Systematic review of long term effects of advice to reduce dietary salt in adults

Burden of Hypertensive Heart Disease and High Systolic Blood Pressure in Australia from 1990 to 2019: Results From the Global Burden of Diseases Study

BACKGROUND

There is a dearth of comprehensive studies examining the burden and trends of hypertensive heart disease (HHD) and high systolic blood pressure (SBP) among the Australian population. We aimed to explore the burden of HHD and high SBP, and how they changed over time from 1990 to 2019 in Australia.

METHODS

We analysed data from the Global Burden of Disease study in Australia. We assessed the prevalence, mortality, disability-adjusted life-years (DALY), years lived with disability (YLD) and years of life lost (YLL) attributable to HHD and high SBP. Data were presented as point estimates with 95% uncertainty intervals (UI). We compared the burden of HHD and high SBP in Australia with World Bank defined high-income countries and six other comparator countries with similar sociodemographic characteristics and economies.

RESULTS

From 1990 to 2019, the burden of HHD and high SBP in Australia reduced. Age standardised prevalence rate of HHD was 119.3 cases per 100,000 people (95% UI 86.6-161.0) in 1990, compared to 80.1 cases (95% UI 57.4-108.1) in 2019. Deaths due to HDD were 3.4 cases per 100,000 population (95% UI 2.6-3.8) in 1990, compared to 2.5 (95% UI 1.9-3.0) in 2019. HHD contributed to 57.2 (95% UI 46.6-64.7) DALYs per 100,000 population in 1990 compared to 38.4 (95% UI 32.0-45.2) in 2019. Death rates per 100,000 population attributable to high SBP declined significantly over time for both sexes from 1990 (155.6 cases; 95% UI 131.2-177.0) to approximately one third in 2019 (53.8 cases; 95% UI 43.4-64.4). Compared to six other countries in 2019, the prevalence of HHD was highest in the USA (274.3%) and lowest in the UK (52.6%), with Australia displaying the third highest prevalence. Australia ranked second in term of lowest rates of deaths and third for lowest DALYs respectively due to high SBP. From 1990-2019, Australia ranked third best for reductions in deaths and DALYs due to HHD and first for reductions in deaths and DALYs due to high SBP.

CONCLUSION

Over the past three decades, the burden of HHD in Australia has reduced, but its prevalence remains relatively high. The contribution of high SBP to deaths, DALYs and YLLs also reduced over the three decades.

Hypertensive heart disease: risk factors, complications and mechanisms

Hypertensive heart disease constitutes functional and structural dysfunction and pathogenesis occurring primarily in the left ventricle, the left atrium and the coronary arteries due to chronic uncontrolled hypertension. Hypertensive heart disease is underreported and the mechanisms underlying its correlates and complications are not well elaborated. In this review, we summarize the current understanding of hypertensive heart disease, we discuss in detail the mechanisms associated with development and complications of hypertensive heart disease especially left ventricular hypertrophy, atrial fibrillation, heart failure and coronary artery disease. We also briefly highlight the role of dietary salt, immunity and genetic predisposition in hypertensive heart disease pathogenesis.

A comparison of paediatric hypertension clinical practice guidelines and their ability to predict adult hypertension in an African birth cohort

It remains unclear which paediatric hypertension clinical practice guideline (CPG) should be applied in an African population. We, therefore, aimed to compare commonly used CPG (2017 AAP, 2016 ESH, 2004 Fourth Report) developed in high-income countries for use in South African children at four paediatric ages (children: 5 years, 8 years; adolescents: 13 years, 17 years) to determine which best predicts elevated blood pressure (BP) in adulthood (22 years, 28 years). Moreover, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for each specific paediatric CPG was calculated across the age points. The 2017 AAP definition identified more children and adolescents with hypertension when compared to the 2004 Fourth Report and 2016 ESH guidelines. In computed hazards ratios, ages 8 years to 17 years, all three paediatric CPG significantly predicted the risk of elevated BP in young adulthood (p ≤ 0.032). However, sensitivity to predict elevated BP at age 22 years for all CPG was generally low (17.0%-33.0%) with higher specificity (87.4%-93.1%). Sensitivity increased at age 28 years (51.4%-70.1%), while specificity decreased (52.8%-65.1%). Both PPV and NPV at both adult age points varied widely (17.9%-79.9% and 29.3%-92.5% respectively). The performance of these paediatric CPG in terms of AUC were not optimal at both adult age points, however, the 2017 AAP definition at age 17 years met an acceptable level of performance (AUC = 0.71). Our results, therefore, highlight the need for more research to examine if an African-specific CPG would better identify high-risk children to minimise their trajectory towards adult hypertension.

The effect of a low versus high sodium diet on blood pressure in diabetic patients: A systematic review and meta‐analysis of clinical trials

There have been numerous clinical trials that have investigated the effect of sodium intake on blood pressure in diabetic patients. The purpose of this systematic review and meta-analysis was to evaluate the clinical trial studies performed on the effect of low sodium diet (LSD) versus high sodium diet (HSD) on blood pressure in diabetic patients. PubMed, Scopus, and Web of Science were systematically searched from database inception to July 10, 2021. Both type 1 and 2 diabetes was considered. Overall, there were 15 studies included in this meta-analysis. The weighted (WMD) mean difference with 95% confidence interval (CI) was calculated using a random-effects model. Risk of bias in the studies was assessed based on the Cochrane collaboration tool and the quality of all the studies was considered as good. Overall, LSD significantly reduced SBP (systolic blood pressure) (WMD: -3.79 mmHg, 95% CI: -6.02, -1.56) and DBP (diastolic blood pressure) (WMD: -1.62 mmHg, 95% CI: -2.84, -0.40), in comparison with HSD, in diabetics. However, LSD had no significant effect on MAP (mean arterial pressure) in comparison with HSD (WMD: -1.81, 95%CI: -5.49, 1.87). Although subgroup analysis could not attenuate heterogeneity in SBP, subgroup analysis in DBP based on duration (≤1 week: WMD: -2.35, 95%CI: -3.69, -1.00, I ²  = 48.9%, p = 0.081, >1 week: WMD: -1.04, 95% CI: -2.83, 0.76, I ²  = 74.7%, p = 0.003) and study design (cross-over: WMD: -1.94, 95% CI: -2.71, -1.17, I ²  = 32.1%, p = 0.183, parallel: WMD: -2.17, 95% CI: -6.48, 2.13, I ²  = 82.4%, p = 0.001) successfully detected sources of heterogeneity. LSD significantly reduced SBP and DBP, however, had no effect on MAP, in comparison with HSD.

Association between Indoor Temperature in Winter and Serum Cholesterol: A Cross-Sectional Analysis of the Smart Wellness Housing Survey in Japan

AIM

Issuance of the WHO Housing and health guidelines has paralleled growing interest in the housing environment. Despite accumulating evidence of an association between outdoor temperature and serum cholesterol, indoor temperature has not been well investigated. This study examined the association between indoor temperature and serum cholesterol.

METHODS

We collected valid health checkup data of 2004 participants (1333 households), measured the indoor temperature for 2 weeks in winter, and divided participants according to whether they lived in a warm (average bedroom temperature ≥ 18℃), slightly cold (12-18℃) or cold house (＜12˚C). The relationship between bedroom temperature and serum cholesterol was analyzed using multivariate logistic regression models, adjusting for demographics, lifestyle habits and the season in which the health checkup was conducted, with a random effect of climate areas in Japan.

RESULTS

The sample sizes for warm, slightly cold, and cold houses were 206, 940, and 858, respectively. Compared to those in warm houses, the odds ratio of total cholesterol exceeding 220 mg/dL was 1.83 (95%CI: 1.23-2.71, p=0.003) for participants in slightly cold houses and 1.87 (95%CI: 1.25-2.80, p=0.002) in cold houses. Similarly, the odds ratio of LDL/non-HDL cholesterol exceeding the standard range was 1.49 (p=0.056)/1.67 (p=0.035) for those in slightly cold houses and 1.64 (p=0.020)/1.77 (p=0.021) in cold houses. HDL cholesterol and triglycerides were not significantly associated with bedroom temperature.

CONCLUSION

Besides lifestyle modification, improving indoor thermal environment through strategies such as installing high thermal insulation and appropriate use of heating devices may contribute to better serum cholesterol condition.

Implementation of non-pharmacological interventions for the treatment of hypertension in primary care: a narrative review of effectiveness, cost-effectiveness, barriers, and facilitators

BACKGROUND

The current guidelines for the prevention, detection, evaluation, and management of hypertension recommend six types of non-pharmacological interventions: alcohol reduction, salt intake reduction, increased potassium intake, physical activity, weight loss, and heart-healthy diets. However, the non-pharmacological interventions are still not widely used in primary care. In this paper, we, therefore, reviewed and summarised the evidence on the effectiveness, cost-effectiveness, barriers, and facilitators of non-pharmacological interventions for the treatment of hypertension in primary care.

METHODS

A thorough literature search was conducted in Embase, Google Scholar, and PubMed databases, to identify the most recent reviews or, in their absence, primary studies on alcohol reduction, salt intake reduction, potassium supplementation, physical activity, weight reduction, heart-healthy diets, and other non-pharmacological interventions for the treatment of hypertension in primary care.

RESULTS

Alcohol reduction is a non-pharmacological intervention for the treatment of hypertension in primary care with proven effectiveness, feasibility, and acceptability. Interventions for sodium intake reduction, physical activity, and weight reduction are effective but there is insufficient evidence regarding their feasibility and acceptability in primary care settings. Evidence on the effectiveness of potassium intake and heart-healthy diets is limited and inconsistent. There is a lack of evidence on the cost-effectiveness of non-pharmacological interventions in the treatment of hypertension. The most common barriers to deliver such interventions related to healthcare providers include a lack of time, knowledge, self-confidence, resources, clear guidelines, and financial incentives. The most common barriers related to patients include a lack of motivation and educational resources. Less evidence is available on facilitators of implementing non-pharmacological interventions in primary care. Besides, facilitators differed by different types of interventions.

CONCLUSIONS

Available evidence suggests that more pragmatic, clinically feasible, and logistically simple interventions are required for sodium intake reduction, physical activity, and weight reduction in primary care settings. Future studies should provide further evidence on the effectiveness of weight control, potassium intake, and heart-healthy diets. More research is also needed on cost-effectiveness and facilitators of all types of effective non-pharmacological interventions for the treatment of hypertension in primary care.

Survey of the salt (NaCl) Contents of Traditional Breads in Tehran, 2016‒2018: Implication for Public Health

Background

Considering the importance of non-communicable diseases (NCDs) in Iran, the aim of this study is to identify the trend in the salt (NaCl) levels of various types of traditional bread (sangak, barbari, taftoon, and lavash breads) in Tehran in 2016 and 2018 and its implication for public health.

Methods

A total of 777 samples of various traditional breads were randomly collected from various districts located in Tehran in 2018. The salt content (expressed as g/100 g dry weight) in these breads were determined according to Volhard method. Results from this study were compared with those reported in 2016.

Results

The present study indicated that the mean salt content in traditional breads in 2018 was significantly higher than that reported in 2016. Salt content in traditional breads collected in 2018 ranged from 0.03 to 6.52/100 g dry weight, with mean value of 1.43 g/100 g dry weight. When comparing with the permitted limit set by Institute of Standards and Industrial Research of Iran (ISIRI), there was an increase in the percentage of samples complying with the permitted limit; 50.8% (2016) vs 54.1% (2018).

Conclusions

The daily salt intake increased from 1.56 g per person in 2016 to 2.31 g per person in 2018. Considering the high bread per capita consumption in Iran, it seems that half of the daily recommended salt intake could be reached exclusively through breads. Hence, the main strategies for salt intake reduction from bread could be achieved through evaluation of salt reduction programs and development of technological factors in bread baking.

Short-term effects of modest salt reduction combined with DASH diet on changing salt eating habits in hypertensive patients with type II diabetes

OBJECTIVE

Excessive salt intake is currently the foremost universal risk factor for controllable chronic disease. This study evaluated the short-term effects of a modest salt intake reduction combined with the Chinese Modified Dietary Approaches to Stop Hypertension (CM-DASH) diet on sodium and potassium intake, mean arterial pressure (MAP), and pulse pressure (PP) in hypertensive patients with type II diabetes.

METHODS

Sixty-one participants were randomized to the intervention group (52% low-sodium salt and DASH) and control group (normal salt and DASH). An 8-week dietary intervention was applied. Daily salt intake, blood pressure (BP), and drug use were recorded every week. Twenty-four-hour urine, casual urine, and blood samples were measured at baseline, the 4th week, and the end of the intervention.

RESULTS

Fifty-nine patients (25 men) completed the entire study. Sodium intake decreased by 1259.66 (792.76, 1726.56)/705.80 (149.21, 1262.39) mg/day after 4 weeks (intervention: P < .001; control: P = .015). Potassium intake increased by 641.14 (73.31, 1208.96)/43.43 (-259.66, 346.53) mg/day (intervention: P = .028); MAP decreased by 9.06 (6.69, 11.43)/7.16 (4.03, 10.28) mmHg (both: P < .001); PP decreased by 7.97 (3.05, 12.88)/5.74 (2.55,8.94) mmHg (intervention: P = .002; control: P = .001) after 8 weeks. However, the difference between the two groups was not statistically significant.

CONCLUSION

Modest salt reduction and the CM-DASH diet for hypertensive patients with type II diabetes can achieve short-term salt reduction effects. The effect on changing salt-eating habits needs to be investigated with an extended follow-up.

Using Digital Platform Approach to Reduce Salt Intake in a Sample of UAE Population: An Intervention Study

Background

Non-communicable diseases (NCDs) are the leading causes of mortality globally, accounting for more deaths than all other causes combined. World Health Organization launched its initiative in 2013 to reduce the intake of salt, the number of countries that have national sodium reduction strategies reached to 89 countries in 2017. In 2020, a study conducted in UAE showed more than 65% of the population exceeded WHO recommendations for salt intake. This study aimed to measure effectiveness of using digital platform approach to deliver educational materials to facilitate salt reduction in a sample of UAE population.

Methods

A controlled parallel intervention study was conducted in 2020. A sample of 121 participants completed the study and fulfilled the inclusion criteria with female to male ratio of (0.95:1.05). Participants were distributed randomly into three groups Control group, WhatsApp group, and Electronic Brochures group. Educational materials were distributed among participants of WhatsApp and Electronic brochures groups for 6-weeks. 24-h urinary excretion for sodium, potassium and creatinine, were measured in addition to KAP questionnaire and physical activity on two occasions at baseline and endpoint after 10-weeks (6-weeks of educational intervention).

Results

Both intervention groups showed a reduction in sodium with 278 mg (p < 0.001) for WhatsApp group (n = 41) and 169 mg (p < 0.018) for Electronic brochures group (n = 41), while Control group didn't show any significant change. Moreover, the percentage of participants exceeding WHO recommendation of sodium intake was significantly reduced at the end of intervention, (p = 0.004). WhatsApp group was more efficient in the percentage of reduction of participants exceeding WHO recommendation compared with baseline, with p = 0.023. A significant reduction in the practice toward adding salt during cooking, use of table salt, adding salt before tasting the foods and use of chicken stocks for both intervention groups was noted with p < 0.05. Intervention groups showed a significant improvement (p < 0.001) in Food and Health related knowledge after 6-weeks of intervention.

Conclusion

The digital platform approach such as WhatsApp and Electronic Brochure were effective in salt reduction. This study proves that UAE population is ready to reduce salt intake with appropriate education materials and easy delivery approach.

Effects of Within-Person Variability in Spot Urinary Sodium Measurements on Associations With Blood Pressure and Cardiovascular Disease

Randomized trials of salt restriction have consistently demonstrated that decreasing salt consumption lowers blood pressure, but results of observational studies of salt intake and cardiovascular disease have been conflicting. After excluding individuals with prevalent cardiovascular or kidney disease in the prospective UK Biobank study, we examined the within-person variability in spot urinary sodium excretion and its impact on associations with systolic blood pressure and risk of incident cardiovascular disease. Spearman correlation coefficients were used to assess within-person variability in spot urinary sodium, and associations between sodium and blood pressure were assessed using linear regression in participants with measurements at baseline (N=355 134) and after 9 years (N=33 915). Cox regression was used to assess associations with the risk of cardiovascular disease over the same follow-up period (N=5566 events). The within-person variability in urinary sodium was extreme, with a self-correlation coefficient of 0.35 over 4 years. Each 100 mmol/L higher usual urinary sodium was associated with 3.09 mm Hg higher systolic blood pressure (95% CI, 2.7–3.48) at baseline, but had no association at 9 years (0.97 [−0.44 to 2.37]). Likewise, there was no association between urinary sodium and risk of cardiovascular disease over the same follow-up period (hazard ratio, 1.05, [0.87–1.26]). While spot urinary sodium measurements were associated with immediate effects on blood pressure at baseline, the extreme within-person variability in urinary sodium precluded detection of associations with future blood pressure at resurvey or risk of cardiovascular disease. The limitations of observational studies, irrespective of study size, should be recognized when assessing public policy on salt restriction.

Electrocardiogram abnormalities in residents in cold homes: a cross-sectional analysis of the nationwide Smart Wellness Housing survey in Japan

Background

Excess winter mortality caused by cardiovascular disease is particularly profound in cold houses. Consistent with this, accumulating evidence indicates that low indoor temperatures at home increase blood pressure. However, it remains unclear whether low indoor temperatures affect other cardiovascular biomarkers. In its latest list of priority medical devices for management of cardiovascular diseases, the World Health Organization (WHO) included electrocardiography systems as capital medical devices. We therefore examined the association between indoor temperature and electrocardiogram findings.

Methods

We collected electrocardiogram data from 1480 participants during health checkups. We also measured the indoor temperature in the living room and bedroom for 2 weeks in winter, and divided participants into those living in warm houses (average exposure temperature ≥ 18 °C), slightly cold houses (12–18 °C), and cold houses (< 12 °C) in accordance with guidelines issued by the WHO and United Kingdom. The association between indoor temperature (warm vs. slightly cold vs. cold houses) and electrocardiogram findings was analyzed using multivariate logistic regression models, with adjustment for confounders such as demographics (e.g., age, sex, body mass index, household income), lifestyle (e.g., eating habit, exercise, smoking, alcohol drinking), and region.

Results

The average temperature at home was 14.7 °C, and 238, 924, and 318 participants lived in warm, slightly cold, and cold houses, respectively. Electrocardiogram abnormalities were observed in 17.6%, 25.4%, and 30.2% of participants living in warm, slightly cold, and cold houses, respectively (p = 0.003, chi-squared test). Compared to participants living in warm houses, the odds ratio of having electrocardiogram abnormalities was 1.79 (95% confidence interval: 1.14–2.81, p = 0.011) for those living in slightly cold houses and 2.18 (95% confidence interval: 1.27–3.75, p = 0.005) for those living in cold houses.

Conclusions

In addition to blood pressure, living in cold houses may have adverse effects on electrocardiogram. Conversely, keeping the indoor thermal environment within an appropriate range through a combination of living in highly thermal insulated houses and appropriate use of heating devices may contribute to good cardiovascular health.

Trial registration

The trial was retrospectively registered on 27 Dec 2017 to the University hospital Medical Information Network Clinical Trials Registry (UMIN-CTR, https://www.umin.ac.jp/ctr/, registration identifier number UMIN000030601).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12199-021-01024-1.

Decreasing Salt in Hospital Meals Reduced Energy Intake in Elderly Japanese Inpatients

Japanese salt consumption is high, about 10 g salt/d. Low salt intake reduces the risk of hypertension and cardiovascular disease. However, saltiness is an important taste in daily meals, greatly influencing eating habits. When hospital admission is short-term, reducing salt supply may have an adverse effect on food intake. The aim of this study is to find the effect of sudden change in dietary salt content on energy intake in elderly Japanese inpatients. The study is an observational study of 83 patients and was conducted in a hospital in Tokyo, Japan. The research period was three weeks, and included 8 g salt/d meals for the 1st week, 7 g salt/d meals for the 2nd week, and 7 g salt/d meals with total 1 g/d salt packs that patients were allowed to use freely for the 3rd week. The energy supply satisfied the individuals' energy requirements and was the same throughout the three weeks. Nutrition surveys and blood pressure measurements during the three weeks were conducted by dietitians and nurses, respectively. The results showed that energy intake of patients was reduced by about 90 kcal/d in the 2nd week compared with the 1st week and increased about 130 kcal/d in the 3rd week compared with the 2nd week. Blood pressure did not change during the research period. When high salt intake has become a habit, reducing salt supply suddenly in a short time period may lead to decreased energy intake in elderly inpatients but does not affect blood pressure.

Altered dietary salt intake for people with chronic kidney disease

BACKGROUND

Evidence indicates that reducing dietary salt may reduce the incidence of heart disease and delay decline in kidney function in people with chronic kidney disease (CKD). This is an update of a review first published in 2015.

OBJECTIVES

To evaluate the benefits and harms of altering dietary salt for adults with CKD.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 6 October 2020 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials comparing two or more levels of salt intake in adults with any stage of CKD.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for eligibility, conducted risk of bias evaluation and evaluated confidence in the evidence using GRADE. Results were summarised using random effects models as risk ratios (RR) for dichotomous outcomes or mean differences (MD) for continuous outcomes, with 95% confidence intervals (CI).

MAIN RESULTS

We included 21 studies (1197 randomised participants), 12 in the earlier stages of CKD (779 randomised participants), seven in dialysis (363 randomised participants) and two in post-transplant (55 randomised participants). Selection bias was low in seven studies, high in one and unclear in 13. Performance and detection biases were low in four studies, high in two, and unclear in 15. Attrition and reporting biases were low in 10 studies, high in three and unclear in eight. Because duration of the included studies was too short (1 to 36 weeks) to test the effect of salt restriction on endpoints such as death, cardiovascular events or CKD progression, changes in salt intake on blood pressure and other secondary risk factors were examined. Reducing salt by mean -73.51 mmol/day (95% CI -92.76 to -54.27), equivalent to 4.2 g or 1690 mg sodium/day, reduced systolic/diastolic blood pressure by -6.91/-3.91 mm Hg (95% CI -8.82 to -4.99/-4.80 to -3.02; 19 studies, 1405 participants; high certainty evidence). Albuminuria was reduced by 36% (95% CI 26 to 44) in six studies, five of which were carried out in people in the earlier stages of CKD (MD -0.44, 95% CI -0.58 to -0.30; 501 participants; high certainty evidence). The evidence is very uncertain about the effect of lower salt intake on weight, as the weight change observed (-1.32 kg, 95% CI -1.94 to -0.70; 12 studies, 759 participants) may have been due to fluid volume, lean tissue, or body fat. Lower salt intake may reduce extracellular fluid volume in the earlier stages of CKD (-0.87 L, 95% CI -1.17 to -0.58; 3 studies; 187 participants; low certainty evidence). The evidence is very uncertain about the effect of lower salt intake on reduction in antihypertensive dose (RR 2.45, 95% CI 0.98 to 6.08; 8 studies; 754 participants). Lower salt intake may lead to  symptomatic hypotension (RR 6.70, 95% CI 2.40 to 18.69; 6 studies; 678 participants; moderate certainty evidence). Data were sparse for other types of adverse events.

AUTHORS' CONCLUSIONS

We found high certainty evidence that salt reduction reduced blood pressure in people with CKD, and albuminuria in people with earlier stage CKD in the short-term. If such reductions could be maintained long-term, this effect may translate to clinically significant reductions in CKD progression and cardiovascular events. Research into the long-term effects of sodium-restricted diet for people with CKD is warranted.

Assessing the Impact of Salt Reduction Initiatives on the Chronic Disease Burden of Singapore

Globally, many countries are facing an increasing burden of chronic disease due to ageing populations, of which cardiovascular disease forms a large proportion. Excess dietary sodium contributes to cardiovascular disease risk and requires intervention at a population level. This study aimed to quantify the impact of several salt reduction initiatives on population health over a 30-year horizon using GeoDEMOS, a population model from Singapore. Four interventions were modelled in four demographic groups in 2020 for a total of 16 intervention scenarios. The effect of 0.5, 2.0, and 4.0 g/day reductions in daily salt consumption, along with adherence to the World Health Organization guidelines of a maximum of 5.0 g of salt each day, was modelled in the entire population, including the overweight and obese, the elderly, and diabetics. In each scenario, the number of averted incident cases of acute myocardial infarction and stroke, along with the disability-adjusted life years up to 2050, was monitored. We found 4.0 g/day reductions in salt consumption were the most effective when implemented across the entire population, resulting in 24,000 averted incident cases of cardiovascular disease and 215,000 disability-adjusted life years over 30 years. This is a large figure when compared with the 29,200 projected annual incident cases of cardiovascular disease in 2050. When targeted at specific high-risk demographic groups, the largest effects were observed in the overweight and obese, with the same intervention yielding 10,500 averted incident cases of cardiovascular disease and 91,500 disability-adjusted life years. Quantifying the benefits of salt reduction initiatives revealed a significant impact when administered across the entire population or the overweight and obese. Health promotion efforts directed toward sustainably reducing salt consumption will help to lower the chronic disease burden on the healthcare system in years to come.

The role of dietary salt and alcohol use reduction in the management of hypertension

Introduction: Despite the improved treatment protocol of hypertension, the magnitude of the disease and its related burden remains raised. Hypertension makes up the leading cause of stroke, kidney disease, arterial disease, eye disease, and cardiovascular disease (CVD) growth. Areas covered: This review provides the overview of the role of dietary salt and alcohol use reduction in the management of hypertension, a brief history of alcohol, the vascular endothelium functions, the effects of alcohol use on blood pressure (BP), the mechanisms of alcohol, brief history of salt, the effects of dietary salt intake on BP, and the mechanisms of salt. Expert opinion: Studies found that high dietary salt intake and heavy alcohol consumption have a major and huge impact on BP while both of them have been identified to increase BP. Also, they raise the risk of hypertension-related morbidity and mortality in advance. On the other way, the dietary salt and alcohol use reduction in the management of hypertension are significant in the control of BP and its related morbidity and mortality. Further, studies suggested that the dietary salt and alcohol use reductions are the cornerstone in the management of hypertension due to their significance as part of comprehensive lifestyle modifications.

Excessive maternal salt intake gives rise to vasopressin-dependent salt sensitivity of blood pressure in male offspring

Salt sensitivity of blood pressure (SSBP) is a trait carrying strong prognostic implications for various cardiovascular diseases. To test the hypothesis that excessive maternal salt intake causes SSBP in offspring through a mechanism dependent upon arginine-vasopressin (AVP), we performed a series of experiments using offspring of the rat dams salt-loaded during pregnancy and lactation with 1.5% saline drink ("experimental offspring") and those with normal perinatal salt exposure ("control offspring"). Salt challenge, given at 7-8 weeks of age with either 2% saline drink (3 days) or 8% NaCl-containing chow (4 weeks), had little or no effect on systolic blood pressure (SBP) in female offspring, whereas the salt challenge significantly raised SBP in male offspring, with the magnitude of increase being greater in experimental, than control, rats. Furthermore, the salt challenge not only raised plasma AVP level more and caused greater depressor responses to V1a and V2 AVP receptor antagonists to occur in experimental, than control, males, but it also made GABA excitatory in a significant proportion of magnocellular AVP neurons of experimental males by depolarizing GABA equilibrium potential. The effect of the maternal salt loading on the salt challenge-elicited SBP response in male offspring was precluded by maternal conivaptan treatment (non-selective AVP receptor antagonist) during the salt-loading period, whereas it was mimicked by neonatal AVP treatment. These results suggest that the excessive maternal salt intake brings about SSBP in male offspring, both the programming and the expression of which depend on increased AVP secretion that may partly result from excitatory GABAergic action.

Effects of the Dietary Approaches to Stop Hypertension Diet and Sodium Reduction on Blood Pressure in Persons With Diabetes

Elevated blood pressure and blood pressure-related morbidity are extraordinarily common in persons with diabetes. The Dietary Approaches to Stop Hypertension dietary pattern and dietary sodium reduction are recommended as lifestyle interventions in individuals with diabetes. However, these recommendations have largely been based on studies conducted in persons without diabetes. In this review, we summarize available evidence from trials that tested the effects of these 2 dietary interventions on blood pressure in people with diabetes. Overall, of the 3 trials (total n=151) that tested the effects of the Dietary Approaches to Stop Hypertension dietary pattern in persons with diabetes, 2 trials documented that the Dietary Approaches to Stop Hypertension dietary pattern lowered blood pressure. While 16 trials (total n=445) tested the effects of sodium reduction in persons with diabetes, results were inconsistent, likely because of design limitations, for example, brief duration, small sample size, and low baseline blood pressure levels, as well as differences in the mode of intervention delivery (behavioral interventions, feeding studies, and sodium supplements). In conclusion, there is a substantial need for additional research on the blood pressure lowering effects of the Dietary Approaches to Stop Hypertension diet and sodium reduction in people with diabetes and hypertension, given the high prevalence of hypertension and the dearth of high-quality trials in this population.

Effects of low sodium diet versus high sodium diet on blood pressure, renin, aldosterone, catecholamines, cholesterol, and triglyceride

BACKGROUND

Recent cohort studies show that salt intake below 6 g is associated with increased mortality. These findings have not changed public recommendations to lower salt intake below 6 g, which are based on assumed blood pressure (BP) effects and no side-effects.

OBJECTIVES

To assess the effects of sodium reduction on BP, and on potential side-effects (hormones and lipids) SEARCH METHODS: The Cochrane Hypertension Information Specialist searched the following databases for randomized controlled trials up to April 2018 and a top-up search in March 2020: the Cochrane Hypertension Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (from 1946), Embase (from 1974), the World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.gov. We also contacted authors of relevant papers regarding further published and unpublished work. The searches had no language restrictions. The top-up search articles are recorded under "awaiting assessment."

SELECTION CRITERIA

Studies randomizing persons to low-sodium and high-sodium diets were included if they evaluated at least one of the outcome parameters (BP, renin, aldosterone, noradrenalin, adrenalin, cholesterol, high-density lipoprotein, low-density lipoprotein and triglyceride,.

DATA COLLECTION AND ANALYSIS

Two review authors independently collected data, which were analysed with Review Manager 5.3. Certainty of evidence was assessed using GRADE.

MAIN RESULTS

Since the first review in 2003 the number of included references has increased from 96 to 195 (174 were in white participants). As a previous study found different BP outcomes in black and white study populations, we stratified the BP outcomes by race. The effect of sodium reduction (from 203 to 65 mmol/day) on BP in white participants was as follows: Normal blood pressure: SBP: mean difference (MD) -1.14 mmHg (95% confidence interval (CI): -1.65 to -0.63), 5982 participants, 95 trials; DBP: MD + 0.01 mmHg (95% CI: -0.37 to 0.39), 6276 participants, 96 trials. Hypertension: SBP: MD -5.71 mmHg (95% CI: -6.67 to -4.74), 3998 participants,88 trials; DBP: MD -2.87 mmHg (95% CI: -3.41 to -2.32), 4032 participants, 89 trials (all high-quality evidence). The largest bias contrast across studies was recorded for the detection bias element. A comparison of detection bias low-risk studies versus high/unclear risk studies showed no differences. The effect of sodium reduction (from 195 to 66 mmol/day) on BP in black participants was as follows: Normal blood pressure: SBP: mean difference (MD) -4.02 mmHg (95% CI:-7.37 to -0.68); DBP: MD -2.01 mmHg (95% CI:-4.37, 0.35), 253 participants, 7 trials. Hypertension: SBP: MD -6.64 mmHg (95% CI:-9.00, -4.27); DBP: MD -2.91 mmHg (95% CI:-4.52, -1.30), 398 participants, 8 trials (low-quality evidence). The effect of sodium reduction (from 217 to 103 mmol/day) on BP in Asian participants was as follows: Normal blood pressure: SBP: mean difference (MD) -1.50 mmHg (95% CI: -3.09, 0.10); DBP: MD -1.06 mmHg (95% CI:-2.53 to 0.41), 950 participants, 5 trials. Hypertension: SBP: MD -7.75 mmHg (95% CI:-11.44, -4.07); DBP: MD -2.68 mmHg (95% CI: -4.21 to -1.15), 254 participants, 8 trials (moderate-low-quality evidence).   During sodium reduction renin increased 1.56 ng/mL/hour (95%CI:1.39, 1.73) in 2904 participants (82 trials); aldosterone increased 104 pg/mL (95%CI:88.4,119.7) in 2506 participants (66 trials); noradrenalin increased 62.3 pg/mL: (95%CI: 41.9, 82.8) in 878 participants (35 trials); adrenalin increased 7.55 pg/mL (95%CI: 0.85, 14.26) in 331 participants (15 trials); cholesterol increased 5.19 mg/dL (95%CI:2.1, 8.3) in 917 participants (27 trials); triglyceride increased 7.10 mg/dL (95%CI: 3.1,11.1) in 712 participants (20 trials); LDL tended to increase 2.46 mg/dl (95%CI: -1, 5.9) in 696 participants (18 trials); HDL was unchanged -0.3 mg/dl (95%CI: -1.66,1.05) in 738 participants (20 trials) (All high-quality evidence except the evidence for adrenalin).

AUTHORS' CONCLUSIONS

In white participants, sodium reduction in accordance with the public recommendations resulted in mean arterial pressure (MAP) decrease of about 0.4 mmHg in participants with normal blood pressure and a MAP decrease of about 4 mmHg in participants with hypertension. Weak evidence indicated that these effects may be a little greater in black and Asian participants. The effects of sodium reduction on potential side effects (hormones and lipids) were more consistent than the effect on BP, especially in people with normal BP.

Salt Reduction to Prevent Hypertension and Cardiovascular Disease: JACC State-of-the-Art Review

There is strong evidence for a causal relationship between salt intake and blood pressure. Randomized trials demonstrate that salt reduction lowers blood pressure in both individuals who are hypertensive and those who are normotensive, additively to antihypertensive treatments. Methodologically robust studies with accurate salt intake assessment have shown that a lower salt intake is associated with a reduced risk of cardiovascular disease, all-cause mortality, and other conditions, such as kidney disease, stomach cancer, and osteoporosis. Multiple complex and interconnected physiological mechanisms are implicated, including fluid homeostasis, hormonal and inflammatory mechanisms, as well as more novel pathways such as the immune response and the gut microbiome. High salt intake is a top dietary risk factor. Salt reduction programs are cost-effective and should be implemented or accelerated in all countries. This review provides an update on the evidence relating salt to health, with a particular focus on blood pressure and cardiovascular disease, as well as the potential mechanisms.

Patients With Primary Aldosteronism Respond to Unilateral Adrenalectomy With Long-Term Reduction in Salt Intake

CONTEXT

High dietary salt intake is known to aggravate arterial hypertension. This effect could be of particular relevance in the setting of primary aldosteronism (PA), which is associated with cardiovascular damage independent of blood pressure levels. The aim of this study was to determine the impact of therapy on salt intake in PA patients.

PATIENTS AND METHODS

A total of 148 consecutive PA patients (66 with unilateral and 82 with bilateral PA) from the database of the German Conn's Registry were included. Salt intake was quantified by 24-hour urinary sodium excretion before and after initiation of PA treatment.

STUDY DESIGN

Observational longitudinal cohort study.

SETTING

Tertiary care hospital.

RESULTS

At baseline, unilateral PA patients had a significantly higher urinary sodium excretion than patients with bilateral disease (205 vs 178 mmol/d, P = 0.047). Higher urinary sodium excretion correlated with an increased cardiovascular risk profile including proteinuria, impaired lipid, and glucose metabolism and was associated with higher daily doses of antihypertensive drugs to achieve blood pressure control. In unilateral disease, urinary sodium excretion dropped spontaneously to 176 mmol/d (P = 0.012) 1 year after unilateral adrenalectomy and remained low at 3 years of follow-up (174 mmol/d). In contrast, treatment with mineralocorticoid receptor antagonists (MRA) in bilateral PA patients was not associated with a significant change in urinary sodium excretion at follow-up (179 mmol/d vs 183 mmol/d).

CONCLUSION

PA patients consuming a high-salt diet, estimated based on urinary sodium excretion, respond to adrenalectomy with a significant reduction of salt intake, in contrast to MRA treatment.

Is salt intake reduction a universal intervention for both normotensive and hypertensive people: a case from Iran STEPS survey 2016

PURPOSE

There is a direct association between salt intake and blood pressure (BP), one of the main risk factors for CVDs. However, yet there has been a debate that how strong is this association in people with and without hypertension. This study was conducted to evaluate the magnitude of the association between salt intake and BP in hypertensive and normotensive population among a nationally representative population.

METHODS

The study was conducted on a nationally representative sample of 18,635 Iranian adults aged 25 years and older who participated in the STEPS survey 2016 and provided urine sample. Salt intake was estimated through spot urine sample and Tanaka equation. Multiple linear regression model in survey data analysis was used to assess the independent effect of salt intake on BP.

RESULTS

After adjusting for covariates, there was a significant association between salt intake and SBP in hypertensive (p < 0.001) and normotensive people (p < 0.001). In hypertensive people, with 1 g of increase in salt intake, the SBP and DBP increased 0.37 mmHg and 0.07 mmHg, respectively. Whereas in normotensive people, with 1 g of increase in salt intake, the SBP and DBP increased 0.26 mmHg and 0.05 mmHg, respectively. Moreover, there was a significant trend toward an increase of SBP across salt intake quartiles in both hypertensive (p < 0.001) and normotensive people (p = 0.002), though the slope was steeper in hypertensive than in normotensive people.

CONCLUSIONS

The present study demonstrated that salt intake significantly increased SBP in both hypertensive and normotensive people, though the magnitude of this increase was greater in hypertensive people as compared with normotensive people.

The Salt Swap intervention to reduce salt intake in people with high blood pressure: protocol for a feasibility randomised controlled trial

BACKGROUND

High salt intake is a risk factor for hypertension and cardiovascular disease. Reducing salt intake has been shown to reduce blood pressure. Despite population-level interventions, including product reformulation and public awareness campaigns, adult salt consumption in the UK still exceeds recommendations; this is primarily due to salt consumed in processed and pre-packaged foods. Moderate or high-intensity dietary advice to encourage individuals to reduce their salt intake has been shown to be effective at reducing blood pressure, but evidence of the effectiveness of interventions that are suitable for delivery at scale in routine primary care is scarce. This feasibility trial investigates a complex behavioural change intervention to reduce dietary salt intake and blood pressure by encouraging individuals to purchase lower-salt foods when grocery shopping.

METHODS

This randomised controlled trial will test the feasibility of a novel intervention to reduce salt intake, and the trial procedures to assess its effectiveness. We will recruit participants through UK general practices and randomise 40 participants with high blood pressure, in a 2:1 allocation to receive either the Salt Swap intervention or a control information leaflet. The primary outcomes relate to the criteria for progression to a large-scale trial. These include follow-up rates at 6 weeks, fidelity of intervention delivery and use of the intervention mobile app. Secondary outcomes include the effect of the intervention on the salt content of purchased foods (grams per 100 g), urinary sodium excretion assessed through 24-hour urine samples and blood pressure. Trial process measures will be collected and qualitative assessment will provide insights into participant engagement with the intervention content and perceived barriers to and facilitators of salt reduction dietary behavioural change.

DISCUSSION

If the outcomes indicate the trial is feasible and there is evidence that behavioural change may result in salt reduction, we will proceed to a definitive trial to test the effectiveness of the intervention to lower blood pressure. If successful, this intervention approach could be applied not only to people with high blood pressure, but also to the wider population with normal blood pressure in whom dietary salt intake exceeds recommendations.

TRIAL REGISTRATION

ISRCTN, 20910962 . Registered on 5 April 2017.

Production of Fermented Kale Juices with Lactobacillus Strains and Nutritional Composition

Fermented kale juices using four types of lactobacilli were produced in the present study. After 48 h of fermentation time, viable cell counts of all ferments reached an above 10⁹ CFU/mL. The viability of the ferments after cold storage in the refrigerator for 4 weeks showed 10⁸ CFU/mL in all ferments. Among four types of fermented kale juices, the ferment of Lactobacillus acidophilus IFO 3025 indicated a good nutritional composition, including neutral sugar (1,909.76 μg/mL), reducing sugar (564.00 μg/mL, P<0.05), and protein contents (160.06 μg/mL, P<0.05). The results of mineral composition analysis had the highest potassium value in all ferments (854.16~895.07 μg/mL), particularly in the ferment of Lactobacillus brevis FSB-1 (P<0.001), which is necessary to sustain osmotic pressure, prevention of high blood pressure, and protein synthesis. Moreover, calcium, phosphorus, and magnesium contents related to bone health were generally sufficient in all ferments. Consequently, in this study, fermented kale juices may be suggested as a healthy fermented beverage with essential nutrients. However, the acceptability of the fermented kale juice to the Korean taste should be further investigated with a trained taste panel to determine whether inoculated fermentation could be an option for the consumers.

Systematic review of dietary salt reduction policies: Evidence for an effectiveness hierarchy?

BACKGROUND

Non-communicable disease (NCD) prevention strategies now prioritise four major risk factors: food, tobacco, alcohol and physical activity. Dietary salt intake remains much higher than recommended, increasing blood pressure, cardiovascular disease and stomach cancer. Substantial reductions in salt intake are therefore urgently needed. However, the debate continues about the most effective approaches. To inform future prevention programmes, we systematically reviewed the evidence on the effectiveness of possible salt reduction interventions. We further compared "downstream, agentic" approaches targeting individuals with "upstream, structural" policy-based population strategies.

METHODS

We searched six electronic databases (CDSR, CRD, MEDLINE, SCI, SCOPUS and the Campbell Library) using a pre-piloted search strategy focussing on the effectiveness of population interventions to reduce salt intake. Retrieved papers were independently screened, appraised and graded for quality by two researchers. To facilitate comparisons between the interventions, the extracted data were categorised using nine stages along the agentic/structural continuum, from "downstream": dietary counselling (for individuals, worksites or communities), through media campaigns, nutrition labelling, voluntary and mandatory reformulation, to the most "upstream" regulatory and fiscal interventions, and comprehensive strategies involving multiple components.

RESULTS

After screening 2,526 candidate papers, 70 were included in this systematic review (49 empirical studies and 21 modelling studies). Some papers described several interventions. Quality was variable. Multi-component strategies involving both upstream and downstream interventions, generally achieved the biggest reductions in salt consumption across an entire population, most notably 4g/day in Finland and Japan, 3g/day in Turkey and 1.3g/day recently in the UK. Mandatory reformulation alone could achieve a reduction of approximately 1.45g/day (three separate studies), followed by voluntary reformulation (-0.8g/day), school interventions (-0.7g/day), short term dietary advice (-0.6g/day) and nutrition labelling (-0.4g/day), but each with a wide range. Tax and community based counselling could, each typically reduce salt intake by 0.3g/day, whilst even smaller population benefits were derived from health education media campaigns (-0.1g/day). Worksite interventions achieved an increase in intake (+0.5g/day), however, with a very wide range. Long term dietary advice could achieve a -2g/day reduction under optimal research trial conditions; however, smaller reductions might be anticipated in unselected individuals.

CONCLUSIONS

Comprehensive strategies involving multiple components (reformulation, food labelling and media campaigns) and "upstream" population-wide policies such as mandatory reformulation generally appear to achieve larger reductions in population-wide salt consumption than "downstream", individually focussed interventions. This 'effectiveness hierarchy' might deserve greater emphasis in future NCD prevention strategies.

Relationship between urinary sodium with blood pressure and hypertension among a Kazakh community population in Xinjiang, China

Urinary sodium levels are reported to be associated with blood pressure in clinical trials and epidemiology studies. Nevertheless, the public health message of reducing sodium intake in free-living community populations remains under debate. Based on an ongoing prospective study initiated in 2012 with a community-based design in Xinjiang, China, 1668 adults (⩾30 years old) were assessed in the current study for associations between urinary sodium and blood pressure and hypertension in a free-living population of Kazakh people. After excluding 223 people on antihypertensive medication, 1445 participants were analyzed. Second urine samples after waking were used to estimate 24-h urinary sodium excretion, which is a marker for sodium intake. Following analyses, we found that the distribution of systolic and diastolic blood pressures moved upward with increasing quartiles of urinary sodium. After adjusting for age, differences in median systolic blood pressure were 8.5 mm Hg for men and 8.0 mm Hg for women between the top and bottom urinary sodium quartiles, and differences for diastolic blood pressure were 4.7 mm Hg for men and 4.3 mm Hg for women. A significant increased risk for hypertension was observed for the top quartile of urinary sodium after adjusting for age, body mass index, smoking, alcohol consumption, fruit and vegetable consumption, with corresponding odds ratios being 1.61 (95% confidence interval (CI): 1.02-2.54) for men and 1.92 (95% CI: 1.13-3.27) for women. Improving education about reducing salt intake is of particular public importance to reduce blood pressure and the risk for hypertension among the Kazakh people.

Effects of low sodium diet versus high sodium diet on blood pressure, renin, aldosterone, catecholamines, cholesterol, and triglyceride

BACKGROUND

In spite of more than 100 years of investigations the question of whether a reduced sodium intake improves health is still unsolved.

OBJECTIVES

To estimate the effects of low sodium intake versus high sodium intake on systolic and diastolic blood pressure (SBP and DBP), plasma or serum levels of renin, aldosterone, catecholamines, cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and triglycerides.

SEARCH METHODS

The Cochrane Hypertension Information Specialist searched the following databases for randomized controlled trials up to March 2016: the Cochrane Hypertension Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (2016, Issue 3), MEDLINE (from 1946), Embase (from 1974), the World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.gov. We also searched the reference lists of relevant articles.

SELECTION CRITERIA

Studies randomising persons to low-sodium and high-sodium diets were included if they evaluated at least one of the above outcome parameters.

DATA COLLECTION AND ANALYSIS

Two review authors independently collected data, which were analysed with Review Manager 5.3.

MAIN RESULTS

A total of 185 studies were included. The average sodium intake was reduced from 201 mmol/day (corresponding to high usual level) to 66 mmol/day (corresponding to the recommended level).The effect of sodium reduction on blood pressure (BP) was as follows: white people with normotension: SBP: mean difference (MD) -1.09 mmHg (95% confidence interval (CI): -1.63 to -0.56; P = 0.0001); 89 studies, 8569 participants; DBP: + 0.03 mmHg (MD 95% CI: -0.37 to 0.43; P = 0.89); 90 studies, 8833 participants. High-quality evidence. Black people with normotension: SBP: MD -4.02 mmHg (95% CI:-7.37 to -0.68; P = 0.002); seven studies, 506 participants; DBP: MD -2.01 mmHg (95% CI:-4.37 to 0.35; P = 0.09); seven studies, 506 participants. Moderate-quality evidence. Asian people with normotension: SBP: MD -0.72 mmHg (95% CI: -3.86 to 2.41; P = 0.65); DBP: MD -1.63 mmHg (95% CI:-3.35 to 0.08; P =0.06); three studies, 393 participants. Moderate-quality evidence.White people with hypertension: SBP: MD -5.51 mmHg (95% CI: -6.45 to -4.57; P < 0.00001); 84 studies, 5925 participants; DBP: MD -2.88 mmHg (95% CI: -3.44 to -2.32; P < 0.00001); 85 studies, 6001 participants. High-quality evidence. Black people with hypertension: SBP MD -6.64 mmHg (95% CI:-9.00 to -4.27; P = 0.00001); eight studies, 619 participants; DBP -2.91 mmHg (95% CI:-4.52, -1.30; P = 0.0004); eight studies, 619 participants. Moderate-quality evidence. Asian people with hypertension: SBP: MD -7.75 mmHg (95% CI:-11,44 to -4.07; P < 0.0001) nine studies, 501 participants; DBP: MD -2.68 mmHg (95% CI: -4.21 to -1.15; P = 0.0006). Moderate-quality evidence.In plasma or serum, there was a significant increase in renin (P < 0.00001), aldosterone (P < 0.00001), noradrenaline (P < 0.00001), adrenaline (P < 0.03), cholesterol (P < 0.0005) and triglyceride (P < 0.0006) with low sodium intake as compared with high sodium intake. All effects were stable in 125 study populations with a sodium intake below 250 mmol/day and a sodium reduction intervention of at least one week.

AUTHORS' CONCLUSIONS

Sodium reduction from an average high usual sodium intake level (201 mmol/day) to an average level of 66 mmol/day, which is below the recommended upper level of 100 mmol/day (5.8 g salt), resulted in a decrease in SBP/DBP of 1/0 mmHg in white participants with normotension and a decrease in SBP/DBP of 5.5/2.9 mmHg in white participants with hypertension. A few studies showed that these effects in black and Asian populations were greater. The effects on hormones and lipids were similar in people with normotension and hypertension. Renin increased 1.60 ng/mL/hour (55%); aldosterone increased 97.81 pg/mL (127%); adrenalin increased 7.55 pg/mL (14%); noradrenalin increased 63.56 pg/mL: (27%); cholesterol increased 5.59 mg/dL (2.9%); triglyceride increased 7.04 mg/dL (6.3%).

Health Promotion and Preventive Care Intervention for Older Community-Dwelling People: Long-Term Effects of a Randomised Controlled Trial (RCT) within the LUCAS Cohort

OBJECTIVES

An RCT of a health promotion and preventive care intervention was done in 2001-2002. Here, long-term analyses based on 12 years of follow-up of survival and of change in functional competence between intervention and control group are presented. Positive 1-year results (significantly higher use of preventive services and better health behaviour) were presented earlier.

DESIGN

Parallel group randomised controlled trial (RCT) with 878 participants in the intervention and 1,702 participants in the control group.

SETTING

The study took place in Hamburg, Germany and made use of health care structures and professionals of a geriatrics centre.

PARTICIPANTS

Study participants were initially community-dwelling, aged 60 years and older and without B-ADL-restrictions, cognitive impairment, or need of nursing care, with sufficient command of the German language.

INTERVENTIONS

Health promotion and preventive care interventions relied on an extensive health questionnaire and the subsequent offer to participate in multi-topic personal reinforcement performed in small group sessions or at preventive home visits.

MEASUREMENTS

Primary outcome: Survival time; in some analyses, adjustments were made for gender, age and self-perceived health. Secondary outcome: Functional competence (LUCAS Functional Ability Index) based on responses to self-administered questionnaires at 1-year follow-up and 12 years after 1-year follow-up (2013/2014).

RESULTS

Mean time under observation was 10.3 years. 38.3% (987/2,580) of the participants died; intervention group (IG): 35.7% (313/878), control group (CG): 39.6% (674/1,702); HR=0.89; p=0.09. Functional competence at 1-year follow-up: IG: ROBUST 67.4% (391/580), FRAIL 11.9% (69/580) vs. CG: ROBUST 62.9% (861/1,368), FRAIL 14.8% (203/1,368); p=0.12. 12-years after 1-year follow-up: IG: ROBUST 50.0% (160/320), FRAIL 30.9% (99/320) vs. CG: ROBUST 48.9% (307/628), FRAIL 34.1% (214/628); p=0.56.

CONCLUSIONS

Insignificant but consistent effects on survival and the dynamics of functional competence suggest effectivity of the complex intervention. We plan to take a closer look at the effect of each reinforcement separately.

The Impact of Nursing Interventions

The purpose of this article is to present findings from a review of published systematic/integrative reviews and meta-analyses on nursing interventions and patient outcomes in acute care settings. A literature search was conducted for the period 1999-2005, producing 4,000 systematic/integrative reviews and 500 meta-analyses covering seven topics selected by the authors: elder care, caregivers, developmental care of neonates and infants, symptom management, pressure ulcer prevention/treatment, incontinence, and staffing. The association between nursing care interventions/processes and patient outcomes in acute care settings was found to be limited in the articles reviewed. The strongest evidence was for the use of patient risk-assessment tools and interventions implemented by nurses to prevent patient harm. We observed significant variation in methods to measure the effect of independent variables (nursing interventions) on patient outcomes. Results indicate the need for more research measuring the effect of specific nursing interventions that may impact acute care patient outcomes.

State of the Art Reviews: Relationship Between Diet/ Physical Activity and Health

Obesity and 4 of the leading causes of death—heart disease, cancer, stroke, and type 2 diabetes mellitus—are related to lifestyle. The combination of a healthy weight, prudent diet, and daily physical activity clearly plays a role in primary, secondary, and tertiary prevention of these and other chronic diseases. Because nearly 65% of the adult population is overweight or obese, weight loss and maintenance are central to this review article. Improved lipid profiles, blood pressure, insulin sensitivity, and euglycemia are associated with weight loss or a normal body weight; thus, maintaining a healthy weight is a universal recommendation for health. The methods for improving lifestyle described in the section on obesity include assessing nutritional status and stages of change of the client, setting realistic goals, eating a diet high in fruits and vegetables with low-fat sources of dairy and protein, and achieving appropriate physical activity levels. The importance of physicians discussing weight with clients and vice versa is stressed. The common features of lifestyle-related diseases make them amenable to similar lifestyle interventions.

Comparison of sodium content of meals served by independent takeaways using standard versus reduced holed salt shakers: cross-sectional study

Background

Takeaway food has a relatively poor nutritional profile. Providing takeaway outlets with reduced-holed salt shakers is one method thought to reduce salt use in takeaways, but effects have not been formally tested. We aimed to determine if there was a difference in sodium content of standard fish and chip meals served by Fish & Chip Shops that use standard (17 holes) versus reduced-holed (5 holes) salt shakers, taking advantage of natural variations in salt shakers used.

Methods

We conducted a cross-sectional study of all Fish & Chip Shops in two local government areas (n = 65), where servers added salt to meals as standard practice, and salt shaker used could be identified (n = 61). Standard fish and chip meals were purchased from each shop by incognito researchers and the purchase price and type of salt shaker used noted. Sodium content of full meals and their component parts (fish, chips, and fish batter) was determined using flame photometry. Differences in absolute and relative sodium content of meals and component parts between shops using reduced-holed versus standard salt-shakers were compared using linear regression before and after adjustment for purchase price and area.

Results

Reduced-holed salt shakers were used in 29 of 61 (47.5 %) included shops. There was no difference in absolute sodium content of meals purchased from shops using standard versus reduced-holed shakers (mean = 1147 mg [equivalent to 2.9 g salt]; SD = 424 mg; p > 0.05). Relative sodium content was significantly lower in meals from shops using reduced-holed (mean = 142.5 mg/100 g [equivalent to 0.4 g salt/100 g]; SD = 39.0 mg/100 g) versus standard shakers (mean = 182.0 mg/100 g; [equivalent to 0.5 g salt/100 g]; SD = 68.3 mg/100 g; p = 0.008). This was driven by differences in the sodium content of chips and was extinguished by adjustment for purchase price and area. Price was inversely associated with relative sodium content (p < 0.05).

Conclusions

Using reduced-holed salt shakers in Fish & Chip Shops is associated with lower relative sodium content of fish and chip meals. This is driven by differences in sodium content of chips, making our results relevant to the wide range of takeaways serving chips. Shops serving higher priced meals, which may reflect a more affluent customer base, may be more likely to use reduced-holed shakers.

Sodium and potassium intake in South Africa: an evaluation of 24-hour urine collections in a white, black, and Indian population

Limited number of studies on salt intake has been conducted in the South Africa. The present study established the sodium and potassium excretion (24-hour urine collection) of three different South African populations. In total, 692 successful 24-hour urine collections were analyzed for sodium, potassium, and iodine levels. The median sodium and potassium excretion was 122.9 and 33.5 mmol/d, respectively, and the median salt intake was 7.2 g/d. The majority (92.8%) of the population did not meet the recommended potassium intake/d, and 65.6% consumed more than 6 g of salt/d. Potassium excretion showed a linear relationship with salt intake (P-trend ≤ .001). The median sodium-to-potassium ratio was 3.5. These findings support the South African government's sodium reduction legislation, as well as global initiatives. More consideration should be given to promoting the intake of potassium-rich foods, as this may have a greater public health impact than focusing only on dietary sodium reduction.

Nutrition and Cardiovascular Disease: Finding the Perfect Recipe for Cardiovascular Health

The increasing burden of cardiovascular disease (CVD) despite the progress in management entails the need of more effective preventive and curative strategies. As dietary-associated risk is the most important behavioral factor influencing global health, it appears the best target in the challenge against CVD. Although for many years, since the formulation of the cholesterol hypothesis, a nutrient-based approach was attempted for CVD prevention and treatment, in recent years a dietary-based approach resulted more effective in reducing cardiovascular risk worldwide. After the publication of randomized trials on the remarkable effects of the Mediterranean diet and the Dietary Approach to Stop Hypertension (DASH) diet on CVD, new efforts were put on research about the effects of complex dietary interventions on CVD. The purpose of this paper is to review the evidence on dietary interventions in the prevention and disease modification of CVD, focusing on coronary artery disease and heart failure, the main disease responsible for the enormous toll taken by CVD worldwide.

State-level and community-level salt reduction initiatives: a systematic review of global programmes and their impact

BACKGROUND

High-salt diets are linked to elevated blood pressure, a major risk factor for cardiovascular diseases, particularly stroke. State and community salt reduction strategies may complement nationally led initiatives and contribute to achieving global salt reduction targets. We aim to systematically review such interventions and document reported impact where programmes have been evaluated.

METHODS

Electronic databases were searched up to June 2015 using terms 'salt' or 'sodium' and 'state' and 'community' in combination with 'campaign', 'initiative', 'project', 'strategy', 'intervention' or 'programme'. Data from evaluated and unevaluated interventions were included. Studies were analysed in relation to intervention components and outcome measures and appraised for quality using a Cochrane Risk-of-Bias Tool.

RESULTS

39 state and community programmes were identified. Settings varied from whole communities (n=23), state-owned buildings (n=5), schools (n=7), workplaces (n=3) and correctional facilities (n=1). Strategies included nutrition education programmes, public education campaigns, changes to the food environment, other 'novel' approaches and multifaceted approaches. Of the 28 studies that evaluated intervention effectiveness, significant reductions were observed in terms of salt intake from dietary assessment (n=7), urinary sodium excretion (n=8), blood pressure (n=11) and sodium in foods (n=9). Six studies reported positive changes in consumer knowledge, attitudes and behaviours. All but two studies had some methodological limitations.

CONCLUSIONS

State and community salt reduction programmes may be effective in a range of settings but more robust evaluation methods are needed. Scaling up these efforts in coordination with national initiatives could provide the most effective and sustainable approach to reducing population salt intake.

Identification of dietary patterns associated with blood pressure in a sample of overweight Australian adults

The dietary approaches to stop hypertension (DASH) diet provides strong evidence for an optimal dietary pattern for blood pressure (BP) control; however, investigation at the level of key foods in a dietary pattern is sparse. This study aimed to assess the relationship between dietary patterns driven by key foods with BP in a sample of obese Australian adults. Secondary analysis was conducted on baseline data of 118 participants (45.1±8.4 years, mean BP=124.1±15.8/72.6±9.2 mm Hg) recruited in a weight reduction randomized controlled trial (ACTRN12608000425392). Dietary assessment was by a validated diet history interview. The average of three office BP measurements was taken. Factor analysis extracted dietary patterns and their relation to systolic BP (SBP) and diastolic BP (DBP) was analysed using multiple linear regression. Eight dietary patterns were identified based on leading foods: meat and alcohol; seafood; fats; fruits and nuts; legumes; confectionery; sweet foods; and yeast extracts and seasonings. A lower SBP was associated with alignment with the fruit and nuts pattern (β=-4.1 (95% confidence interval -7.5 to -0.7) mm Hg) and with seafood for DBP (β=-2.4 (-4.6 to -0.3) mm Hg). SBP and DBP were higher with yeast extract and seasonings (β=4.3 (1.4-7.3); 2.5 (0.9-4.0) mm Hg, respectively). In obese adults attending for weight loss, dietary patterns that included larger amounts of fruits and nuts and/or seafood were associated with lower BP at baseline, whereas patterns that were characterised by yeast extract and seasonings were associated with higher BP.

A randomized controlled trial of co-payment elimination: the CHORD trial

OBJECTIVES

Efforts to improve adherence by reducing co-payments through value-based insurance design are become more prevalent despite limited evidence of improved health outcomes. The objective of this study was to determine whether eliminating patient co-payments for blood pressure medications improves blood pressure control.

STUDY DESIGN

Randomized controlled trial.

METHODS

The Collaboration to Reduce Disparities in Hypertension (CHORD) was a randomized controlled trial with 12 months' follow-up conducted among patients from the Philadelphia and Pittsburgh Veterans Administration Medical Centers. We enrolled 479 patients with poorly controlled systolic blood pressure. Participants were randomly assigned to: a) receive reductions in co-payments from $8 to $0 per medication per month for each antihypertensive prescription filled, b) a computerized behavioral intervention (CBI), c) both co-pay reduction and CBI, or d) usual care. Our main outcome measure was change in systolic blood pressure from enrollment to 12 months post enrollment. We also measured adherence using the medication possession ratio in a subset of participants.

RESULTS

There were no significant interactions between the co-payment interventions and the CBI interventions. There was no relative difference in the change in medication possession ratio between baseline and 12 months (0.05% and -.90% in control and incentive groups, respectively; P = .74) or in continuous medication gaps of 30, 60, or 90 days. Blood pressure decreased among all participants, but to a similar degree between the financial incentive and control groups. Systolic pressure within the incentive group dropped 13.2 mm Hg versus 15.2 mm Hg for the control group (difference = 2.0; 95% CI, -2.3 to 6.3; P = .36). The proportion of patients with blood pressure under control at 12 months was 29.5% in the incentive group versus 33.9 in the control group (odds ratio, 0.8; 95% CI, 0.5-1.3; P = .36).

CONCLUSIONS

Among patients with poorly controlled blood pressure, financial incentives--as implemented in this trial--that reduced patient cost sharing for blood pressure medications did not improve medication adherence or blood pressure control.

A randomized controlled trial of negative co-payments: the CHORD trial

OBJECTIVES

Value-based insurance designs are being widely used. We undertook this study to examine whether a financial incentive that lowered co-payments for blood pressure medications below $0 improved blood pressure control among patients with poorly controlled hypertension.

STUDY DESIGN

Randomized controlled trial.

METHODS

Participants from 3 Pennsylvania hospitals (n = 337) were randomly assigned to: a) be paid $8 per medication per month for filling blood pressure prescriptions, b) a computerized behavioral intervention (CBI), c) both payment and CBI, or d) usual care. The primary outcome was change in blood pressure between baseline and 12 months post enrollment. We also measured adherence using the medication possession ratio in a subset of participants.

RESULTS

There were no significant interactions between the incentive and the CBI interventions. There were no significant changes in medication possession ratio in the treatment group. Blood pressure decreased among all participants, but to a similar degree between the financial incentive and control groups. Systolic blood pressure (SBP) dropped 13.7 mm Hg for the incentive group versus 10.0 mm Hg for the control group (difference = –3.7; 95% CI, –9.0 to 1.6; P = .17). The proportion of patients with blood pressure under control 12 months post enrollment was 35.6% of the incentive group versus 27.7% of the control group (odds ratio, 1.4; 95% CI, 0.8-2.5; P = .19). Diabetics in the incentive group had an average drop in SBP of 12.7 mm Hg between baseline and 12 months compared with 4.0 mm Hg in the control group (P = .02). Patients in the incentive group without diabetes experienced average SBP reductions of 15.0 mm Hg, compared with 16.3 mm Hg for control group nondiabetics (P = .71).

CONCLUSIONS

Among patients with poorly controlled blood pressure, financial incentives—as implemented in this trial—did not improve blood pressure control or adherence except among patients with diabetes.

Prevention and control of hypertension: developing a global agenda

PURPOSE OF REVIEW

This review demonstrates the need for enhancing strategic approaches to the prevention and control of hypertension, a global health issue.

RECENT FINDINGS

An epidemic of chronic noncommunicable diseases is threatening national healthcare systems' sustainability and the economy of many countries. Increased blood pressure is the leading risk for premature death and disability and accounts for approximately 10% of healthcare spending. Four of nine recent United Nations' targets for reducing chronic noncommunicable diseases relate directly or indirectly to hypertension. The expanded chronic care model provides a comprehensive framework for developing hypertension prevention and control strategies. The model addresses the roles of healthy public policy, healthy living environments, healthy communities, reorientation of health services delivery toward management of chronic illness, support for improving clinical decisions, enhanced skills of people to prevent and self-manage chronic disease, partnerships of stakeholders and information systems to track the impact of interventions and identify care 'gaps'. The authors advocate that hypertension organizations can lead aspects of hypertension strategy development and implementation.

SUMMARY

Prevention and control of hypertension requires a strategic approach that could have a central role for hypertension experts and the hypertension community.

Altered dietary salt intake for people with chronic kidney disease

BACKGROUND

Salt intake shows great promise as a modifiable risk factor for reducing heart disease incidence and delaying kidney function decline in people with chronic kidney disease (CKD). However, a clear consensus of the benefits of reducing salt in people with CKD is lacking.

OBJECTIVES

This review evaluated the benefits and harms of altering dietary salt intake in people with CKD.

SEARCH METHODS

We searched the Cochrane Renal Group's Specialised Register to 13 January 2015 through contact with the Trials' Search Co-ordinator using search terms relevant to this review.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared two or more levels of salt intake in people with any stage of CKD.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for eligibility and conducted risk of bias evaluation. Results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes, and mean difference (MD) and 95% CI for continuous outcomes. Mean effect sizes were calculated using the random-effects models.

MAIN RESULTS

We included eight studies (24 reports, 258 participants). Because duration of the included studies was too short (1 to 26 weeks) to test the effect of salt restriction on endpoints such as mortality, cardiovascular events or CKD progression, changes in salt intake on blood pressure and other secondary risk factors were applied. Three studies were parallel RCTs and five were cross-over studies. Selection bias was low in five studies and unclear in three. Performance and detection biases were low in two studies and unclear in six. Attrition and reporting biases were low in four studies and unclear in four. One study had the potential for high carryover effect; three had high risk of bias from baseline characteristics (change of medication or diet) and two studies were industry funded.There was a significant reduction in 24 hour sodium excretion associated with low salt interventions (range 52 to 141 mmol) (8 studies, 258 participants: MD -105.86 mmol/d, 95% CI -119.20 to -92.51; I(2) = 51%). Reducing salt intake significantly reduced systolic blood pressure (8 studies, 258 participants: MD -8.75 mm Hg, 95% CI -11.33 to -6.16; I(2) = 0%) and diastolic blood pressure (8 studies, 258 participants: MD -3.70 mm Hg, 95% CI -5.09 to -2.30; I(2) = 0%). One study reported restricting salt intake reduced the risk of oedema by 56%. Salt restriction significantly increased plasma renin activity (2 studies, 71 participants: MD 1.08 ng/mL/h, 95% CI 0.51 to 1.65; I(2) = 0%) and serum aldosterone (2 studies, 71 participants: 6.20 ng/dL (95% CI 3.82 to 8.58; I(2) = 0%). Antihypertensive medication dosage was significantly reduced with a low salt diet (2 studies, 52 participants): RR 5.48, 95% CI 1.27 to 23.66; I(2) = 0%). There was no significant difference in eGFR (2 studies, 68 participants: MD -1.14 mL/min/1.73 m(2), 95% CI -4.38 to 2.11; I(2) = 0%), creatinine clearance (3 studies, 85 participants): MD -4.60 mL/min, 95% CI -11.78 to 2.57; I(2) = 0%), serum creatinine (5 studies, 151 participants: MD 5.14 µmol/L, 95% CI -8.98 to 19.26; I(2) = 59%) or body weight (5 studies, 139 participants: MD -1.46 kg; 95% CI -4.55 to 1.64; I(2) = 0%). There was no significant change in total cholesterol in relation to salt restriction (3 studies, 105 participants: MD -0.23 mmol/L, 95% CI -0.57 to 0.10; I(2) = 0%) or symptomatic hypotension (2 studies, 72 participants: RR 6.60, 95% CI 0.77 to 56.55; I(2) = 0%). Salt restriction significantly reduced urinary protein excretion in all studies that reported proteinuria as an outcome, however data could not be meta-analysed.

AUTHORS' CONCLUSIONS

We found a critical evidence gap in long-term effects of salt restriction in people with CKD that meant we were unable to determine the direct effects of sodium restriction on primary endpoints such as mortality and progression to end-stage kidney disease (ESKD). We found that salt reduction in people with CKD reduced blood pressure considerably and consistently reduced proteinuria. If such reductions could be maintained long-term, this effect may translate to clinically significant reductions in ESKD incidence and cardiovascular events. Research into the long-term effects of sodium-restricted diet for people with CKD is warranted, as is investigation into adherence to a low salt diet.

Sodium intake in US ethnic subgroups and potential impact of a new sodium reduction technology: NHANES Dietary Modeling

BACKGROUND

Because excessive dietary sodium intake is a major contributor to hypertension, a reduction in dietary sodium has been recommended for the US population. Using the National Health and Nutrition Examination Survey (NHANES) 2007-2010 data, we estimated current sodium intake in US population ethnic subgroups and modeled the potential impact of a new sodium reduction technology on sodium intake.

METHODS

NHANES 2007-2010 data were analyzed using The National Cancer Institute method to estimate usual intake in population subgroups. Potential impact of SODA-LO® Salt Microspheres sodium reduction technology on sodium intake was modeled using suggested sodium reductions of 20-30% in 953 foods and assuming various market penetrations. SAS 9.2, SUDAAN 11, and NHANES survey weights were used in all calculations with assessment across age, gender and ethnic groups.

RESULTS

Current sodium intake across all population subgroups exceeds the Dietary Guidelines 2010 recommendations and has not changed during the last decade. However, sodium intake measured as a function of food intake has decreased significantly during the last decade for all ethnicities. "Grain Products" and "Meat, Poultry, Fish, & Mixtures" contribute about 2/3rd of total sodium intake. Sodium reduction, using SODA-LO® Salt Microspheres sodium reduction technology (with 100% market penetration) was estimated to be 185-323 mg/day or 6.3-8.4% of intake depending upon age, gender and ethnic group.

CONCLUSIONS

Current sodium intake in US ethnic subgroups exceeds the recommendations and sodium reduction technologies could potentially help reduce dietary sodium intake among those groups.

Stroke Prevention and Sodium Restriction

Stroke prevention is extremely cost-effective. The Ontario Task Force for the Coordinated Stroke Strategy for Ontario received from Dr. Muhammad Mamdani of the Institute for Clinical Evaluative Sciences the estimate that stroke prevention is approximately ten times more cost-effective than treating acute stroke with tPA.1 Hackam and Spence2 have calculated that in the highest-risk patients it would be possible to reduce the risk of stroke by more than 90% by a combination of interventions (including blood pressure control, smoking cessation, diet, treatment of diabetes, lipid-lowering therapy, and for patients in whom it is indicated, anticoagulation for atrial fibrillation or carotid endarterectomy). Dr Mukul Sharma (personal communication) has shown that stroke prevention is a dominant strategy in health economic terms; i.e. that it improves outcomes while reducing net costs. Effective control of hypertension has the potential to reduce stroke by half.3,4 Because hypertension is so prevalent, it accounts for the greatest population attributable risk for stroke, and thus represents the greatest opportunity to reduce stroke.

Proposed nomenclature for salt intake and for reductions in dietary salt

There is considerable confusion about what ranges of dietary salt(a) could be considered low, normal, or high and also what ranges of reduction in dietary salt are small or large. The World Hypertension League with other organizations involved in dietary salt reduction have proposed a standardized nomenclature based on normal ancestral levels of salt intake and also on ranges of reduction in salt intake in clinical and population interventions. Low daily salt (sodium) intake where harm due to deficiency would be expected to occur is recommended to remain undefined because of inadequate research but likely <0.25 g (100 mg), normal (physiological) intake <2.5 g (1000 mg), recommended intake <5.0 g (2000 mg), high ≥5.0 g (2000 mg), very high >10 to 15 g (4000-6000 mg), and extremely high >15 g (6000 mg). Reductions in daily salt (sodium) intake are recommended to be called small if <2.5 g (1000 mg), moderate if 2.5 to 5.0 g (1000-2000 mg) and large if >5.0 g (2000 mg). Use of this nomenclature is likely to result in less confusion about salt intake and interventions to reduce dietary sodium.

Amiloride-sensitive sodium currents in fungiform taste cells of rats chronically exposed to nicotine

Many studies have demonstrated that chronic exposure to nicotine, one of the main components of tobacco smoke, has profound effects on the functionality of the mammalian taste system. However, the mechanisms underlying nicotine action are poorly understood. In particular no information is available on the chronic effect of nicotine on the functioning of taste cells, the peripheral detectors which transduce food chemicals into electrical signals to the brain. To address this issue, I studied the membrane properties of rat fungiform taste cells and evaluated the effect of long-term exposure to nicotine on the amiloride-sensitive sodium currents (ASSCs). These currents are mediated by the epithelial sodium channels (ENaC) thought to be important, at least in part, in the transduction of salty stimuli. Patch-clamp recording data indicated that ASSCs in taste cells from rats chronically treated with nicotine had a reduced amplitude compared to controls. The pharmacological and biophysical analysis of ASSCs revealed that amplitude reduction was not dependent on changes in amiloride sensitivity or channel ionic permeability, but likely derived from a decrease in the activity of ENaCs. Since these channels are considered to be sodium receptors in taste cells, my results suggest that chronic exposure to nicotine hampers the capability of these cells to respond to sodium ions. This might represent a possible cellular mechanism underlying the reduced taste sensitivity to salt typically found in smokers.

To legislate or not to legislate? A comparison of the UK and South African approaches to the development and implementation of salt reduction programs

The World Health Organization promotes salt reduction as a best-buy strategy to reduce chronic diseases, and Member States have agreed to a 30% reduction target in mean population salt intake by 2025. Whilst the UK has made the most progress on salt reduction, South Africa was the first country to pass legislation for salt levels in a range of processed foods. This paper compares the process of developing salt reduction strategies in both countries and highlights lessons for other countries. Like the UK, the benefits of salt reduction were being debated in South Africa long before it became a policy priority. Whilst salt reduction was gaining a higher profile internationally, undoubtedly, local research to produce context-specific, domestic costs and outcome indicators for South Africa was crucial in influencing the decision to legislate. In the UK, strong government leadership and extensive advocacy activities initiated in the early 2000s have helped drive the voluntary uptake of salt targets by the food industry. It is too early to say which strategy will be most effective regarding reductions in population-level blood pressure. Robust monitoring and transparent mechanisms for holding the industry accountable will be key to continued progress in each of the countries.