Excess Dietary Sodium Research Articles

Controlled Feeding of an 8-d, High-Dairy Cheese Diet Prevents Sodium-Induced Endothelial Dysfunction in the Cutaneous Microcirculation of Healthy, Older Adults through Reductions in Superoxide

Background:While excess dietary sodium impairs vascular function by increasing oxidative stress, the dietary incorporation of dairy foods improves vascular health. We demonstrated that single-meal cheese consumption ameliorates acute, sodium-induced endothelial dysfunction. However, controlled feeding studies examining the inclusion of cheese, a dairy product that contains both bioactive constituents and sodium, are lacking. Objectives:We tested the hypothesis that microcirculatory endothelium-dependent dilation (EDD) would be impaired by a high-sodium diet, but a sodium-matched diet high in dairy cheese would preserve EDD through oxidant stress mechanisms. Methods:We gave 11 adults without salt-sensitive blood pressure (<10 mmHg Δ mean arterial pressure; 64 ± 2 y) 4 separate 8-d controlled dietary interventions in a randomized, crossover design: a low-sodium, no-dairy intervention (LNa; 1500 mg/d sodium); a low-sodium, high-cheese intervention (LNaC; 1500 mg/d sodium, 170 g/d cheese); a high-sodium, no-dairy intervention (HNa; 5500 mg/d sodium); and a high-sodium, high-cheese intervention (HNaC; 5500 mg/d sodium, 170 g/d cheese). On Day 8 of each diet, EDD was assessed through a localized infusion (intradermal microdialysis) of acetylcholine (ACh), both alone and during coinfusion of NG-nitro-L-arginine methyl ester (NO synthase inhibitor), L-ascorbate (nonspecific antioxidant), apocynin [NAD(P)H oxidase inhibitor], or tempol (superoxide scavenger). Results:Compared with LNa, microvascular responsiveness to ACh was attenuated during HNa (LNa: –4.82 ± 0.20 versus HNa: –3.21 ± 0.55 M logEC50; P = 0.03) but not LNaC (–5.44 ± 0.20 M logEC50) or HNaC (–4.46 ± 0.50 M logEC50). Further, ascorbate, apocynin, and tempol administration each increased ACh-induced vasodilation during HNa only (Ringer's: 38.9 ± 2.4; ascorbate: 48.0 ± 2.5; tempol: 45.3 ± 2.7; apocynin: 48.5 ± 2.6% maximum cutaneous vascular conductance; all Pvalues < 0.01). Conclusions:These results demonstrate that incorporating dairy cheese into a high-sodium diet preserves EDD by decreasing the concentration of superoxide radicals. Consuming sodium in cheese, rather than in nondairy sources of sodium, may be an effective strategy to reduce cardiovascular disease risk in salt-insensitive, older adults. This trial was registered at clinicaltrials.govas NCT03376555.

P4540Obesity in patients with heart failure and without diabetes mellitus is associated with longer event-free survival only among those with high dietary sodium intake

Abstract Background Obesity is paradoxically associated with better short- and long-term outcomes in patients with heart failure (HF) and without diabetes mellitus (DM). While excessive dietary sodium intake is common among obese persons, its impact on the association between obesity and outcomes has not been considered. Aim To determine whether dietary sodium intake levels would affect the association between obesity and better outcomes in patients with HF and without DM. Method A sample of 129 patients (age 60±12.4 years; 30% female) provided a single 24-hour urine collection sample to estimate dietary sodium intake. Patients were divided into 4 groups based on body mass index (BMI) and the sodium intake recommendation for HF of 3g/day (obese with high sodium intake [n=41; 32%], obese with low sodium intake [n=16; 12%], non-obese with high sodium intake [n=35; 27%], and non-obese with low sodium intake [n=37; 29%]). Patients were followed-up during an average period of 395 days to determine time to first event of all-cause hospitalization or death. Cox regression was used to determine the association between obesity and outcomes in the context of sodium intake after controlling for age, gender, NYHA class (I II vs. III IV) and LVEF. Results There were 41 patients (31.8%) who had an event of all-cause hospitalization or death. Obese patients with high sodium intake had 61% lower risk for events than those non-obese with low dietary sodium intake (figure). There were no differences in the event-free survival among other groups. Conclusion These data suggest that dietary sodium intake may be particularly important for obese patients with HF and without DM.

RE-AIM evaluation of a one-year trial of a combined educational and environmental workplace intervention to lower salt intake in Switzerland.

Reducing excessive dietary sodium may reduce cardiovascular disease risk. Environmental and behavioral interventions in workplaces may reduce salt consumption, but information on the effectiveness of workplace nutrition interventions is sparse. We used the RE-AIM framework to evaluate a one-year trial in 2015–2016 of an educational and environmental intervention to lower salt intake of employees in organizations with catering facilities in Switzerland. Five educational workshops for employees and assessments that included 24-hour urine collection were combined with five coaching sessions and food analyses in catering operations. We studied the adoption, reach, implementation, effectiveness, and maintenance of the intervention.Eight of 389 candidate organizations participated in the trial in which 145 (50% men) out of 5794 potentially eligible employees consented to participate, and 138 completed the trial with 13 in the control group.The overall mean change of daily salt intake was −0.6 g from 8.7 g to 8.1 g (6.9%). Though the mean daily salt intake of women was unaltered from 7 g, the mean intake of men declined by −1.2 g from 10.4 g to 9.2 g. Baseline salt intake, sex, and waist-to-height ratio were significant predictors of salt reduction. The analysis also highlighted pivotal determinants of low adoption and reach, and program implementation in catering operations. We conclude that a workplace program of nutrition intervention for employees and catering staff is feasible. The acceptance, effectiveness, and maintenance of nutrition interventions in the workplace require strong employer support. In a supportive food environment, interventions tailored to sex, age, and CVD risk inter alia could be successful.

Renin-angiotensin System (RAS)-mediated Antiobesity and Antihypertensive Effects of Korean Traditional Soybean Paste (Doenjang) in Rat Model of Diet-induced Obesity (P08-097-19)

ObjectivesHypertension is becoming more prevalent and one of the main cause is found in the increase of excessive dietary sodium intake. It is also risk factors for cardiovascular and kidney disease. Korean Traditional Fermented Food, doenjang, is made with high salt, so many of them are thinking that there is a lot of relation to hypertension despite reporting many health benefits. Our previous studies reported that doenjang have been associated effect of anti-obesity in human and animal study. Therefore, we expected that doenjang may have different effects on blood pressure and lipid metabolism compared to same concentrations of salt. MethodsIn this study, Sprague-Dawley rats divided into four groups, normal diet (ND), high fat diet (HD), high fat diet with 8% table salt (HDS), high fat diet with Doenjang contains 8% table salt (HDJ) for 13 weeks. The systolic blood pressure (SBP), serum chemistry, Na+ and K+ concentrations, liver and renal gene expressions were measured. ResultsDoenjang decreased systolic blood pressure (SBP), body weight and hepatic lipids. Serum chemistry, leptin and aldosterone levels were increased in HD and HDS groups while decreased in HDJ group. Results from analysing feces and urine, Na+, Ca+ and K+concentrations were changed by Doenjang. Furthermore, fatty acid synthesis-related genes expression was decreased in liver and downregulated the renin, AT1 receptor and ACE in renal cortex of doenjang treatment group. ConclusionsThese results suggest that doenjang may have anti-obesity and anti-hypertension through regulation of the renin angiotensin system. We believed that it is an important result of demonstrating that doenjang has health benefits regardless of salt content. Funding SourcesThis work was supported by the Korea Science and Engineering Foundation (KOSEF) grant funded by the Korea government (MEST) (No. 2018R1A2B6006477).

A Single High Sodium Meal Impairs Dynamic Cerebral Autoregulation

The ability for the brain to maintain cerebral blood flow despite changes in arterial blood pressure is termed cerebral autoregulation (CA). CA is known to be impaired in patients with cognitive decline and in patients that have suffered a stroke. Dysfunctional CA is also predictive of strokes and all‐cause mortality. Excess dietary sodium (Na+) consumption has been implicated in increased stroke risk. However, the effects of a high dietary Na+ consumption on cerebral autoregulation is unknown.PurposeWe tested the hypothesis that a single high‐ vs low‐Na+ meal impairs CA in healthy young adults.MethodsTwenty healthy, normotensive adults (11F/9M; age: 26±5 yrs; BMI: 24.7±3.5 kg/m2; BP: 105±6/58±4 mmHg, mean±SD) participated in this crossover design study. We provided participants with high‐ (HS: 1,495 mg) and low‐(LS: 138 mg) Na+ meals in a randomized order. Visits were separated by one week for males. We tested females in the early follicular phase of their menstrual cycle (~four weeks apart). Right middle cerebral artery (MCA) velocity (via transcranial Doppler ultrasound) and beat‐to‐beat blood pressure (via photoplethysmography) was assessed while participants lay supine for ten minutes. Dynamic CA was measured using transfer function analysis (coherence, gain, and phase) between spontaneous changes in mean arterial pressure to MCA velocity. Transfer function analysis was calculated in the 0.03–0.15 Hz range which reflects cerebral autoregulatory processes. Dynamic CA was measured prior to‐ and 60 minutes post‐meal. Biochemical data from venous blood samples were analyzed using two‐way repeated measures ANOVA (meal x time). Tukey post hoc comparisons were used when appropriate. The change in dynamic CA from baseline was analyzed using paired, two‐tailed, t‐tests.ResultsSerum Na+ was elevated on the high‐ vs low‐Na+ meal 60 minutes post‐meal (HS=141.7±0.8 vs LS=140.2±0.6 mmol/L, p&lt;0.001). Brachial mean blood pressure 60 minutes post‐meal was not different between the conditions (HS=78±5 vs LS=78±7 mmHg, p&gt;0.05). Coherence, gain and phase were not different in the very low frequency band (0.03–0.07 Hz) (p&gt;0.05 for all). The change in gain from baseline in the low frequency band (0.07–0.15 Hz) was significantly elevated following the high‐Na+ meal vs the low‐Na+ meal, implying impaired dynamic CA (HS= Δ0.14±0.46 vs LS=Δ−0.17±0.43 %/mmHg, p=0.02). The change in phase and coherence from baseline was not different between the high‐ and low‐Na+ meals (p=0.33 and p=0.17, respectively).ConclusionThese preliminary data suggest that a high sodium meal may impair dynamic cerebral autoregulation in healthy young adults.Support or Funding InformationThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Response of broiler chickens to diets containing different levels of sodium with or without microbial phytase supplementation.

Phytate induced excessive mineral excretion through poultry litter leads to poor performance and environmental pollution. Exogenous microbial phytase supplementation to poultry diets reduce the environmental excretion of nutrient and improve bird’s performance. However, excessive dietary sodium (Na) level may hinder the phytase-mediated phytate hydrolysis and negate the beneficial effects of phytase. Therefore, this experiment was conducted to investigate the effects of different concentration dietary Na on phytase activity and subsequent impact on broiler performance, bone mineralisation and nutrient utilisation. In this study, six experimental diets, consisting of three different levels of Na (1.5, 2.5, or 3.5 g/kg) and two levels of microbial phytase (0 or 500 U/kg) were formulated by using 3 × 2 factorial design. The six experimental diets were offered to 360 day-old Ross 306 male chicks for 35 days, where, each experimental diet consisted of 6 replicates groups with 10 birds. Along with growth performance, nutrient utilization, intestinal enzyme activity, dry matter (DM) content of litter and mineral status in bone were analysed. Dietary Na and phytase had no effect on bode weight gain and feed intake. Birds on the low Na diet showed higher (p < 0.05) feed conversion ratio (FCR) than the mid-Na diets. High dietary Na adversely affected (p < 0.001) excreta DM content. Phytase supplementation to the high-Na diet increased (p < 0.01) the litter ammonia content. High dietary Na with phytase supplementation improved (Na × phytase, p < 0.05) the AME value and ileal digestibility of Ca and Mg. The total tract retention of Ca, P, and Mg was reduced with high Na diet, which was counteracted by phytase supplementation (Na × phytase, p < 0.001). The diets containing mid-level of Na improved (p < 0.001) the function of Na-K-ATPase and Mg-ATPase in the jejunum. The overall results indicate that high dietary Na did not affect phytase activity but influenced the nutrient utilization of birds, which was not reflected in bird overall performance.

Sodium Levels in Packaged Foods Sold in 14 Latin American and Caribbean Countries: A Food Label Analysis.

Population-wide sodium reduction is a cost-effective approach to address the adverse health effects associated with excess sodium consumption. Latin American and Caribbean (LAC) countries consume excess dietary sodium. Packaged foods are a major contributor to sodium intake and a target for sodium reduction interventions. This study examined sodium levels in 12 categories of packaged foods sold in 14 LAC (n = 16,357). Mean sodium levels and percentiles were examined. Sodium levels were compared to regional sodium reduction targets. In this baseline analysis, 82% of foods met the regional target and 47% met the lower target. The greatest proportion of products meeting the regional target were uncooked pasta and noodles (98%), flavored cookies/crackers (97%), seasonings for sides/main dishes (96%), mayonnaise (94%), and cured/preserved meats (91%). A large proportion of foods met the lower target among uncooked pasta and noodles (88%), cooked pasta and noodles (88%), and meat/fish seasonings (88%). The highest the highest median sodium levels were among condiments (7778 mg/100 g), processed meats (870 mg/100 g), mayonnaise (755 mg/100 g), bread products (458 mg/100 g), cheese (643 mg/100 g), and snack foods (625 mg/100 g). These baseline data suggest that sodium reduction targets may need to be more stringent to enable effective lowering of sodium intake.

Educational review: role of the pediatric nephrologists in the work-up and management of kidney stones.

The incidence of nephrolithiasis in children and adolescents is increasing and appears to double every 10years. The most important role of the pediatric nephrologist is to diagnose and modify various metabolic and non-metabolic risk factors, as well as prevent long-term complications especially in the case of recurrent nephrolithiasis. The purpose of this review is to summarize the existing literature on the etiology and management of pediatric nephrolithiasis. The incidence of kidney stones is increasing; dietary and environmental factors are probably the main causes for this increased incidence. In most pediatric patients, the etiology for the kidney stones can be identified. Metabolic factors, such as hypercalciuria and hypocitraturia, urinary tract infection, and urinary stasis, constitute leading causes. Herein, we review the etiologies, diagnostic work-up, and treatment options for the most prevalent causes of kidney stones. The detrimental effects of excessive dietary sodium, reduced fluid intake, and the benefits of plant-based over animal-based protein consumption on urinary crystal formation are discussed. We also review the long-term complications. Pediatric nephrologists have an important role in the diagnostic work-up and prevention of recurring nephrolithiasis.

Bread Consumption Is Associated with Elevated Blood Pressure among Adults Living in Mexico City⁻A Sub-Analysis of the Tlalpan 2020 Study.

Excessive dietary sodium is associated with elevated blood pressure (EBP). Bread products are identified as one of the main sources of daily sodium intake. The objective of this cross-sectional study was to evaluate the association between bread and others cereal products consumption with EBP. Frequency intake of a standard serving of bread and other cereal products was recorded and categorized as: ≤3 times/month or never (reference category group) and ≥ once/week. EBP was defined as systolic blood pressure (SBP) ≥120 mmHg and/or diastolic blood pressure (DBP) ≥80 mmHg. Raw and adjusted odds ratios (OR) for the association between consumption of the studied food products and blood pressure status were estimated. Overall, 2011 participants aged 37.3 ± 9.1 years old were included. In the models adjusted for relevant covariates, consumption of one piece of bolillo or telera (OR = 1.39; 95% CI = 1.01–1.89) ≥ once/week was associated with an increased risk of EBP, compared to the reference category. Also, participants consuming one bowl of high-fiber breakfast cereal once/week were less likely to have EBP (OR = 0.73; 95% CI = 0.53–0.98). Initiatives to reduce sodium levels in bread products such as bolillo and telera are needed in Mexico to help manage the cardiovascular risk at the population level.

Evaluation of actions, barriers, and facilitators to reducing dietary sodium in health care institutions.

BackgroundGlobally, population‐wide sodium reduction strategies have been adopted and implemented to address the adverse health effects of excess dietary sodium. However, in Canada, minimal coordinated action by governments has occurred, including interventions aimed at food service operations in hospitals and long‐term care (LTC) centers. The objective of this study was to investigate actions, attitudes, barriers, and facilitators related to sodium reduction in these institutions.MethodologyA cross‐sectional survey was administered to food service administrators working in hospitals and LTC facilities in Ontario. Responses from key informants from 27 institutions, representing 9,823 patient/resident beds were included.ResultsOverall, 63.0% of institutions had an established sodium target (900–4,000 mg/day). The reported sodium level on “regular” menus was 2,845 ± 1,025 mg/day. Sixty‐three percent believed it was important to reduce sodium on inpatient/resident menus. Top facilitators reported for sodium reduction included group purchasing organizations identifying lower sodium foods (85.2%), increased availability of pre‐packaged lower sodium products (77.8%), government prioritizing and providing support and resources (74.1%), and improved taste of lower sodium foods (74.1%). Only 37.0% believed that patient/resident satisfaction would decrease with sodium reduction. Sodium reduction practices were variable among food service operations.ConclusionsThese data support the need for consistent and coordinated policies to facilitate sodium reduction in hospitals and long‐term care settings and for multi‐sectorial government, industry, and institutional support to ensure success.

Inclusion of Dairy Cheese In An 8‐day Controlled Dietary Intervention Prevents Sodium‐Induced Endothelial Dysfunction in the Cutaneous Microcirculation of Healthy Older Adults

Excess dietary sodium is associated with impaired vascular function and increased cardiovascular mortality. In controlled feeding studies, the inclusion of 3 daily servings of any dairy product improves blood pressure and measures of vascular health. Few studies have examined the inclusion of individual dairy products that contain both the beneficial bioactive dairy proteins and sodium. We recently demonstrated that single‐meal cheese consumption ameliorates acute sodium‐induced impairments in nitric oxide‐dependent vasodilation. However, controlled feeding studies examining the vasoprotective role of dairy cheese on sodium‐induced microvascular dysfunction are lacking. We hypothesized that (1) endothelium‐dependent vasodilation would be impaired by a high‐sodium diet compared to a low sodium diet, and (2) that a high‐cheese diet would preserve endothelium‐dependent vasodilation that is otherwise impaired by a high‐sodium diet. In a randomized, crossover study design, seven healthy older adults (63 ± 3 years; salt‐resistant: &lt;10 mmHg increase in mean arterial pressure, 24 hour monitoring) with normal to elevated blood pressure completed 4 separate 8‐day controlled dietary interventions: 1) low‐sodium (LNa: 1500 mg sodium) diet devoid of dairy products, 2) low‐sodium high‐cheese diet (LNaC: 1500 mg sodium, 6 oz/d cheese), 3) high‐sodium (HNa: 5500 mg sodium) diet devoid of dairy products, and 4) high‐sodium high‐cheese diet (HNaC: 5500 mg sodium, 6 oz/d cheese). At the end of each dietary intervention, subjects participated in an intradermal microdialysis protocol in which one microdialysis fiber was inserted into the forearm skin for measurement of red cell flux (laser Doppler flowmetry) during local infusion of the endothelium‐dependent agonist acetylcholine (Ach; 10−12 to 10−1 M). Data were expressed as a percentage of maximum cutaneous vascular conductance (%CVCmax; 28 mM sodium nitroprusside, 43°C). Ach‐induced vasodilation was significantly attenuated during the HNa diet compared to the LNa diet (LNa: −5.06±0.20 M vs HNa: −3.22±0.63 M logEC50: p &lt; 0.05). Conversely, Ach‐induced dilation during either the LNaC or HNaC diet was not different from the LNa diet (p &gt; 0.05). These results demonstrate that increased dietary sodium intake impairs endothelium‐dependent dilation whereas the inclusion of cheese prevents sodium‐induced endothelial dysfunction in salt‐insensitive older adults.Support or Funding InformationSupported by National Dairy CouncilThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

The Effects of Aerobic Fitness on Blood Pressure Reactivity During Controlled Low and High Sodium Diets

PurposeIncreased blood pressure (BP) reactivity to acute exercise is predictive of future cardiovascular events. Excess dietary sodium exaggerates centrally‐mediated BP reactivity in salt‐resistant rodents. Regular exercise attenuates BP reactivity in rodents, presumably through increased fitness. However, the influence of dietary sodium on BP reactivity has not been investigated in humans. Furthermore, the interaction between dietary sodium and aerobic fitness on neurovascular regulation has not been investigated in humans. Therefore, we sought to test the hypotheses that 1) high dietary sodium exaggerates BP reactivity to acute hand‐grip exercise in humans; and 2) high aerobic fitness modulates high dietary sodium‐induced alterations in BP reactivity in healthy, young adults.MethodsThirteen healthy, young adults (8F/5M, age: 28±2 yrs, BMI: 24.1±0.9 kg/m2; BP: 109±2/63±2mmHg; Mean±SEM) completed randomized, controlled 10‐day diets of high (7 g/day) and low (1 g/day) dietary sodium separated by ≥ four weeks. Beat‐to‐beat laboratory BP was measured via photoplethysmography on day 10 of both diets. BP reactivity was assessed as ΔBP (mmHg) during the final minute of a two‐minute static hand‐grip exercise trial at 40% maximal voluntary contraction compared to a preceding 10‐minute baseline. Aerobic fitness was assessed as VO2Peak using a progressive‐intensity treadmill exercise protocol and indirect calorimetry. Differences in high‐ vs. low‐sodium BP reactivity (high – low sodium ΔBP reactivity; using the final minute of hand‐grip exercise BP data) was compared by splitting the participants into two categories of fitness (low vs. high) and completing an independent‐samples t‐test. Low aerobic fitness was defined as a relative VO2Peak of ≤40 ml*kg−1*min−1. Using this criterion, seven participants were classified as having “low aerobic fitness” and six were classified as having “high aerobic fitness”. Twenty four‐hour urinary sodium excretion was measured to ensure dietary compliance.ResultsUrinary Na+ excretion increased on the high‐ vs. low‐sodium diet (259.7±18.4 vs. 33.2±6.6 mmol/24 hours; p &lt; 0.01). There was no difference in 24‐hr mean arterial BP on the high‐ vs. low‐sodium diet (82.9±2.1 vs. 79.8±2.4 mmHg, p &gt; 0.05). The high sodium diet augmented systolic (24.2±2.6 vs. 17.4±3.1; p = 0.03), but not diastolic (18.7±1.8 vs. 15.5±2.5; p = 0.19) BP reactivity during acute hand‐grip exercise in all participants. There was a trend (p = 0.06) for the low aerobic fitness participants to demonstrate greater Δ systolic BP reactivity compared to the high aerobic fitness participants (11.5±4.3 vs. 1.1±2.4 ΔBP reactivity). However, there was not a statistically significant difference (p = 0.32) between the low and high aerobic fitness participants regarding Δ diastolic BP reactivity between diets (5.5±3.5 vs. 0.7±2.9 ΔBP reactivity).ConclusionThese preliminary data suggest that 1) high dietary sodium exaggerates systolic BP reactivity to acute hand‐grip exercise in humans; and 2) high aerobic fitness may modulate some of the neurovascular effects of high dietary sodium in healthy young adults, although more data is needed.Support or Funding InformationNIH Grant 1RO1HL128388This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Abstract P252: The Effects of Sodium Reduction on Metabolism and Thirst

Background: Recent studies challenge the traditional understanding of sodium physiology. Some animal studies suggest that high sodium intake may induce catabolism, leading to weight loss. Other studies suggest that high sodium intake might reduce, rather than increase, thirst. Hypothesis: Higher sodium intake increases thirst, fluid intake, and sodium excretion without altering energy intake or lowering weight. Methods: In the DASH-Sodium feeding study, adults with pre- or stage 1 hypertension without antihypertensive medications, were randomly assigned to the DASH diet or a control diet. On their assigned diet, participants consumed each of three sodium levels for 4 weeks (randomized crossover design). Participants were provided all meals, but could drink water freely. Throughout the trial, calorie intake was adjusted to keep weight constant. The three sodium levels (at 2100 kcal/d) were: low (1150 mg), medium (2300 mg), and high (3450 mg). Weight, energy intake, self-reported thirst, urine volume, plasma renin, serum aldosterone, urine osmolality, and urine sodium excretion were assessed at the end of each period. Results: Among 412 participants (57% women, 57% black, mean age 48 yrs), weight increased slightly with higher sodium on the control diet, but not the DASH diet; energy intake did not vary across sodium levels in both diets ( P -trends &gt; 0.34) ( Table ). In contrast, participants reported more thirst with high vs low sodium (both diets P -trends &lt; 0.001) and potentially higher fluid intake (urine volume) during the control diet (1,566 vs 1,491 ml on high vs low sodium; P -trend = 0.07). On both diets, plasma renin and serum aldosterone were lower with higher sodium (each P -trend &lt; 0.001). Likewise, both urine osmolality and sodium excretion were higher with higher sodium intake (all P -trends &lt; 0.001). Conclusions: Higher sodium intake did not alter energy intake, but did increase thirst and sodium excretion. These findings are consistent with the traditional understanding of the physiology of excess dietary sodium intake.

Adoptable Interventions, Human Health, and Food Safety Considerations for Reducing Sodium Content of Processed Food Products.

Although vital for maintaining health when consumed in moderation, various epidemiological studies in recent years have shown a strong association between excess dietary sodium with an array of health complications. These associations are robust and clinically significant for development of hypertension and prehypertension, two of the leading causes of preventable mortality worldwide, in adults with a high-sodium diet. Data from developed nations and transition economies show worldwide sodium intake of higher than recommended amounts in various nations. While natural foods typically contain a moderate amount of sodium, manufactured food products are the main contributor to dietary sodium intake, up to 75% of sodium in diet of American adults, as an example. Lower cost in formulation, positive effects on organoleptic properties of food products, effects on food quality during shelf-life, and microbiological food safety, make sodium chloride a notable candidate and an indispensable part of formulation of various products. Although low-sodium formulation of each product possesses a unique set of challenges, review of literature shows an abundance of successful experiences for products of many categories. The current study discusses adoptable interventions for product development and reformulation of products to achieve a modest amount of final sodium content while maintaining taste, quality, shelf-stability, and microbiological food safety.

The Economic Impact of Dietary Sodium Reduction In Canada

The average Canadian sodium intake is double the amount recommended. Excess dietary sodium consumption is a risk factor for the development of high blood pressure (BP), estimated to cause about 30% of hypertension and 17% of cardiovascular disease (CVD). The cost attributable to high dietary sodium intake in Canada is unknown. Mathematical modeling can be used to explore the potential health and economic impacts of a population-wide reduction in dietary sodium. The Canadian Cardiovascular Disease Policy model (C-CVDPM) is a computer simulation state transition model, which simulates CVD events, costs and health consequences from a public payer perspective for the Canadian population. It can be used to evaluate the economic impact of population health interventions. Using the CVDPM and a 50-year time horizon, we examined the health and economic impact of a population-wide reduction in dietary sodium of 1800 mg/day. Sensitivity analyses were conducted using modest dietary sodium reductions of 500 mg/day and 1500 mg/day. Reducing dietary sodium by 1800 mg/day is projected to reduce the annual number of new cases of coronary heart disease by 199,808, stroke by 120,381, and myocardial infarction by 115,528, and to reduce the annual number of deaths from any cause, including CVD by 89,734. Overall, the model projected a gain of 24,285 quality-adjusted life years (QALYs), and a savings of $414 million, annually. Modest reductions in dietary sodium intake were also cost saving. A population-wide reduction in dietary sodium could substantially decrease healthcare costs and improve health outcomes. The results of this work may be useful to policy makers in revising Canadian sodium regulation and policy.

Food Sources of Sodium Intake in an Adult Mexican Population: A Sub-Analysis of the SALMEX Study.

Excessive dietary sodium intake increases blood pressure and cardiovascular risk. In Western diets, the majority of dietary sodium comes from packaged and prepared foods (≈75%); however, in Mexico there is no available data on the main food sources of dietary sodium. The main objective of this study was to identify and characterize the major food sources of dietary sodium in a sample of the Mexican Salt and Mexico (SALMEX) cohort. Adult male and female participants of the SALMEX study who provided a complete and valid three-day food record during the baseline visit were included. Overall, 950 participants (mean age 38.6 ± 10.7 years) were analyzed to determine the total sodium contributed by the main food sources of sodium identified. Mean daily sodium intake estimated by three-day food records and 24-h urinary sodium excretion was 2647.2 ± 976.9 mg/day and 3497.2 ± 1393.0, in the overall population, respectively. Processed meat was the main contributor to daily sodium intake, representing 8% of total sodium intake per capita as measured by three-day food records. When savory bread (8%) and sweet bakery goods (8%) were considered together as bread products, these were the major contributor to daily sodium intake, accounting for the 16% of total sodium intake, followed by processed meat (8%), natural cheeses (5%), and tacos (5%). These results highlight the need for public health policies focused on reducing the sodium content of processed food in Mexico.

Cardiovascular risk associated with high sodium-containing drugs: A systematic review.

BackgroundExcess dietary sodium is associated with increased blood pressure (BP). Some drugs are associated with high sodium intake (in particular effervescent tablets), but the cardiovascular risk associated with such high sodium-containing drugs (HSCD) is largely underevaluated.ObjectivesTo summarize the evidence for a potential cardiovascular risk associated with exposure to HSCD, and to highlight possible risk factors associated with this iatrogenic issue; in general and/or specific populations.MethodsWe conducted a systematic review, by searching electronic databases including MEDLINE, EMBASE, Web of Science, CENTRAL and grey literature between 1960 and 2015. We included studies that reported modification of cardiovascular parameters or incidence/prevalence of cardiovascular outcomes, between a group of subjects exposed to HSCD relative to a non-exposed group. The threshold used to identify HSCD was 391 mg/day. We did not consider studies evaluating exposure to sodium as an active ingredient or those focusing on dialysis solutions or enteral/parenteral nutrition. Study quality was assessed using the EPHPP tool.ResultsA total of eight studies met our inclusion criteria. Four reported results for short-term exposure to HSCD (≤ 7 days) on BP fluctuations. One study reported an elevation of BP (associated sodium intake: 1,656 mg/day). Four studies evaluated a long-term exposure (≥ 2 years or discontinuation of a chronic treatment). Two studies reported iatrogenic risk. For these studies, drug associated sodium intake was high (> 1,500 mg/day) in patients with comorbidities (in particular, diabetes mellitus and hypertension).ConclusionDespite numerous study limitations, this systematic review suggests three potential synergistic risk factors for cardiovascular complications after exposure to HSCD: a high sodium intake (≥ 1,500 mg/day), a long duration of exposure, and the presence of comorbidities. Further studies are required to characterize this iatrogenic risk.Trial registrationPROSPERO CRD42016047086.

The impact of voluntary targets on the sodium content of processed foods in Brazil, 2011-2013.

Brazilians consume excessive dietary sodium (4700mg/d); hence, the reduction of dietary sodium intake has been a Brazilian government priority. A set of strategies has been implemented that includes food and nutrition education initiatives and the reduction in the sodium content of processed foods and foods consumed out of the households. Since 2011, the Ministry of Health has selected priority food categories that contribute to over 90% of sodium intake from processed foods and have set biannual voluntary targets for sodium reduction with food industries to encourage food reformulation. Three rounds of monitoring of the sodium content on food labels have been conducted for instant pasta, commercially produced breads, cakes and cake mixes, cookies and crackers, snacks, chips, mayonnaise, salt-based condiments, and margarine. Between 90% and 100% of the food products achieved the first targets in the 2011-2013 period, and the average sodium content of food categories was reduced from 5% to 21% in these first 2years. These data show that with close monitoring and government oversight, voluntary targets to reduce the sodium content in processed foods can have a significant impact even in a short time frame. The Brazilian strategy will be continuously monitored to maximize its impact, and, if necessary in the future, a transition to regulatory approaches with stronger enforcement may be considered.

Hypertension's 3 Dilemmas and 3 Solutions: Pharmacology of the Kidney in Hypertension.

The Hypertension Community has 3 conflicting dilemmas: a goal systolic pressure of 120 mm Hg or less (the SPRINT Trials), 40% of our 60,000,000 hypertensives still sustain blood pressures above 140/90 mm Hg, and our most potent antihypertensive drug minoxidil sits on the sidelines, imprisoned in the Food and Drug Administration's Black Box designation. My solutions to these dilemmas are: (1) review of the facts of our most potent antihypertensive drug minoxidil which is essentially free of toxicity, (2) treatment focus on the fundamental cause of high blood pressure (HBP) and excess dietary sodium and, (3) prevention of, and/or reversal of, the fundamental mechanism of worsening hypertension, arteriolar hypertrophy. My focus at UT Southwestern in Dallas was on extremely severely hypertensive patients with a quantifiable, measurable complication of HBP, progression of nephrosclerotic damage to kidneys. This model had the greatest likelihood of exposing fundamental disregulatory mechanisms in hypertensive patients (which it did) and the potential for study of the most relevant antihypertensive drug interactions to achieve optimal blood pressure control (which it did). By maintaining diastolic pressures at 80 mm Hg or less in the first National Institutes of Health-supported, long-term randomized clinical trial to save the kidneys, the bases for a fundamental blood pressure support mechanism (arteriolar hypertrophy) was illuminated but not fully described until now. This fundamental hypertensinogenic mechanism results from HBP but with time and severity, becomes its own raison d'être. I am now aged 84 years. As a result of a stroke 20 years ago, which caused permanent double vision, and because of poor blood pressure control with triple therapy, I started using minoxidil 5 mg/d along with atenolol and occasional furosemide. Now, along with some dietary salt restriction, my resting blood pressure is 110/65-125/75 and, despite >30 years history of HBP, I have no retinal arteriolar hypertrophy nor arcus senilis (Dr. Schwartz-U. of Miami) which is almost universally present at this age. Yes, prevention of, or reversal of, arteriolar hypertrophy should be a central focus of HBP treatment. I simply wish to share a bit of accumulated wisdom that might be of use to others.

High dietary sodium intake is associated with low bone mass in postmenopausal women: Korea National Health and Nutrition Examination Survey, 2008-2011.

Several studies have reported that large amount of dietary sodium intake is highly associated with elevated urinary calcium. However, the direct effect of excessive dietary sodium intake on bone mass, as a risk factor for osteoporosis, is still a controversial issue. The aim of the present study was to assess the relationship between high intake of sodium and lower bone mass and risk of osteoporosis in adult women. This cross-sectional study was performed using data from the Korea National Health and Nutrition Examination Survey (KNHANES), 2008-2011. Participants (n=9526 women older than 18years) were divided into a premenopausal (n=4793) and postmenopausal (n=4733) group. Both groups were subdivided into five groups according to quintiles of energy-adjusted sodium intake. Multiple regression analysis was performed to assess relationships between sodium intake and lower bone mass. Multivariate linear regression analysis showed that high sodium intake was negatively associated with bone mineral content (BMC) and bone mineral density (BMD) in postmenopausal women. After adjusting confounding factors, high sodium intake was negatively associated with BMC and BMD of the lumbar spine in postmenopausal women. Postmenopausal women, whose sodium intake was ≥2000mg/day (odds ratio 1.284, 95% CI 1.029-1.603, P=0.027), were at risk of developing osteoporosis after adjustment of confounding variables. The present study suggested that high sodium intake could be a potential risk factor for low bone mass after adjusting for confounding factors in postmenopausal women.