltd., Brisbane, Australia). The mean sodium and potassium intakes recorded over the four days were used to represent participants’ intakes at each time point. Compared to the control group, sodium intake at the end of the 12-week intervention were modestly lower in both food-delivery intervention groups (-109 mg (95% CI: - 344, 125) in the healthy fats group and -175 mg (95% CI: -412, 63) in the high fibre group. Potassium intakes at 12 weeks were 284 mg higher in the high fibre group (95% CI: 4, 564), while the difference was more modest in the healthy fats group (72 mg (95% CI: -207, 350)). At the end of the 12 week follow- up, the mean sodium intake in the high fibre group was 254 mg (95% CI: -514, 7) lower than the control, whereas there was only a very small difference in the healthy fats group at -37 mg (95% CI: -300, 266). Differences in potassium intake at 24 weeks were modest for both groups (66 mg; 95% CI: -241, 374) in the healthy fats group and -53 mg (95% CI: -356, 251) in the high fibre group). The provision of healthy foods, particularly foods high in fibre, may be an effective strategy to reduce sodium and increase potassium intakes in high-risk populations.
In childhood, diets high in sodium and low in potassium contribute to raised blood pressure and cardiovascular disease later in life(1). For New Zealand (NZ) children, bread is a major source of dietary sodium, and fruit, vegetables, and milk are major dietary sources of potassium(2,3). However, it is mandatory to use iodised salt in NZ bread meaning reducing the salt and thus sodium content could put children at risk of iodine deficiency(4). Our objective was to measure the sodium, potassium, and iodine intake, and blood pressure of NZ school children 8-13 years old. A cross-sectional survey was conducted in five primary schools in Auckland and Dunedin. Primary schools were recruited between July 2022 and February 2023 using purposive sampling. Seventy-five children (n= 37 boys, 29 girls, and nine children who did not state their gender) took part. The most common ethnicity was NZ European and Other (n=54 or 72%) followed by Māori (indigenous inhabitants; n=9 or 12%) and Pasifika (n=5 or 7%). The main outcomes were 24-hour sodium and potassium intake, sodium to potassium molar ratio, 24-hour iodine intake, and BP. Sodium, potassium, and iodine intake were assessed using 24-hour urine samples and BP was assessed using standard methods. Differences by gender were tested using two-sample t-tests and nonparametric Wilcoxon two-sample tests. The mean (SD) 24-hour sodium excretion, potassium excretion, and sodium to potassium molar ratio for children with complete samples (n=59) were 2,420 (1,025) mg, 1,567 (733) mg, and 3.0 (1.6), respectively. The median (25th, 75th percentile) urinary iodine excretion was 88 (61, 122) µg per 24 hours and the mean (SD) systolic and diastolic blood pressure (n=74) were 105 (10) mmHg and 67 (9) mmHg, respectively. There was a significant difference between boys and girls for iodine (77 (43, 96) vs. 98 (72, 127) µg per 24 hours; p=0.02) but no other outcomes. In conclusion, children consumed more sodium and less potassium and iodine than World Health Organization recommendations(5). However, future research should confirm these findings in a nationally representative sample. Evidence-based, equitable interventions and policies with adequate monitoring should be considered to reduce potentially suboptimal sodium, potassium, and iodine intakes in New Zealand.
We aimed to compare the mean sodium content of New Zealand (NZ) packaged breads in 2013 and 2023 and assess compliance with the NZ Heart Foundation (HF) and World Health Organization (WHO) sodium reduction benchmarks. Sodium data were obtained from a supermarket food composition database. Mean differences between years were assessed using independent samples t-tests and chi-square tests. There was a significant reduction in the sodium content of all bread from 2013 (n=345) to 2023 (n=309) of 46 mg/100g (p<0.001). In 2013, 20% (n=70/345) of breads met the HF benchmarks, and 10% (33/345) met the WHO benchmarks; corresponding values for 2023 were 45% (n=138/309) and 18% (n=57/309) (p<0.001 for both). If continued, the modest reduction in sodium content and increase in the percentage of NZ breads meeting relevant sodium reduction benchmarks could positively affect public health, particularly if extended across the packaged food supply.
Increased out-of-home consumption may elevate sodium (Na) intake, but self-reported dietary assessments limit evidence. This study explored associations between neighbourhood exposure to fast-food and sit-down restaurants and estimated 24-hour urinary Na excretion.
Design:
A cross-sectional analysis from the ORISCAV-LUX 2 study (2016–2017). 24-hour urinary Na was estimated from a morning spot urine sample using the INTERSALT formula. Spatial access to fast-food and sit-down restaurants was derived from GIS data around participants’ addresses within 800-m and 1000-m road network buffers by summing up the inverse of the road network distance between their residential address and all restaurants within the corresponding buffer size. Multi-adjusted linear models were used to assess the association between spatial access to restaurants and estimated 24-hour urinary Na excretion.
Setting:
Luxembourg
Participants:
Urban adults age over 18 years (n 464).
Results:
Fast-food and sit-down restaurants accounted for 58·5 % of total food outlets. Mean 24-hour urinary Na excretion was 3564 mg/d for men and 2493 mg/d for women. Health-conscious eating habits moderated associations between spatial access to fast-food and sit-down restaurants and Na excretion. For participants who did not attach great importance to having a balanced diet, greater spatial access to restaurants, combining both density and accessibility, was associated with increased urinary Na excretion at 800 m (βhighvslow = 259, 95 % CI: 47, 488) and 1000 m (βhighvslow = 270, 95 % CI: 21, 520).
Conclusions:
Neighbourhood exposure to fast-food and sit-down restaurants influences Na intake, especially among individuals with less health-conscious eating habits, potentially exacerbating diet-related health disparities.
This study aimed to assess the extent to which first-morning void (FMV) urine samples can estimate sodium and potassium excretion compared with 24-hour (24-h) urine samples at the population level. We conducted a cross-sectional study collecting urine samples (FMV and 24-h) and two non-consecutive 24-h dietary recalls in a sub-sample from the Portuguese IAN-AF sampling frame. Six predictive equations were used to estimate 24-h sodium and potassium excretion from FMV urine samples. Pearson correlation coefficients were calculated to compare the association between FMV and 24-h urine collections. Cross-classifications into tertiles were computed to calculate the agreement between measured and estimated excretion with and without calibration. Pearson correlation coefficients were calculated to compare the excretion estimation from FMV and reported intake from 24-h dietary recalls. Bland–Altman plots assessed the agreement between two-day dietary recall and the best-performing calibrated equation. Data from eighty-six subjects aged 18–84 were analysed. Estimated sodium and potassium concentrations from the predictive equations moderate or strongly correlated with the measured 24-h urine samples. The Toft equation was the most predictive and reliable, displaying a moderate correlation (r=0.655) with no risk of over or underestimation of sodium excretion (p=0.096). Tanaka and Kawasaki equations showed a similar moderate correlation (r=0.54 and r=0.58, respectively) but tended to underestimate the 24-h urine excretion of potassium (p<0.001). Calibrated predictive equations using FMV urine samples provide a moderately accurate alternative and resource-efficient option for large-scale nutritional epidemiology studies when 24-h urine collection is impractical.
Edited by
Dharti Patel, Mount Sinai West and Morningside Hospitals, New York,Sang J. Kim, Hospital for Special Surgery, New York,Himani V. Bhatt, Mount Sinai West and Morningside Hospitals, New York,Alopi M. Patel, Rutgers Robert Wood Johnson Medical School, New Jersey
Renal function plays a key role in the body homeostasis as well as perioperative management of fluids. This chapter discusses the renal system anatomy and physiology as well as various metabolic disturbances of electrolytes including potassium, sodium, calcium, and magnesium.
Children and adolescents diagnosed with autism spectrum disorder (ASD) present feeding problems that may influence food acceptance and refusal. However, data regarding dietary intake variability in this population are either not available in the literature or not well-known. This cross-sectional study aimed to identify the within-person and between-person variability, and the number of days needed for a 24-hour recall (24HR) to estimate the usual intake of children and adolescents with ASD. Data were collected from 284 patients assisted at a public neuropediatric health service in the city of Pelotas, Southern Brazil. Food consumption was assessed using three non-consecutive 24HR. Within-person (S2w) and between-person (S2b) variances, the variance ratio (VR) and the distribution of energy, macronutrients and micronutrients were obtained using the Multiple Source Method® (version 1.0.1). The number of days of 24HR needed was calculated for correlation coefficients of 0·7, 0·8 and 0·9. For most nutrients, S2w was greater than S2b, resulting in VR > 1, except for age-group analyses where children up to 5 years old showed VR < 1. Two to three days of 24HR were estimated for most nutrients, considering a correlation coefficient of 0·8. Differences were observed according to sex and age group, with adolescents requiring more days of 24HR. These findings indicate the need to assess dietary variability among individuals with ASD according to the characteristics of this investigated population.
In response to increasing hypertension rates, South Africa implemented a regulation which set a maximum total Na content for certain packaged food categories. We assess changes in reported Na intake among 18–39 years old adults living in one township in the Western Cape as a result of the implementation of the regulation in 2016.
Design:
By linking one set of 24-h dietary recall data to two versions of the South Africa Food Composition Database which reflect the pre-regulation and post-regulation periods, we calculated changes in Na intake due to reformulation of food products, not behaviour change. We statistically tested differences in mean consumption in this sample with paired t tests.
Setting:
Langa, Western Cape, South Africa
Participants:
Surveyed participants were residents of Langa between 18 and 39 years old (n 2148)
Results:
Before and after the implementation of the regulation, there was a statistically significant decrease in the estimated Na intake among adults of 189·4 mg (137·5, 241·4; P = 0·00). Reported Na from cured meat (such as Russians) and certain types of soup powder, cereals and salted peanuts had a 9 to 33 per cent lower calculated Na consumption.
Conclusions:
Our conclusions show that independent of any behavioural changes on the part of consumers, it is possible to lower Na intake by using regulations to induce food manufacturers to lower the Na levels in their products. As countries explore similar regulatory strategies, this work can add to that body of evidence to inform policies to improve the food system.
Over 70% of the Earth’s surface is covered by saline environments. While the salinity of the open ocean is fairly stable, in coastal waters and estuaries, where river freshwater mixes with marine water bodies, salinity is usually highly variable, and, in some situations, such as lagoons or rock pools, evaporation of water can lead to hypersaline conditions. Changes in salinity directly affect water potential and turgor pressure in walled cells. Furthermore, salinity changes alter the intracellular concentration of inorganic ions such as sodium, which can have deleterious effects on processes such as photosynthesis and respiration. Salinity can therefore pose challenges for the physiology and growth of aquatic phototrophs. Algae respond to differences in salinity through a range of physiological mechanisms, including osmotic adjustment involving inorganic ion fluxes and the production of organically compatible solutes. In some cases, acclimation to salinity involves ultrastructural plasticity. Horizontal salinity gradients, found in environments including estuaries, lagoons or semi-isolated systems such as the Baltic Sea, promote the development of physiologically distinct variants of algal species, known as ecotypes, and eventually speciation in algae.
High dietary salt intake is a known risk factor for hypertension. However, Australians continue to consume excessive amounts of salt. The purpose of this study was to identify barriers, enablers and strategies to reduce salt in a sample of Australian adults with hypertension. This was a qualitative study. Participants were asked a set of open-ended questions during focus groups conducted between October 2020 and April 2021. Sessions were recorded and transcribed. Using an inductive approach, the transcript data from the focus groups were thematically analysed. This involved checking accuracy, becoming familiar with the data, coding responses based on questions, identifying themes through common patterns and validating themes by grouping similar questions that represented the data and study aim effectively. Thirty-one adults (55 % females) with high blood pressure participated in the focus group discussions. Participants demonstrated good knowledge of high blood pressure risk factors but lacked an understanding of recommended salt intake levels and sources of hidden salt. Challenges in reducing salt intake included the limited availability of low-salt commercial foods. Participants suggested improved food labelling and the use of technology-based interventions to promote healthier choices. Findings highlight the need for behavioural interventions, policy reforms and collaborations between the government, food industries and health organisations to address high salt intake in the population.
Sodium intake attributed to fast food is increasing globally. This research aims to develop maximum sodium reduction targets for New Zealand (NZ) fast foods and compare them with the current sodium content of products. Sodium content and serving size data were sourced from an existing database of major NZ fast-food chains. Target development followed a step-by-step process, informed by international targets and serving sizes, and previous methods for packaged supermarket foods. Sodium reduction targets were set per 100 g and serving, using a 40% reduction in the mean sodium content or the value met by 35–45% of products. Thirty-four per cent (1797/5246) of products in the database had sodium data available for target development. Sodium reduction targets were developed for 17 fast-food categories. Per 100 g targets ranged from 158 mg for ‘Other salads’ to 665 mg for ‘Mayonnaise and dressings’. Per serving targets ranged from 118 mg for ‘Sauce’ to 1270 mg for ‘Burgers with cured meat’. The largest difference between the current mean sodium content and corresponding target was for ‘Other salads’ and ‘Grilled Chicken’ (both –40% per 100g) and ‘Fries and potato products’ (–45% per serving), and the smallest, ‘Pizza with cured meat toppings’ (–3% per 100 g) and ‘Pies, tarts, sausage rolls and quiches’ (–4% per serving). The results indicate the display of nutrition information should be mandated and there is considerable room for sodium reduction in NZ fast foods. The methods described provide a model for other countries to develop country-specific, fast-food sodium reduction targets.
The objective of study was to assess 24-h urinary Na and K excretion and estimate the average salt and K intakes in a nationally representative sample of the adult population of Slovenia.
Design:
A nationally representative cross-sectional study was conducted in four stages between September and November 2022: study questionnaire, physical measurements, 24-h urine collection and laboratory analysis.
Setting:
Slovenia.
Participants:
We invited 2000 adult, non-institutionalised inhabitants of Slovenia, aged between 25 and 64 years. A stratified two-staged sample was selected from this population by the Statistical Office of Slovenia, using sampling from the Central Population Register. According to the WHO methodology, additional eligibility criteria were screened before participating. A total of 518 individuals participated in all four stages of the study, resulting in a response rate of 30 %.
Results:
The mean 24-h urinary Na excretion was 168 mmol/d (95 % CI 156, 180), which corresponds to a mean estimated intake of 10·3 g salt/d (95 % CI 9·6, 11·1). Mean 24-h urinary K excretion was 65·4 mmol/d (95 % CI 63·2, 67·5), and the estimated mean K intake was 2·93 g/d (95 % CI 2·84, 3·03). There were statistically significant differences in mean intakes between males and females. The mean sodium-to-potassium ratio was 2·7 (95 % CI 2·5, 2·8).
Conclusions:
The study results highlighted that the salt intake in the adult population of Slovenia remains much higher than recommended by the WHO, and K intakes are insufficient, as most participants did not meet the recommendations.
The effect of pH, time and temperature on the interaction of zinc with acid and base saturated dickites has been investigated. Increase in pH resulted in an increase in adsorption of zinc in the higher concentration range. The adsorption increased rapidly and then slowly with increase in the time of interaction. The variation of rate constants and the half times of reaction suggested an exchange process controlled by film and possibly particle diffusion and thereafter fixation processes. The inferences found support from the nature of adsorption isotherms. Temperature affected adsorption with exothermic interactions. The activation energy of adsorption of zinc on Na-dickite was 14.0 kcal mole−1.