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Purpose of Review: The scientific consensus on which global health organizations base public health policies is that high sodium intake increases blood pressure (BP) in a linear fashion contributing to cardiovascular disease (CVD). A moderate reduction in sodium intake to 2000 mg per day helps ensure that BP remains at a healthy level to reduce the burden of CVD., Recent Findings: Yet, since as long ago as 1988, and more recently in eight articles published in the European Heart Journal in 2020 and 2021, some researchers have propagated a myth that reducing sodium does not consistently reduce CVD but rather that lower sodium might increase the risk of CVD. These claims are not well-founded and support some food and beverage industry's vested interests in the use of excessive amounts of salt to preserve food, enhance taste, and increase thirst. Nevertheless, some researchers, often with funding from the food industry, continue to publish such claims without addressing the numerous objections. This article analyzes the eight articles as a case study, summarizes misleading claims, their objections, and it offers possible reasons for such claims. Our study calls upon journal editors to ensure that unfounded claims about sodium intake be rigorously challenged by independent reviewers before publication; to avoid editorial writers who have been co-authors with the subject paper's authors; to require statements of conflict of interest; and to ensure that their pages are used only by those who seek to advance knowledge by engaging in the scientific method and its collegial pursuit. The public interest in the prevention and treatment of disease requires no less., (© 2021. The Author(s).)

In China, a major source of sodium is salt added during cooking. In this context, use of a salt-restriction spoon (SRS) has been promoted in public health campaigns and by health care providers. To describe use of and factors associated with SRS use, knowledge of correct use, and actual correct use. This study is a population-based, representative survey of 7512 residents, aged 18 to 69 years, of China's Zhejiang Province. The survey, which was conducted in 2017 using a multistage random sampling strategy, collected demographic information, SRS use, and physical measurements; a 24-h urine collection was obtained from 1,496 of the participants. The mean age of the participants was 44.8 years, 50.1% were females, and over 1/3 (35.3%) were classified as hypertensive. Mean 24-h urinary sodium and potassium excretions were 167.3(72.2) mmol/24 h and 38.2(18.2) mmol/24 h, respectively. Only 12.0% (899/7512) of participants once used or were currently using SRS; of the 899 users, 73.4% knew how to use the SRS correctly, and just 46.5% actually used it correctly. SRS use was more commonly associated with behavioral factors rather than socio-demographic factors. Initiation of SRS use by health care providers was associated with correct technical knowledge of SRS. Lower sodium-to-potassium ratio was associated with SRS use, while SRS use was not associated with urinary sodium and potassium excretion. Use of SRS was uncommon in Zhejiang Province of China. Given that a common source of sodium in China is salt added during cooking, use of SRS is an appealing strategy, ideally as part of a multi-component campaign.

Lightheadedness after standing contributes to adverse clinical events, including falls. Recommendations for higher sodium intake to treat postural lightheadedness have not been evaluated in a trial setting. The Dietary Approaches to Stop Hypertension (DASH)-Sodium trial (1998-1999) tested the effects of the DASH diet and sodium reduction on blood pressure (BP). Participants were randomly assigned to DASH or a typical Western diet (control). During either diet, participants ate three sodium levels (50, 100, 150 meq/d at 2100 kcal) in random order for 30-days, separated by 5-day breaks. Participants reported the presence and severity of postural lightheadedness at baseline and after each feeding period. There were 412 participants (mean age 48 years; 57% women; 57% black). Mean baseline SBP/DBP was 135/86 mm Hg; 9.5% reported baseline lightheadedness. Among those consuming the DASH diet, high vs low sodium increased lightheadedness (OR 1.71; 95% CI: 1.01, 2.90; P = 0.047) and severity of lightheadedness (P = 0.02), but did not affect lightheadedness in those consuming the control diet (OR 0.77; 95% CI: 0.46, 1.29; P = 0.32). Among those consuming high vs low sodium in the context of the DASH diet, adults <60 vs ≥60 years old experienced more lightheadedness (P-interaction = 0.04), along with obese vs non-obese adults (P-interaction = 0.01). In the context of the DASH diet, higher sodium intake was associated with more frequent and severe lightheadedness. These findings challenge traditional recommendations to increase sodium intake to prevent lightheadedness., (©2019 Wiley Periodicals, Inc.)

Importance: In 2010, the Institute of Medicine (now the National Academy of Medicine) recommended collecting 24-hour urine to estimate US sodium intake because previous studies indicated 90% of sodium consumed was excreted in urine., Objective: To estimate mean population sodium intake and describe urinary potassium excretion among US adults., Design, Setting, and Participants: In a nationally representative cross-sectional survey of the US noninstitutionalized population, 827 of 1103 (75%) randomly selected, nonpregnant participants aged 20 to 69 years in the examination component of the National Health and Nutrition Examination Survey (NHANES) collected at least one 24-hour urine specimen in 2014. The overall survey response rate for the 24-hour urine collection was approximately 50% (75% [24-hour urine component response rate] × 66% [examination component response rate])., Exposures: 24-hour collection of urine., Main Outcomes and Measures: Mean 24-hour urinary sodium and potassium excretion. Weighted national estimates of demographic and health characteristics and mean electrolyte excretion accounting for the complex survey design, selection probabilities, and nonresponse., Results: The study sample (n = 827) represented a population of whom 48.8% were men; 63.7% were non-Hispanic white, 15.8% Hispanic, 11.9% non-Hispanic black, and 5.6% non-Hispanic Asian; 43.5% had hypertension (according to 2017 hypertension guidelines); and 10.0% reported a diagnosis of diabetes. Overall mean 24-hour urinary sodium excretion was 3608 mg (95% CI, 3414-3803). The overall median was 3320 mg (interquartile range, 2308-4524). In secondary analyses by sex, mean sodium excretion was 4205 mg (95% CI, 3959-4452) in men (n = 421) and 3039 mg (95% CI, 2844-3234) in women (n = 406). By age group, mean sodium excretion was 3699 mg (95% CI, 3449-3949) in adults aged 20 to 44 years (n = 432) and 3507 mg (95% CI, 3266-3748) in adults aged 45 to 69 years (n = 395). Overall mean 24-hour urinary potassium excretion was 2155 mg (95% CI, 2030-2280); by sex, 2399 mg (95% CI, 2253-2545) in men and 1922 mg (95% CI, 1757-2086) in women; and by age, 1986 mg (95% CI, 1878-2094) in adults aged 20 to 44 years and 2343 mg (95% CI, 2151-2534) in adults aged 45 to 69 years., Conclusions and Relevance: In cross-sectional data from a 2014 sample of US adults, estimated mean sodium intake was 3608 mg per day. The findings provide a benchmark for future studies.

Estimation of dietary sodium intake is problematic. The most accurate measure is average sodium excretion from multiple 24-hour urine collections, but such an approach is impractical. Using data from the Women's Health Initiative, Prentice et al. (Am J Epidemiol. 2017;186(9):1035-1043) assessed the relationship of calibrated estimates of sodium and potassium excretion with cardiovascular outcomes. The calibrated estimates were a function of self-reported sodium-to-potassium ratio from a food frequency questionnaire, age, body mass index, race, supplement use, smoking status, educational level, income, and aspirin use. In general, associations with outcomes using the calibrated estimates were in the expected direction: direct for the sodium-to-potassium ratio and sodium intake and indirect for potassium. The unexpected associations were an increased risk of hemorrhagic stroke with lower sodium-to-potassium ratio and sodium intake and increased risk with higher potassium intake, along with a null relationship of sodium intake with ischemic stroke. Overall, our assessment is that the authors have improved the estimation of mean dietary sodium and potassium intakes. However, more work is needed to show that calibrated estimates actually improve estimation of future clinical events. If this methodological issue can be successfully addressed, their approach has the potential to improve estimation of dietary sodium and potassium intakes in observational studies., (© The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: According to traditional understanding of sodium homeostasis, nearly all of daily sodium intake is excreted in urine, with intraindividual variability attributed to variability in dietary sodium intake and urine collection errors., Objective: To analyze the variability of urinary sodium in excretion from a balance study with fixed sodium intakes., Methods: Daily 24-h urine collections were assessed for sodium, potassium, and creatinine in 22 black and 13 white adolescent girls (11-15 year, BMI 15-29 kg/m) in a randomized, crossover design with controlled diets containing either low (57 mmol/day) or high (167 mmol/day) sodium, each fed for 3 weeks., Results: Coefficient of variation analysis indicated higher variation in urinary sodium excretion about the mean on low (vs high) sodium (40 vs 32%, P = 0.02) and in black (vs white) girls (42 vs 30%, P < 0.001). A mixed model showed no sodium intake × race interaction. Urinary sodium excretion was not correlated with urinary potassium or creatinine excretion. Excretion of 65 mmol/day (adequate intake) or less was documented on 16% on the days during the high-sodium diet. Reliability of the mean of several urine sodium samples varied from 23% for one sample to 75% for 10 samples for the high-sodium diet., Conclusion: The high intraindividual variability in urinary sodium excretion on a fixed diet highlights the potential for substantial error in (a) using a single 24-h urine collection to estimate an individual's usual sodium intake and (b) relating sodium excretion from a single 24-h collection with outcomes. Further research is warranted to understand the causes of such variation.

Importance: Patients with chronic kidney disease (CKD) are at an increased risk of cardiovascular disease (CVD) compared with the general population. Prior studies have produced contradictory results on the association of dietary sodium intake with risk of CVD, and this relationship has not been investigated in patients with CKD., Objective: To evaluate the association between urinary sodium excretion and clinical CVD events among patients with CKD., Design, Setting, and Participants: A prospective cohort study of patients with CKD from 7 locations in the United States enrolled in the Chronic Renal Insufficiency Cohort Study and followed up from May 2003 to March 2013., Exposures: The cumulative mean of urinary sodium excretion from three 24-hour urinary measurements and calibrated to sex-specific mean 24-hour urinary creatinine excretion., Main Outcomes and Measures: A composite of CVD events defined as congestive heart failure, stroke, or myocardial infarction. Events were reported every 6 months and confirmed by medical record adjudication., Results: Among 3757 participants (mean age, 58 years; 45% women), 804 composite CVD events (575 heart failure, 305 myocardial infarction, and 148 stroke) occurred during a median 6.8 years of follow-up. From lowest (<2894 mg/24 hours) to highest (≥4548 mg/24 hours) quartile of calibrated sodium excretion, 174, 159, 198, and 273 composite CVD events occurred, and the cumulative incidence was 18.4%, 16.5%, 20.6%, and 29.8% at median follow-up. In addition, the cumulative incidence of CVD events in the highest quartile of calibrated sodium excretion compared with the lowest was 23.2% vs 13.3% for heart failure, 10.9% vs 7.8% for myocardial infarction, and 6.4% vs 2.7% for stroke at median follow-up. Hazard ratios of the highest quartile compared with the lowest quartile were 1.36 (95% CI, 1.09-1.70; P = .007) for composite CVD events, 1.34 (95% CI, 1.03-1.74; P = .03) for heart failure, and 1.81 (95% CI, 1.08-3.02; P = .02) for stroke after multivariable adjustment. Restricted cubic spline analyses of the association between sodium excretion and composite CVD provided no evidence of a nonlinear association (P = .11) and indicated a significant linear association (P < .001)., Conclusions and Relevance: Among patients with CKD, higher urinary sodium excretion was associated with increased risk of CVD., Competing Interests: Disclosures: All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr Steigerwalt reported having received support from Medtronic as a principal investigator for 2 trials and travel expenses from ATCOR. Dr Townsend reported having received support from Medtronic, Janssen, Relypsa, and UpToDate. No other disclosures were reported.

CKD is a major risk factor for ESRD, cardiovascular disease, and premature death. Whether dietary sodium and potassium intake affect CKD progression remains unclear. We prospectively studied the association of urinary sodium and potassium excretion with CKD progression and all-cause mortality among 3939 patients with CKD in the Chronic Renal Insufficiency Cohort Study. Urinary sodium and potassium excretion were measured using three 24-hour urine specimens, and CKD progression was defined as incident ESRD or halving of eGFR. During follow-up, 939 CKD progression events and 540 deaths occurred. Compared with the lowest quartile of urinary sodium excretion (<116.8 mmol/24 h), hazard ratios (95% confidence intervals) for the highest quartile of urinary sodium excretion (≥194.6 mmol/24 h) were 1.54 (1.23 to 1.92) for CKD progression, 1.45 (1.08 to 1.95) for all-cause mortality, and 1.43 (1.18 to 1.73) for the composite outcome of CKD progression and all-cause mortality after adjusting for multiple covariates, including baseline eGFR. Additionally, compared with the lowest quartile of urinary potassium excretion (<39.4 mmol/24 h), hazard ratios for the highest quartile of urinary potassium excretion (≥67.1 mmol/24 h) were 1.59 (1.25 to 2.03) for CKD progression, 0.98 (0.71 to 1.35) for all-cause mortality, and 1.42 (1.15 to 1.74) for the composite outcome. These data indicate that high urinary sodium and potassium excretion are associated with increased risk of CKD progression. Clinical trials are warranted to test the effect of sodium and potassium reduction on CKD progression., (Copyright © 2016 by the American Society of Nephrology.)

Objectives: Headaches are a common medical problem, yet few studies, particularly trials, have evaluated therapies that might prevent or control headaches. We, thus, investigated the effects on the occurrence of headaches of three levels of dietary sodium intake and two diet patterns (the Dietary Approaches to Stop Hypertension (DASH) diet (rich in fruits, vegetables and low-fat dairy products with reduced saturated and total fat) and a control diet (typical of Western consumption patterns))., Design: Randomised multicentre clinical trial., Setting: Post hoc analyses of the DASH-Sodium trial in the USA., Participants: In a multicentre feeding study with three 30 day periods, 390 participants were randomised to the DASH or control diet. On their assigned diet, participants ate food with high sodium during one period, intermediate sodium during another period and low sodium during another period, in random order., Outcome Measures: Occurrence and severity of headache were ascertained from self-administered questionnaires, completed at the end of each feeding period., Results: The occurrence of headaches was similar in DASH versus control, at high (OR (95% CI)=0.65 (0.37 to 1.12); p=0.12), intermediate (0.57 (0.29 to 1.12); p=0.10) and low (0.64 (0.36 to 1.13); p=0.12) sodium levels. By contrast, there was a lower risk of headache on the low, compared with high, sodium level, both on the control (0.69 (0.49 to 0.99); p=0.05) and DASH (0.69 (0.49 to 0.98); p=0.04) diets., Conclusions: A reduced sodium intake was associated with a significantly lower risk of headache, while dietary patterns had no effect on the risk of headaches in adults. Reduced dietary sodium intake offers a novel approach to prevent headaches., Trial Registration Number: NCT00000608., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Background: The 2010 Dietary Guidelines Advisory Committee report contained dietary patterns developed by using nutrient-dense foods. In most cases, low-sodium forms of foods were incorporated into the patterns., Objectives: We wanted to determine whether choosing lower-sodium foods could lower the sodium content to 1500 mg without compromising nutrient adequacy. We also explored the effect of choosing typical foods (more calories with higher sodium) and the feasibility of implementing sodium recommendations on a density basis (mg Na/kcal)., Design: Food patterns developed during the 2010 Dietary Guidelines development process were used as the base for this analysis. Modeling was then used to analyze the effect of substituting lower-sodium foods on nutrient adequacy., Results: Sodium amounts in the base model varied directly with energy level (1.0 mg Na/kcal) and ranged from 996 to 3176 mg/d. Amounts in the lowest-sodium model also varied with energy level (~0.5 mg/kcal) and ranged from 500 to 1250 mg/d. A comparison of sodium density for the base and the lowest sodium models showed that sodium in the lowest model is ~50% of the base. For typical food choices, sodium amounts were much higher (1.6-2.0 mg/kcal and 1715-5078 mg/d). Comparison of sodium density for the base and the typical food choice models showed that amounts were 1.6-2.0 times greater than the base., Conclusions: By choosing only low-sodium foods, it was possible to construct nutritionally adequate dietary patterns with 1500 mg Na/d. Sodium density (mg Na/kcal) is a practical approach for expressing sodium recommendations.

Background: While higher blood pressure is known to increase proteinuria, whether increased dietary sodium as estimated from 24-hour urinary excretion correlates with increased proteinuria in patients with chronic kidney disease (CKD) is not well studied., Methods: We measured 24-hour urinary sodium, potassium and protein excretion in 3,680 participants in the Chronic Renal Insufficiency Cohort study, to determine the relationship between urinary sodium and potassium and urinary protein excretion in patients with CKD. We stratified our data based on the presence or absence of diabetes given the absence of any data on this relationship and evidence that diabetics had greater urinary protein excretion at nearly every level of urinary sodium excretion. Multiple linear regressions were used with a stepwise inclusion of covariates such as systolic blood pressure, demographics, hemoglobin A1c and type of antihypertensive medications to evaluate the relationship between urinary electrolyte excretion and proteinuria., Results: Our data demonstrated that urinary sodium (+1 SD above the mean), as a univariate variable, explained 12% of the variation in proteinuria (β = 0.29, p < 0.0001), with rising urinary sodium excretion associated with increasing proteinuria. The significance of that relationship was only partially attenuated with adjustment for demographic and clinical factors and the addition of 24-hour urinary potassium to the model (β = 0.13, R(2) = 0.35, p < 0.0001)., Conclusions: An understanding of the relationship between these clinical factors and dietary sodium may allow a more tailored approach for dietary salt restriction in patients with CKD., (Copyright © 2012 S. Karger AG, Basel.)

Background: Inflammatory mediators regulate key aspects of lipid metabolism. We hypothesized that inflammation could diminish the cholesterol-lowering effect of a reduced-fat/low-cholesterol diet., Methods and Results: After a 2-week run-in period on a control diet (37% total fat, 16% saturated fat), 100 participants were randomized to the control or DASH diet (27% total fat, 6% saturated fat) for 12 weeks. Median C-reactive protein (CRP) at baseline was 2.37 mg/L (interquartile range, 1.20, 3.79). The DASH diet, net of control, had no effect on CRP. Overall, there were significant net reductions in total (-0.34 mmol/L), LDL (-0.29 mmol/L), and HDL (-0.12 mmol/L) cholesterol from the DASH diet (each, P<0.001) and little change in triglycerides (+0.05 mmol/L, P=0.21). Baseline CRP was strongly associated with lipid responsiveness to the DASH diet. Total and LDL cholesterol were reduced to a greater degree in those with a "low" (below median) compared with a "high" (above median) baseline CRP (total, -9.8% versus -3%; P for interaction=0.006; LDL cholesterol, -11.8% versus -3%; P for interaction=0.009). Reductions in HDL cholesterol (-8.8%) were similar in persons with low versus high CRP. Triglycerides were increased in those with a high CRP but not in those with a low CRP (19.8% versus +0%; P for interaction=0.019)., Conclusions: In this study, the presence of increased CRP was associated with less total and LDL cholesterol reduction and a greater increase in triglycerides from a reduced-fat/low-cholesterol diet. These findings document an additional mechanism by which inflammation might increase cardiovascular disease risk.

BackgroundUromodulin modulates the sodium-potassium-two-chloride transporter in the thick ascending limb of the loop of Henle, and its overexpression in murine models leads to salt-induced hypertension. We hypothesized that individuals with higher baseline levels of urine uromodulin would have a greater increase in systolic blood pressure (SBP) for the same increase in sodium compared with those with lower uromodulin levels.MethodsWe used data from 157 subjects randomized to the control diet of the Dietary Approaches to Stop Hypertension (DASH)-Sodium trial who were assigned to 30 days of low (1,500 mg/d), medium (2,400 mg/d), and high salt (3,300 mg/d) diets in random order. Blood pressure was measured prerandomization and then weekly during each feeding period. We evaluated the association of prerandomization urine uromodulin with change in SBP between diets, as measured at the end of each feeding period, using multivariable linear regression.ResultsBaseline urine uromodulin stratified by tertiles was ≤17.64, 17.65-31.97, and ≥31.98 µg/ml. Across the tertiles, there were no significant differences in SBP at baseline, nor was there a differential effect of sodium diet on SBP across tertiles (low to high, P = 0.81). After adjusting for age, sex, body mass index, and race, uromodulin levels were not significantly associated with SBP change from low to high sodium diet (P = 0.42).ConclusionsIn a randomized trial of different levels of salt intake, higher urine uromodulin levels were not associated with a greater increase in blood pressure in response to high salt intake.

ObjectivesTo determine the effect of sodium (Na) reduction on occurrence of headaches.MethodsIn the Trial of Nonpharmacologic Interventions in the Elderly, 975 men and woman (aged 60-80 years) with hypertension were randomized to a Na-reduction intervention or control group and were followed for up to 36 months. The study was conducted between 1992 and 1995 at 4 clinical centers (Johns Hopkins University, Wake Forest University School of Medicine, Robert Wood Johnson Medical School, and the University of Tennessee).ResultsMean difference in Na excretion between the Na-reduction intervention and control group was significant at each follow-up visit (P

Background: Salt substitution (ie, replacement of table and cooking salt with potassium-enriched salt substitutes) is a promising strategy to reduce blood pressure and prevent cardiovascular disease, particularly in countries like India where there is high sodium intake, mainly from discretionary salt, and low potassium intake. Life-threatening hyperkalemia from increased potassium intake is a postulated concern for individuals with chronic kidney disease.Methods: We used comparative risk assessment models to estimate the number of (1) cardiovascular deaths averted due to blood pressure reductions; (2) potential hyperkalemia-related deaths from increased potassium intake in individuals with advanced chronic kidney disease; and (3) net averted deaths from nationwide salt substitution in India. We evaluated a conservative scenario, based on a large, long-term pragmatic trial in rural China; and an optimistic scenario informed by our recent trial in India. Sensitivity analyses were conducted to assess the robustness of the findings.Results: In the conservative scenario, a nationwide salt substitution intervention was estimated to result in ≈214 000 (95% uncertainty interval, 92 764-353 054) averted deaths from blood pressure reduction in the total population and ≈52 000 (22 961-80 211) in 28 million individuals with advanced chronic kidney disease, while ≈22 000 (15 221-31 840) hyperkalemia-deaths might be caused by the intervention. The corresponding estimates for the optimistic scenario were ≈351 000 (130 470-546 255), ≈66 000 (24 925-105 851), and ≈9000 (4251-14 599). Net benefits were consistent across sensitivity analyses.Conclusions: Modeling nationwide salt substitution in India consistently estimated substantial net benefits, preventing around 8% to 14% of annual cardiovascular deaths. Even allowing for potential hyperkalemia risks there were net benefits estimated for individuals with chronic kidney disease. [ABSTRACT FROM AUTHOR]

Background Adherence to the Dietary Approaches to Stop Hypertension (DASH) diet enhances potassium intake and reduces sodium intake and blood pressure (BP), but the underlying metabolic pathways are unclear. Objectives Among free-living populations, we delineated metabolic signatures associated with the DASH diet adherence, 24-hour urinary sodium and potassium excretions, and the potential metabolic pathways involved. Methods We used 24-hour urinary metabolic profiling by proton nuclear magnetic resonance spectroscopy to characterize the metabolic signatures associated with the DASH dietary pattern score (DASH score) and 24-hour excretion of sodium and potassium among participants in the United States (n =  2164) and United Kingdom (n =  496) enrolled in the International Study of Macro- and Micronutrients and Blood Pressure (INTERMAP). Multiple linear regression and cross-tabulation analyses were used to investigate the DASH-BP relation and its modulation by sodium and potassium. Potential pathways associated with DASH adherence, sodium and potassium excretion, and BP were identified using mediation analyses and metabolic reaction networks. Results Adherence to the DASH diet was associated with urinary potassium excretion (correlation coefficient, r = 0.42; P  < 0.0001). In multivariable regression analyses, a 5-point higher DASH score (range, 7 to 35) was associated with a lower systolic BP by 1.35 mmHg (95% CI, −1.95 to −0.80 mmHg; P  = 1.2 × 10−5); control of the model for potassium but not sodium attenuated the DASH-BP relation. Two common metabolites (hippurate and citrate) mediated the potassium-BP and DASH-BP relationships, while 5 metabolites (succinate, alanine, S -methyl cysteine sulfoxide, 4-hydroxyhippurate, and phenylacetylglutamine) were found to be specific to the DASH-BP relation. Conclusions Greater adherence to the DASH diet is associated with lower BP and higher potassium intake across levels of sodium intake. The DASH diet recommends greater intake of fruits, vegetables, and other potassium-rich foods that may replace sodium-rich processed foods and thereby influence BP through overlapping metabolic pathways. Possible DASH-specific pathways are speculated but confirmation requires further study. INTERMAP is registered as NCT00005271 at www.clinicaltrials.gov. [ABSTRACT FROM AUTHOR]

Background: The blood pressure-lowering effects of the Dietary Approaches to Stop Hypertension (DASH) dietary pattern and reduced sodium intake are well established. The effects on other biomarkers related to vascular health are of interest and might assist in explaining the effects of the DASH diet and sodium reduction.Objectives: We hypothesized that a low-sodium DASH diet improves (lowers) biomarkers of inflammation [C-reactive protein (CRP) and soluble urokinase plasminogen activator receptor (suPAR)] and mineral metabolism [phosphorus and fibroblast growth factor-23 (FGF23)].Methods: We conducted a secondary analysis of the DASH-Sodium trial using frozen serum samples. This controlled feeding study randomly assigned 412 adults (≥22 y) with elevated blood pressure (120-159/80-95 mmHg) to consume either a DASH diet or control diet. Within each arm, participants received 3 sodium levels [low (1150 mg), intermediate (2300 mg), high (3450 mg)] in random sequence, each for 30 d. To maximize contrast, samples collected at the end of the low-sodium DASH (n = 198) and high-sodium control (n = 194) diets were compared. Between-diet differences in serum CRP, suPAR, phosphorus, and FGF23 concentrations were assessed using linear regression adjusted for age, sex, race, income, education, smoking status, and BMI.Results: CRP concentrations did not differ between groups (P = 0.83), but suPAR was higher after the low-sodium DASH diet than the high-sodium control [geometric mean 2470 pg/mL (95% CI: 2380, 2560 pg/mL), compared with 2290 pg/mL (95% CI: 2210, 2380 pg/mL); P = 0.006]. Phosphorus was higher after the low-sodium DASH diet [geometric mean 3.50 mg/dL (95% CI: 3.43, 3.57 mg/dL)] compared with the high-sodium control diet [geometric mean 3.39 mg/dL (95% CI: 3.33, 3.46 mg/dL); P = 0.04]. FGF23 was also higher after the low-sodium DASH diet [geometric mean 35.3 pg/mL (95% CI: 33.3, 37.3 pg/mL) compared with 28.2 pg/mL (95% CI: 26.6, 29.8 pg/mL); P < 0.001].Conclusions: Contrary to our hypothesis, biomarkers of inflammation and mineral metabolism were increased or unchanged by a low-sodium DASH diet compared with a high-sodium control diet in adults with elevated blood pressure. [ABSTRACT FROM AUTHOR]

BACKGROUND In the United States, current guidelines recommend a total sodium intake <2,300 mg/day, a guideline which does not consider kilocalorie intake. However, kilocalorie intake varies substantially by age and sex. We hypothesized that compared with sodium density, total sodium intake overestimates adherence to sodium recommendations, especially in adults consuming fewer kilocalories. METHODS In the National Health and Nutrition Examination Survey (NHANES), we estimated the prevalence of adherence to sodium intake recommendations (<2,300 mg/day) and corresponding sodium density intake (<1.1 mg/kcal = 2,300 mg at 2,100 kcal) by sex, age, race/ethnicity, and kilocalorie level. Adherence estimates were compared between the 2005–2006 (n = 5,060) and 2015–2016 (n = 5,266) survey periods. RESULTS In 2005–2006, 23.1% (95% confidence interval [CI]: 21.5, 24.9) of the US population consumed <2,300 mg of sodium/day, but only 8.5% (CI: 7.6, 9.4) consumed <1.1 mg/kcal in sodium density. In 2015–2016, these figures were 20.9% (CI: 18.8, 23.2) and 5.1% (CI: 4.4, 6.0), respectively. In 2015–2016, compared with 2005–2006, adherence by sodium density decreased more substantially (odds ratio = 0.59; CI: 0.48, 0.72; P < 0.001) than adherence by total sodium consumption (odds ratio = 0.85; CI: 0.73, 0.98; P = 0.03). The difference in adherence between total sodium and sodium density goals was greater among those with lower kilocalorie intake, namely, older adults, women, and Hispanic adults. CONCLUSIONS Adherence estimated by sodium density is substantially less than adherence estimated by total sodium intake, especially among persons with lower kilocalorie intake. Further efforts to achieve population-wide reduction in sodium density intake are urgently needed. [ABSTRACT FROM AUTHOR]

Two recent studies challenged traditional paradigms of mammalian sodium physiology, suggesting that sodium reduction might cause weight gain by altering metabolism. This new theory has important implications for population-wide dietary recommendations. However, these observations have not been confirmed. In the DASH (Dietary Approaches to Stop Hypertension)-Sodium trial, 412 adults with systolic blood pressure of 120 to 159 mm Hg and diastolic blood pressure of 80 to 95 mm Hg not taking antihypertensive medications were randomly assigned to the DASH diet or a control diet (parallel design). On their assigned diet, participants randomly consumed each of the 3 sodium levels for 4 weeks (crossover design). Participants were provided all meals but could drink noncaloric beverages (eg, water) freely. Throughout the trial, energy intake was adjusted to maintain weight constant. The 3 sodium levels (at 2100 kcal/day) were: low (1150 mg of Na/day), medium (2300 mg of Na/day), and high (3450 mg of Na/day). Energy intake, weight, self-reported thirst, and 24-hour urine volume were assessed after each period. Participants were 57% women and 57% black; mean age was 48 years [SD, 10]). Among those assigned the control, mean weight increased slightly with higher sodium but not among those assigned DASH. Energy intake did not vary across sodium levels in either diet (P-trends ≥0.36). Higher sodium resulted in more thirst (P-trends <0.001 on both diets) and higher urine volume (suggesting higher fluid intake) during the control diet (P-trend=0.007). Reducing sodium did not increase energy requirements to maintain stable weights but did decrease thirst and urine volume (control diet only), findings consistent with the traditional understanding of mammalian sodium physiology. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT00000608. [ABSTRACT FROM AUTHOR]

High salt (sodium chloride) intake raises blood pressure and increases the risk of developing hypertension, a major risk factor for cardiovascular disease. Little is known about salt intake in Nepal, and no study has estimated salt consumption from 24-hour urinary sodium excretion. Participants (n = 451) were recruited from the Community-Based Management of Non-Communicable Diseases in Nepal (COBIN) cohort in 2018. Salt intake was estimated by analyzing 24-hour urinary sodium excretion. Multivariate linear regression was used to estimate differences in salt intake. The mean (±SD) age and salt intake were 49.6 (±9.8) years and 13.3 (±4.7) g/person/d, respectively. Higher salt intake was significantly associated with male gender (β for female = -2.4; 95% CI: -3.3, -1.4) and younger age (β10 years  = -1.4; 95% CI: -1.4, -0.5) and higher BMI (β = 0.1; 95% CI: 0.0, 0.2). A significant association was also found between increase in systolic blood pressure and higher salt intake (β = 0.3; 95% CI: 0.0, 0.7). While 55% reported that they consumed just the right amount of salt, 98% were consuming more than the WHO recommended salt amount (<5 g/person/d). Daily salt intake in this population was over twice the limit recommended by the WHO, suggesting a substantial need to reduce salt intake in this population. It also supports the need of global initiatives such as WHO's Global Hearts Initiative SHAKE technical package and Resolves to Save Lives for sodium reduction in low- and middle-income countries like Nepal. [ABSTRACT FROM AUTHOR]

Dietary Na recommendations are expressed as absolute amounts (mg/d) rather than as Na density (mg/kcal). Our objective was to determine whether the strength of the relationship of Na intake with blood pressure (BP) varied with energy intake. The DASH (Dietary Approaches to Stop Hypertension)-Sodium trial was a randomized feeding trial comparing 2 diets (DASH and control) and 3 levels of Na density. Participants with pre- or stage 1 hypertension consumed diets for 30 days in random order; energy intake was controlled to maintain body weight. This secondary analysis of 379 non-Hispanic black and white participants used mixed-effects models to assess the association of Na and energy intakes with BP. The relationships between absolute Na and both systolic and diastolic BP varied with energy intake. BP rose more steeply with increasing Na at lower energy intake than at higher energy intake (P interaction<0.001). On the control diet with 2300 mg Na, both systolic and diastolic BP were higher (3.0 mm Hg; 95% confidence interval, 0.2-5.8; and 2.7 mm Hg; 95% confidence interval, 1.0-4.5, respectively) among those with lower energy intake (higher Na density) than among those with higher energy intake (lower Na density). The association of Na with systolic BP was stronger at lower levels of energy intake in both blacks and whites (P<0.001). The association of Na and diastolic BP varied with energy intake only among blacks (P=0.001). Sodium density should be considered as a metric for expressing dietary Na recommendations. [ABSTRACT FROM AUTHOR]

Both sodium reduction and the Dietary Approaches to Stop Hypertension (DASH) diet lower blood pressure (BP); however, the patterns of their effects on BP over time are unknown. In the DASH-Sodium trial, adults with pre-/stage 1 hypertension, not using antihypertensive medications, were randomly assigned to either a typical American diet (control) or DASH. Within their assigned diet, participants randomly ate each of 3 sodium levels (50, 100, and 150 mmol/d, at 2100 kcal) over 4-week periods. BP was measured weekly for 12 weeks; 412 participants enrolled (57% women; 57% black; mean age, 48 years; mean systolic BP [SBP]/diastolic BP [DBP], 135/86 mm Hg). For those assigned control, there was no change in SBP/DBP between weeks 1 and 4 on the high-sodium diet (weekly change, -0.04/0.06 mm Hg/week) versus a progressive decline in BP on the low-sodium diet (-0.94/-0.70 mm Hg/week; P interactions between time and sodium <0.001 for SBP and DBP). For those assigned DASH, SBP/DBP changed -0.60/-0.16 mm Hg/week on the high- versus -0.42/-0.54 mm Hg/week on the low-sodium diet (P interactions between time and sodium=0.56 for SBP and 0.10 for DBP). When comparing DASH to control, DASH changed SBP/DBP by -4.36/-1.07 mm Hg after 1 week, which accounted for most of the effect observed, with no significant difference in weekly rates of change for either SBP (P interaction=0.97) or DBP (P interaction=0.70). In the context of a typical American diet, a low-sodium diet reduced BP without plateau, suggesting that the full effects of sodium reduction are not completely achieved by 4 weeks. In contrast, compared with control, DASH lowers BP within a week without further effect thereafter.Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00000608. [ABSTRACT FROM AUTHOR]

Background: The relationship between lower sodium intake and total mortality remains controversial.Objectives: This study examined the relationship between well-characterized measures of sodium intake estimated from urinary sodium excretion and long-term mortality.Methods: Two trials, phase I (1987 to 1990), over 18 months, and phase II (1990 to 1995), over 36 months, were undertaken in TOHP (Trials of Hypertension Prevention), which implemented sodium reduction interventions. The studies included multiple 24-h urine samples collected from pre-hypertensive adults 30 to 54 years of age during the trials. Post-trial deaths were ascertained over a median 24 years, using the National Death Index. The associations between mortality and the randomized interventions as well as with average sodium intake were examined.Results: Among 744 phase I and 2,382 phase II participants randomized to sodium reduction or control, 251 deaths occurred, representing a nonsignificant 15% lower risk in the active intervention (hazard ratio [HR]: 0.85; 95% confidence interval [CI]: 0.66 to 1.09; p = 0.19). Among 2,974 participants not assigned to an active sodium intervention, 272 deaths occurred. There was a direct linear association between average sodium intake and mortality, with an HR of 0.75, 0.95, and 1.00 (references) and 1.07 (p trend = 0.30) for <2,300, 2,300 to <3,600, 3,600 to <4,800, and ≥4,800 mg/24 h, respectively; and with an HR of 1.12 per 1,000 mg/24 h (95% CI: 1.00 to 1.26; p = 0.05). There was no evidence of a J-shaped or nonlinear relationship. The HR per unit increase in sodium/potassium ratio was 1.13 (95% CI: 1.01 to 1.27; p = 0.04).Conclusions: We found an increased risk of mortality for high-sodium intake and a direct relationship with total mortality, even at the lowest levels of sodium intake. These results are consistent with a benefit of reduced sodium and sodium/potassium intake on total mortality over a 20-year period. [ABSTRACT FROM AUTHOR]

The article discusses the salt sensitivity of blood pressure which was stated that a physiological trait was presented animals used as models in research. Topics include the development of salt sensitivity in rats, the possible mechanics used to determine the salt sensitivity in blood pressure and the genetic factors and phenotype in rats.

Objectives. To determine the effect of sodium (Na) reduction on occurrence of headaches. Methods. In the Trial of Nonpharmacologic Interventions in the Elderly, 975 men and woman (aged 60-80 years) with hypertension were randomized to a Na-reduction intervention or control group and were followed for up to 36 months. The study was conducted between 1992 and 1995 at 4 clinical centers (Johns Hopkins University, Wake Forest University School of Medicine, Robert Wood Johnson Medical School, and the University of Tennessee). Results. Mean difference in Na excretion between the Na-reduction intervention and control group was significant at each follow-up visit (P < .001) with an average difference of 38.8 millimoles per 24 hours. The occurrence of headaches was significantly lower in the Na-reduction intervention group (10.5%) compared with control (14.3%) with a hazard ratio of 0.59 (95% confidence interval = 0.40, 0.88; P = .009). The risk of headaches was significantly associated with average level of Na excretion during follow-up, independent of most recent blood pressure. The relationship appeared to be nonlinear with a spline relationship and a knot at 150 millimoles per 24 hours. Conclusions. Reduced sodium intake, currently recommended for blood pressure control,may also reduce the occurrence of headaches in older persons with hypertension. [ABSTRACT FROM AUTHOR]

Background: For decades, dietary sodium intake in the United States has remained high, and few studies have examined strategies for maintaining recommended intakes. Objective: We examined the effects of a behavioral intervention, which emphasized spices and herbs, on the maintenance of sodium intake at the recommended intake of 1500 mg/d in individuals to whom the US Dietary Guidelines for Americans apply. Design: We conducted a 2-phase study that included adults ≥ 8 y of age for whom Dietary Guidelines for Americans recommends 1500 mg Na/d. The study was conducted in Baltimore, Maryland, from 2012 to 2014. In phase 1, 55 individuals consumed a low-sodium diet for 4 wk. Participants were provided all foods, snacks, and calorie-containing drinks. In phase 2, 40 participants from phase 1 were randomly assigned to either a behavioral intervention to reduce sodium intake (n = 20) or a self-directed control group (n = 20) for 20 wk. The primary study outcome was the change in mean 24-h urinary sodium excretion during phase 2. Linear regression analyses were used to determine intervention effects on urinary sodium excretion. Results: Participant characteristics were as follows: women: 65%; African American: 88%; hypertension: 63%; diabetes: 18%; mean age: 61 y; and mean body mass index (in kg/m2): 30. At the end of phase 2, mean 24-h sodium excretion was lower in the behavioral intervention than in the self-directed group (mean difference: 2956.8 mg/d; 95% CI: 21538.7, 2374.9 mg/d) after sodium intake at screening was controlled for (P = 0.002). These findings persisted in sensitivity analyses that excluded potentially incomplete urine collections [Mage’s equation mean difference: 21090 mg/d (P = 0.001); Joosens' equation mean difference: 2796 mg/d (P = 0.04)]. Conclusions: A multifactorial behavioral intervention emphasizing spices and herbs significantly reduced sodium intake. Because of the ubiquity of sodium in the US food supply, multilevel strategies addressing individual behaviors and the food supply are needed to improve adherence to recommendations. This trial was registered at clinicaltrials.gov as NCT01615159. [ABSTRACT FROM AUTHOR]

Recent reports of selected observational studies and a meta-analysis have stirred controversy and have become the impetus for calls to abandon recommendations for reduced sodium intake by the US general population. A detailed review of these studies documents substantial methodological concerns that limit the usefulness of these studies in setting, much less reversing, dietary recommendations. Indeed, the evidence base supporting recommendations for reduced sodium intake in the general population remains robust and persuasive. The American Heart Association is committed to improving the health of all Americans through implementation of national goals for health promotion and disease prevention, including its recommendation to reduce dietary sodium intake to <1500 mg/d. [ABSTRACT FROM AUTHOR]

Elevated blood pressure is a highly prevalent condition that is etiologically related to coronary heart disease and stroke, two of the leading causes of morbidity and mortality throughout the world. Excess salt (sodium chloride) intake is a major determinant of elevated blood pressure. In this article, we discuss the scientific rationale for population-wide salt reduction, the types and strength of available evidence, policy-making on dietary salt intake in the United States and other countries, and the role and impact of key stakeholders. We highlight a number of lessons learned, many of which are germane to policy development in other domains. [ABSTRACT FROM AUTHOR]

BackgroundEssential hypertension results from the interaction of several genetic and environmental factors. Identification of genetic factors that modulate blood pressure (BP) response to interventions can lead to improved strategies for prevention and control. The purpose of this study was to identify genes that modulate BP response to dietary interventions.MethodsWe used data and samples collected in two randomized feeding studies to determine the extent to which genetic architecture is associated with the effect on BP of sodium intake and the Dietary Approaches to Stop Hypertension (DASH) dietary pattern. Participants in both trials were adults with above-optimal BP or unmedicated stage 1 hypertension. Genomic DNA was typed for several candidate genes.ResultsThe effect of sodium intake on BP differed by genotype at the angiotensinogen, β2-adrenergic receptor, and kallikrein loci. The effect of DASH dietary pattern on BP differed by genotype at the β2-adrenergic receptor locus.ConclusionsThese findings have implications for understanding the mechanism(s) through which diet affects BP, the heterogeneity of these effects, and the extent to which dietary interventions can modulate genetic predisposition.American Journal of Hypertension (2011). doi:10.1038/ajh.2010.223 [ABSTRACT FROM AUTHOR]

Abstract: Public health campaigns in several countries encourage population-wide reduced sodium (salt) intake, but excessive intake remains a major problem. Excessive sodium intake is independently related to adverse blood pressure and is a key factor in the epidemic of prehypertension/hypertension. Identification of food sources of sodium in modern diets is critical to effective reduction of sodium intake worldwide. We used data from the INTERMAP Study to define major food sources of sodium in diverse East Asian and Western population samples. INTERMAP is an international, cross-sectional, epidemiologic study of 4, 680 individuals ages 40 to 59 years from Japan (four samples), People''s Republic of China (three rural samples), the United Kingdom (two samples), and the United States (eight samples); four in-depth, multipass 24-hour dietary recalls/person were used to identify foods accounting for most dietary sodium intake. In the People''s Republic of China sample, most (76%) dietary sodium was from salt added in home cooking, about 50% less in southern than northern samples. In Japan, most (63%) dietary sodium came from soy sauce (20%), commercially processed fish/seafood (15%), salted soups (15%), and preserved vegetables (13%). Processed foods, including breads/cereals/grains, contributed heavily to sodium intake in the United Kingdom (95%) and the United States (for methodological reasons, underestimated at 71%). To prevent and control prehypertension/hypertension and improve health, efforts to remove excess sodium from diets in rural China should focus on reducing salt in home cooking. To avoid excess sodium intake in Japan, the United Kingdom, and the United States, salt must be reduced in commercially processed foods. [Copyright &y& Elsevier]

Abstract: A substantial body of evidence has implicated several aspects of diet in the pathogenesis of elevated blood pressure (BP). Well-established risk factors for elevated BP include excess salt intake, low potassium intake, excess weight, high alcohol consumption, and suboptimal dietary pattern. African Americans are especially sensitive to the BP-raising effects of excess salt intake, insufficient potassium intake, and suboptimal diet. In this setting, dietary changes have the potential to substantially reduce racial disparities in BP and its consequences. In view of the age-related rise in BP in both children and adults, the direct, progressive relationship of BP with cardiovascular-renal diseases throughout the usual range of BP, and the worldwide epidemic of BP-related disease, efforts to reduce BP in nonhypertensive as well as hypertensive individuals are warranted. In nonhypertensives, dietary changes can lower BP and delay, if not prevent, hypertension. In uncomplicated stage I hypertension, dietary changes serve as initial treatment before drug therapy. In hypertensive individuals already on drug therapy, lifestyle modifications can further lower BP. The current challenge is designing and implementing effective clinical and public health interventions that lead to sustained dietary changes among individuals and more broadly in the general population. [Copyright &y& Elsevier]

Abstract: A substantial body of evidence has implicated several aspects of diet in the pathogenesis of elevated blood pressure (BP). Well-established risk factors for elevated BP include excess salt intake, low potassium intake, excess weight, high alcohol consumption, and suboptimal dietary pattern. African Americans are especially sensitive to the BP-raising effects of excess salt intake, insufficient potassium intake, and suboptimal diet. In this setting, dietary changes have the potential to substantially reduce racial disparities in BP and its consequences. In view of the age-related rise in BP in both children and adults, the direct, progressive relationship of BP with cardiovascular-renal diseases throughout the usual range of BP, and the worldwide epidemic of BP-related disease, efforts to reduce BP in nonhypertensive as well as hypertensive individuals are warranted. In nonhypertensives, dietary changes can lower BP and delay, if not prevent, hypertension. In uncomplicated stage I hypertension, dietary changes serve as initial treatment before drug therapy. In hypertensive individuals already on drug therapy, lifestyle modifications can further lower BP. The current challenge is designing and implementing effective clinical and public health interventions that lead to sustained dietary changes among individuals and more broadly in the general population. [Copyright &y& Elsevier]

The article discusses a study which concludes that a higher sodium to potassium excretion ratio is associated with increased risk of subsequent cardiovascular disease, with an effect that is stronger than that of sodium or potassium alone. Among adults who were not assigned to an active sodium reduction intervention, it assesses the relationship of a mean of three to seven 24 hour urinary excretions of sodium and potassium and their ratio with subsequent cardiovascluar disease. A model containing the sodium to potassium excretion ratio had the lowest Bayes information criterion.

Objectives: To assess contributions of individual lifestyle changes on systolic blood pressure (SBP) changes. Methods: We examined associations between lifestyle behavior changes and SBP after 6 and 18 months in 782 PREMIER trial participants. Results: In multivariate models omitting weight, predicted SBP reductions ranged from ½ to 1½ mm Hg for reduced urinary sodium, improved fitness, and adherence to the DASH diet (except sodium at 18 months). With weight included, only fitness change additionally predicted SBP at 18 months. Conclusions: Several lifestyle behavior changes are important for BP lowering, but are difficult to detect when weight is included in multivariate models. [ABSTRACT FROM AUTHOR]

Dietary strategies to prevent and treat osteoporosis focus on increased intake of calcium and vitamin D. Modification of whole dietary patterns and sodium reduction may also be effective. We examined the effects of two dietary patterns and three sodium levels on bone and calcium metabolism in a randomized feeding study. A total of 186 adults, aged 23-76 y, participated. After a 2-wk run-in period, participants were assigned randomly to diets containing three levels of sodium (50, 100 and 150 mmol/d) to be consumed for 30 d in random order. Serum osteocalcin (OC), C-terminal telopeptide of type I collagen (CTX), fasting serum parathyroid hormone (PTH), urinary sodium, potassium, calcium and cAMP were measured at baseline and at the end of each sodium period. The Dietary Approaches to Stop Hypertension (DASH) diet reduced serum OC by 8-11% and CTX by 16-18% (both P < 0.001). Urinary calcium excretion did not differ between subjects that consumed the DASH and control diets. Reducing sodium from the high to the low level significantly decreased serum OC 0.6 microg/L in subjects that consumed the DASH diet, fasting serum PTH 2.66 ng/L in control subjects and urinary calcium 0.5 mmol/24 h in both groups. There were no consistent effects of the diets or sodium levels on urinary cAMP. In conclusion, the DASH diet significantly reduced bone turnover, which if sustained may improve bone mineral status. A reduced sodium intake reduced calcium excretion in both diet groups and serum OC in the DASH group. The DASH diet and reduced sodium intake may have complementary, beneficial effects on bone health. [ABSTRACT FROM AUTHOR]

Dietary strategies to prevent and treat osteoporosis focus on increased intake of calcium and vitamin D. Modification of whole dietary patterns and sodium reduction may also be effective. We examined the effects of two dietary patterns and three sodium levels on bone and calcium metabolism in a randomized feeding study. A total of 186 adults, aged 23-76 y, participated. After a 2-wk run-in period, participants were assigned randomly to diets containing three levels of sodium (50, 100 and 150 mmol/d) to be consumed for 30 d in random order. Serum osteocalcin (CC), C-terminal telopeptide of type I collagen (CTX), fasting serum parathyroid hormone (PTH), urinary sodium, potassium, calcium and cAMP were measured at baseline and at the end of each sodium period. The Dietary Approaches to Stop Hypertension (DASH) diet reduced serum CC by 8-11% and CTX by 16-18% (both P < 0.001). Urinary calcium excretion did not differ between subjects that consumed the DASH and control diets. Reducing sodium from the high to the low level significantly decreased serum CC 0.6 µg/L in subjects that consumed the DASH diet, fasting serum PTH 2.66 ng/L in control subjects and urinary calcium 0.5 mmol/24 h in both groups. There were no consistent effects of the diets or sodium levels on urinary cAMP. In conclusion, the DASH diet significantly reduced bone turnover, which if sustained may improve bone mineral status. A reduced sodium intake reduced calcium excretion in both diet groups and serum CC in the DASH group. The DASH diet and reduced sodium intake may have complementary, beneficial effects on bone health. [ABSTRACT FROM AUTHOR]

Background: Initial findings from the Dietary Approaches to Stop Hypertension (DASH)-Sodium Trial demonstrated that reduction of sodium intake in two different diets decreased blood pressure in participants with and without hypertension. Objective: To determine effects on blood pressure of reduced sodium intake and the DASH diet in additional subgroups. Design: Randomized feeding study. Setting: Four clinical centers and a coordinating center. Participants: 412 adults with untreated systolic blood pressure of 120 to 160 mm Hg and diastolic blood pressure of 80 to 95 mm Hg. Intervention: Participants followed the DASH diet or a control (typical U.S.) diet for three consecutive 30-day feeding periods, during which sodium intake (50, 100, and 150 mmol/d at 2100 kcal) varied according to a randomly assigned sequence. Body weight was maintained. Measurements: Systolic and diastolic blood pressure. Results: In all subgroups, the DASH diet and reduced sodium intake were each associated with significant decreases in blood pressure; these two factors combined produced the greatest reductions. Among nonhypertensive participants who received the control diet, lower (vs. higher) sodium intake decreased blood pressure by 7.0/3.8 mm Hg in those older than 45 years of age (P< 0.001) and by 3.7/1.5 mm Hg in those 45 years of age or younger (P< 0.05). Conclusion: The DASH diet plus reduced sodium intake is recommended to control blood pressure in diverse subgroups. [ABSTRACT FROM AUTHOR]

The authors discuss the meta analysis on the relationship between sodium intake and cardiovascular disease (CVD). They cite studies that present study-specific methodological issues and evidence from randomized controlled trials on the association of low or high sodium intake to mortality. The authors mention the quality and heterogeneity of methodology used in assessing the relationship between salt intake and CVD.

The article discusses research conducted by E. Pimenta and colleagues on the effect of dietary sodium reduction in patients with resistant hypertension. The condition is defined as blood pressure (BP) above goal in spite using three antihypertensive agents of different classes. The study achieved the intended contrast in sodium intake and outcome variables which include ambulatory BP, pulse wave velocity measurements, and measurements of renin-angiotensin system activity.

Background: The DASH (Dietary Approaches to Stop Hypertension) diet has been determined to have beneficial effects on cardiac biomarkers. The effects of sodium reduction on cardiac biomarkers, alone or combined with the DASH diet, are unknown.Objectives: The purpose of this study was to determine the effects of sodium reduction and the DASH diet, alone or combined, on biomarkers of cardiac injury, strain, and inflammation.Methods: DASH-Sodium was a controlled feeding study in adults with systolic blood pressure (BP) 120 to 159 mm Hg and diastolic BP 80 to 95 mm Hg, randomly assigned to the DASH diet or a control diet. On their assigned diet, participants consumed each of three sodium levels for 4 weeks. Body weight was kept constant. At the 2,100 kcal level, the 3 sodium levels were low (50 mmol/day), medium (100 mmol/day), and high (150 mmol/day). Outcomes were 3 cardiac biomarkers: high-sensitivity cardiac troponin I (hs-cTnI) (measure of cardiac injury), N-terminal pro-B-type natriuretic peptide (NT-proBNP) (measure of strain), and high-sensitivity C-reactive protein (hs-CRP) (measure of inflammation), collected at baseline and at the end of each feeding period.Results: Of the original 412 participants, the mean age was 48 years; 56% were women, and 56% were Black. Mean baseline systolic/diastolic BP was 135/86 mm Hg. DASH (vs. control) reduced hs-cTnI by 18% (95% confidence interval [CI]: -27% to -7%) and hs-CRP by 13% (95% CI: -24% to -1%), but not NT-proBNP. In contrast, lowering sodium from high to low levels reduced NT-proBNP independently of diet (19%; 95% CI: -24% to -14%), but did not alter hs-cTnI and mildly increased hs-CRP (9%; 95% CI: 0.4% to 18%). Combining DASH with sodium reduction lowered hs-cTnI by 20% (95% CI: -31% to -7%) and NT-proBNP by 23% (95% CI: -32% to -12%), whereas hs-CRP was not significantly changed (-7%; 95% CI: -22% to 9%) compared with the high sodium-control diet.Conclusions: Combining a DASH dietary pattern with sodium reduction can lower 2 distinct mechanisms of subclinical cardiac damage: injury and strain, whereas DASH alone reduced inflammation. (Dietary Patterns, Sodium Intake and Blood Pressure [DASH - Sodium]; NCT00000608). [ABSTRACT FROM AUTHOR]