Measuring Sodium from Discretionary Salt: Comparison of Methods.

(1) Background: The best method to assess discretionary salt intake in population surveys has not been established. (2) Methods: This secondary analysis compared three different methods of measuring sodium intake from discretionary salt in a convenience sample of 109 adults in New Zealand. Participants replaced their household salt with lithium-tagged salt provided by researchers over eight days. Baseline 24 h urine was collected, and two further 24 h urine and 24 h dietary recalls were collected between days six and eight. Discretionary salt was estimated from the lithium-tagged salt, focused questions in the 24 h dietary recall, and the 'subtraction method' (a combination of 24 h urine and 24 h dietary recall measures). (3) Results: Around one-third of estimates from the 'subtraction method' were negative and therefore unrealistic. The mean difference between 24 h dietary recall and lithium-tagged salt estimates for sodium from discretionary salt mean were 457 mg sodium/day and 65 mg/day for mean and median, respectively. (4) Conclusions: It is possible to obtain a reasonable estimate of discretionary salt intake from careful questioning regarding salt used in cooking, in recipes, and at the table during a 24 h recall process to inform population salt reduction strategies.

Adjusting the Iodine Content of Iodized Salt to Meet the Recommended Intake for Females of Reproductive Age: A Simulation Study with a Reduced Sodium Scenario.

BACKGROUND: The use of iodized salt is a key strategy to increase iodine intake worldwide. In many countries, including New Zealand, females of reproductive age are still at risk of being mildly iodine deficient. OBJECTIVE: This study aimed to determine the level of iodization of salt needed to ensure that females aged 18 to 40 y have an adequate intake of iodine in 2 scenarios: current discretionary salt intake and reduced discretionary salt intake. METHOD: Data from nonpregnant, nonlactating females aged 18 to 40 y (n = 795) who took part in the 2008/09 New Zealand Adult Nutrition Survey and completed a 24-h dietary recall were used. Iodine intake was determined from all foods except bread and discretionary salt, which are fortified with iodine. Iodine from bread and salt was estimated at different levels of salt iodization, starting at 25 mg iodine/kg salt and increasing incrementally by 5 mg/kg, and added to calculate total iodine intake. The simulation concluded when the appropriate iodine content in salt was found using the estimated average requirement (EAR) cut-point method. RESULTS: In the 2 scenarios, current discretionary salt intake (i.e., 400 mg/d) and reduced discretionary salt intake (i.e., 304 mg/d), the iodine concentration of salt is required to be 55 mg/kg and 70 mg/kg for no more than 2% of females to have an iodine intake below the EAR of 100 µg of iodine/d, respectively. In both scenarios and at all levels of iodine concentration, no one was above the upper level of intake of iodine of 1100 µg/d. CONCLUSIONS: This study found that females of reproductive age need to consume iodized salt at the higher end of the legislated range of 25 to 65 mg/kg. If strategies to reduce sodium intake were adopted, the range would need to increase, or iodized salt would need to be included in a wider range of staple foods.

The World Hypertension League Science of Salt: a regularly updated systematic review of salt and health outcomes studies (Sept 2019 to Dec 2020).

The World Hypertension League Science of Salt health outcomes review series highlights high-quality publications relating to salt intake and health outcomes. This review uses a standardised method, outlined in previous reviews and based on methods developed by WHO, to identify and critically appraise published articles on dietary salt intake and health outcomes. We identified 41 articles published between September 2019 to December 2020. Amongst these, two studies met the pre-specified methodological quality criteria for critical appraisal. They were prospective cohort studies and examined physical performance and composite renal outcomes as health outcomes. Both found an association between increased/higher sodium intake and poorer health outcomes. Few studies meet criteria for high-quality methods. This review adds further evidence that dietary salt reduction has health benefits and strengthens evidence relating to health outcomes other than blood pressure and cardiovascular disease. We observe that most studies on dietary sodium do not have adequate methodology to reliably assess sodium intake and its association with health outcomes.

Sodium in the New Zealand diet: proposed voluntary food reformulation targets will not meet the WHO goal of a 30% reduction in total sodium intake.

PURPOSE: To simulate the potential impact of the HeartSAFE 2020 programme, a food reformulation initiative by the New Zealand (NZ) Heart Foundation, on sodium intake in the NZ adult population. METHODS: A representative sample of NZ adults aged 15 years and older completed a 24-h diet recall survey, with 25% of participants completing a second diet recall, in the 2008/09 New Zealand Adult Nutrition Survey (n = 4721). These data were used to estimate sodium intakes of participants. The effect of altering the sodium content of 840 foods in 17 categories and 35 sub-categories included in the NZ HeartSAFE 2020 programme was simulated. The simulated sodium intake reductions in each food sub-category for the entire sample were calculated. Using sampling weights, simulated reductions in population sodium intake and by sociodemographic subgroups were also analysed. RESULTS: Sodium intake from foods included in the HeartSAFE 2020 programme was 1307 mg/day (95% CI 1279, 1336) at baseline. After applying the HeartSAFE 2020 targets, potential sodium intake was 1048 mg/day (95% CI 1024, 1027). The absolute sodium reduction was 260 mg/day (95% CI 252, 268), corresponding to 20% sodium reduction for the foods included in the NZ HeartSAFE programme. CONCLUSION: Current sodium targets featured in the NZ HeartSAFE programme will not meet the 30% sodium intake reduction set out by the WHO Global Action Plan. A more comprehensive strategy consistent with the WHO SHAKE Technical Package is needed to advance the goal of sodium intake reduction.

The quantification of sodium intake from discretionary salt intake in New Zealand using the lithium-tagged salt method.

Introduction: Discretionary salt (added in cooking at home or at the table) is a source of sodium and iodine in New Zealand. The amount of discretionary salt consumed in a population has implications on policies regarding sodium and iodine. Sodium intake from discretionary salt intake has not been quantified in New Zealand. The aim of this study was to estimate the proportion of total sodium that comes from discretionary salt in adults using the lithium-tagged salt method. Methods: A total of 116 healthy adults, who were not pregnant or breastfeeding, regularly consume home-cooked meals and use salt during cooking or at the table, aged 18-40 years from Dunedin, New Zealand were recruited into the study. The study took place over a 9-day period. On Day 1, participants were asked to collect a baseline 24-h urine to establish their normal lithium output. From Day 2 to Day 8, normal discretionary salt was replaced with lithium-tagged salt. Between Day 6 and Day 8, participants collected another two 24-h urine samples. A 24-h dietary recall was conducted to coincide with each of the final two 24-h urine collections. Urinary sodium was analysed by Ion-Selective Electrode and urinary lithium and urinary iodine were analysed using Inductively Coupled Plasma Mass Spectrometry. The 24-h dietary recall data was entered into Xyris FoodWorks 10. All statistical analysis were conducted using Stata 17.0. Results: A total of 109 participants with complete 24-h urine samples were included in the analysis. From the 24-h urine collections, the median urinary excretion of sodium and iodine was 3,222 mg/24 h (25th, 75th percentile: 2516, 3969) and 112 µg/24 h (82, 134). The median estimated sodium intake from discretionary salt was 13% (25th, 75th percentile: 7, 22) of the total sodium intake or 366 mg/24 h (25th, 75th percentile: 186, 705). Conclusion: The total sodium intake was higher than the suggested dietary target of 2,000 mg/day. In this sample of healthy adults 18 to 40 years old, 13% of total sodium intake derived from discretionary salt. Discretionary salt is an additional source of iodine if iodised salt is used. Policies to reduce sodium intake is recommended to include a range of strategies to target discretionary and non-discretionary sources of salt and will need to take into account the contribution of iodine from discretionary salt intake.

Potassium.

Potassium is an essential nutrient that performs a vital role in cellular functions including maintaining fluid balance and osmolality of cells. Potassium balance is maintained by the kidney and the majority of ingested potassium is excreted in the urine. There is strong evidence of a negative association between dietary potassium and blood pressure, and some evidence (much of it indirect) of negative associations between dietary potassium and cardiovascular disease (particularly stroke and coronary heart disease) and kidney disease (chronic renal failure, and kidney stones). Blood pressure lowering is particularly associated with high potassium and low sodium diets. Important dietary sources of potassium include fruit and vegetables (including rice, potatoes, legumes and wholegrains), dairy products, and animal proteins. Worldwide, diets are low in potassium compared to dietary guidelines. Interventions focused on increasing dietary potassium will have major benefits including improvements in diet, reducing non-communicable disease and enhancing planetary health.

Folate and Vitamin B-12 Status Is Associated With Bone Mineral Density and Hip Strength of Postmenopausal Chinese-Singaporean Women.

The role of micronutrients such as folate and vitamin B-12 in bone quality has been widely studied with conflicting results. Ethnicity seems to play a large role on nutrient intake, as diet varies across cultures. In this study, we examined the relationships of BMD, proximal femur strength, and bone resorption with plasma folate and vitamin B-12 in a cohort of 93 healthy postmenopausal women of Chinese-Singaporean descent. The parameters examined were areal (aBMD) and volumetric BMD (vBMD) of the proximal femur and the third lumbar vertebra (L3), total body aBMD, proximal femur bending, compressive and impact strength indices (composite strength indices) and circulating levels of C-telopeptide of type I collagen. Eighteen participants (19.4%) had aBMD in the osteoporotic range (osteoporosis group), 59 (63.4%) in the osteopenic range (osteopenia group), and the remaining 16 (17.2%) in the normal range (normal BMD group). Circulating folate levels were significantly higher in the normal BMD group compared with the osteoporosis group. Using linear regression analysis, we found that overall, aBMD and vBMD are positively associated with folate concentrations, whereas composite strength indices were positively associated with vitamin B-12 concentrations. These findings support the existing literature and suggest a link between levels of circulating folate/vitamin B-12 and BMD/bone strength in the cohort examined. Further investigation is needed to examine if individuals with inadequate circulating levels of these nutrients could decrease their risk for fragility fractures through better nutrition or vitamin supplementation. © 2020 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

A fructose-based meal challenge to assess metabotypes and their metabolic risk profile: A randomized, crossover, controlled trial.

OBJECTIVES: The first aim of this study was to determine the metabolic type of individuals based on the postprandial metabolic response after the ingestion of a meal challenge that was high protein and either high glucose (high GI) or fructose (low GI). The second aim was to compare the baseline characteristics between the different metabolic types (metabotypes). The third aim was to assess whether the inclusion of fructose or glucose in a high-protein breakfast modulated the glucose, insulin, and TG response over a 4-h period. METHODS: The study included 46 Asian women with a body mass index between 17 and 28 kg/m2 in a randomized crossover design. Metabolic typing was based on the assessment of the postprandial glycemic, insulin and triacylglycerol (TG) response after the ingestion of two high-protein meal challenges either high in fructose or glucose. Baseline characteristics were compared between the different metabolic types. Baseline and 4-h postprandial blood samples were collected and glucose, insulin, and TG levels were analyzed. Cluster analysis was used to phenotype the participants in distinct groups. Baseline characteristics including anthropometry, glycemic, and lipid profiles and resting metabolic rate were compared among the metabolic types. RESULTS: Cluster analysis revealed that women could be grouped into three metabolic types based on postprandial glucose, insulin, and TG response after the fructose meal challenge: cluster 1 with an average glucose + high TG response (highTG; n = 12), cluster 2 with a high glucose + average TG response (highGLU; n = 8), and cluster 3 with an average glucose + average TG response (Avg; n = 26). Post hoc analysis revealed significantly greater waist-to-hip ratio and a worse lipid profile for the highTG cluster and a higher fasting blood glucose, body mass index, fat percentage, and hip circumference in the highGLU cluster. CONCLUSIONS: Three metabolic types with a distinct metabolic response could be distinguished after a high fructose meal. The results suggest a different risk profile and may indicate why some people develop diabetes in an obesogenic environment. Improved metabolic-type assessments will enable us to develop and optimize nutritional and medical interventions for individuals with differing diabetes risk.