Fortnightly review: Beneficial effects of potassium

Association between ischemic heart disease and dietary intake of lycopene: a case-control study

Aim

The effect of dietary lycopene on ischemic heart disease (IHD) is not clear. Hence, this study aimed to determine the association between dietary lycopene and IHD.

Methods

This case-control study was conducted on 443 patients with physician confirmed diagnosis of IHD as the case group and 443 healthy individuals as the control group. Data on demographic, medical history, anthropometric, and physical activity of the participants were collected. Food intake was evaluated using a 237-item semi-quantitative food frequency questionnaire (FFQ). The dietary intake of lycopene was assessed using Nutritionist IV software.

Results

A negative association was found between IHD and lycopene (OR: 0.98, CI 95%: 0.963-0.996, p = 0.02). The results remained significant after adjustment for age and sex, additional adjustment for dietary intake of calorie and fat, further adjustments for BMI, and additional adjustment for smoking, drinking alcohol, and physical activity. The risk of IHD in people with the highest quartile of dietary intake of lycopene was significantly lower than those with the lowest quartile (OR = 0.67, CI 95%: 0.46-0.97, p = 0.036).

Conclusion

There was a significant inverse relationship between intake of lycopene and IHD. Further prospective studies in different populations are required to elucidate the roles of lycopene against IHD.

Urinary Na/K ratio is a predictor of developing chronic kidney disease in the general population

Chronic kidney disease (CKD) is a major risk factor for cardiovascular diseases as well as end-stage kidney disease. Increased dietary sodium (Na) or decreased dietary potassium (K) deteriorates kidney function; however, findings regarding the association of dietary Na/K ratio with kidney function are limited and conflicting. Therefore, the present study investigated the impact of urinary Na/K ratio on the development of CKD, defined as estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2, in the Japanese general population. In total, 14,549 subjects without CKD who participated in our medical checkup were enrolled. The urinary Na/K ratio was measured using a sample of overnight urine. The subjects were followed up until the endpoint (onset of CKD). During the median follow-up period of 61.4 months, CKD developed in 2096 participants (25.9 per 1000 person-years). The risk of developing CKD increased across the quartiles of baseline urinary Na/K ratio in the Kaplan-Meier analysis (log-rank, P < 0.001). In multivariate Cox proportional hazard regression analysis, urinary Na/K ratio was a significant predictor of new-onset CKD after adjustment for important factors including eGFR at baseline (hazard ratio, 2.013; 95% confidence interval, 1.658-2.445; p < 0.001). Moreover, baseline urinary Na/K ratio was found to be independently correlated with yearly decline in eGFR. Similar results were obtained in subgroups of participants with and without hypertension. Thus, urinary Na/K ratio is significantly associated with the development of CKD in the general population.

Fruit and vegetable consumption and the risk of hypertension: a systematic review and meta-analysis of prospective studies

PURPOSE

A high fruit and vegetable intake has been associated with reduced risk of hypertension; however, results have been inconsistent and it is unclear whether specific types of fruits and vegetables are particularly beneficial. This systematic review and meta-analysis aimed to summarize the published prospective studies on fruit and vegetable consumption and risk of hypertension.

METHODS

Embase and PubMed databases were searched for relevant prospective studies up to 15th May 2022. Random effects models were used to calculate summary relative risks (RRs) and 95% confidence intervals (CIs) for the association between fruit and vegetable intake and risk of hypertension. Strength of evidence was assessed using World Cancer Research Fund (WCRF) criteria.

RESULTS

Eighteen prospective studies (451 291 participants, 145 492 cases) were included. The summary RR (95% CI) of hypertension per 200 g/day was 0.97 (0.95-0.99, I² = 68%, n = 8) for fruits and vegetables, 0.93 (0.89-0.98, I² = 77%, n = 10) for fruits, and 1.00 (0.98-1.02, I² = 38%, n = 10) for vegetables. Reductions in risk were observed up to 800 g/day for fruits and vegetables, and 550 g/day for fruits, and these two associations were considered probably causal using WCRF criteria. Inverse associations were observed for apples or pears, blueberries, raisins or grapes, avocado, broccoli, carrots and lettuce, while positive associations were observed for cantaloupe, Brussels sprouts, cruciferous vegetables, and total and fried potatoes (n = 2-5).

CONCLUSION

A high intake of fruit and vegetables combined, and total fruit was associated with reduced risk of hypertension, while results for fruit and vegetable subtypes were mixed and need further study.

Effect of salt reduction interventions in lowering blood pressure: A comprehensive systematic review and meta-analysis of controlled clinical trials

BACKGROUND

Excessive salt intake results in hypertension (HTN), which is a major risk factor for cardiovascular disease (CVD). This review and meta-analysis aimed to evaluate the effect of salt reduction interventions on systolic blood pressure (SBP) and diastolic blood pressure (DBP).

METHODS

Studies were identified via systematic searches of the databases, including PubMed, Embase, Scopus, and Web of Science. All the studies examining the effectiveness of salt reduction interventions on blood pressure (BP), regardless of age, sex, and HTN status, were included in the systematic review, and eligible studies were used in the meta-analysis. A random-effect model was applied for quantitative data synthesis.

RESULTS

A total of 50 trials extracted from 40 articles (21 trials on nutrition education,10 on self-help materials,17 on salt substitutes, and 2 on food reformulation) were included in the systematic review. The pooled results of 44 eligible trials showed that salt substitution and nutrition education interventions had significant effects on both SBP (WMD: -7.44 mmHg, P<0.001 and WMD: -2.75 mmHg, P<0.001, respectively), and DBP (WMD: -3.77 mmHg, P<0.001 and WMD: -2.11 mmHg, P<0.001, respectively). Furthermore, using self-help materials led to a significant reduction in SBP among subjects aged 25-60 years (WMD: -2.60 mmHg, P = 0.008); it also decreased both SBP and DBP among those who were hypertensive (WMD: -3.87 mmHg, P = 0.003 and WMD: -2.91 mmHg, P<0.001, respectively).

CONCLUSION

Our results supported that salt substitution and nutrition education are effective nutrition strategies to lower BP. It seems that multi-component approaches could be more effective in improving BP status. However, further trials are required.

A Town-Level Comprehensive Intervention Study to Reduce Salt Intake in China: Cluster Randomized Controlled Trial

We determined whether a town-level comprehensive intervention program could lower the salt intake of a population. The parallel, cluster randomized controlled trial was carried out between October 2018 and January 2020 in 48 towns from 12 counties across 6 provinces in China. All participants were asked to complete the 24 h urine collections, anthropometric measurements and questionnaires at the baseline and one-year post-intervention survey. A total of 2693 participants aged 18 to 75 years were recruited at the baseline. A total of 1347 individuals in 24 towns were allocated to the intervention group and the others were allocated to the control group. Valid information from 2335 respondents was collected in the follow-up survey. The 24-h urinary sodium excretion was 189.7 mmol/24 h for the intervention group and 196.1 mmol/24 h for the control group at baseline. At a one-year follow-up, the mean effect of salt intake did not show a significant change (p = 0.31) in the intervention group compared to the control group. However, the mean result of potassium excretion in the intervention group increased by 2.18 mmol/24 h (85.03 mg/24 h) (p = 0.004) and systolic blood pressure decreased by 2.95 mmHg (p < 0.001). The salt-related knowledge and attitude toward salt reduction improved significantly in the intervention group (p < 0.05). A longer period of intervention and follow-up assessment might be needed to evaluate the long-term effectiveness of the program on salt reduction.

Nutritional Composition, Antinutrient Contents, and Polyphenol Compounds of Selected Underutilized and Some Commonly Consumed Vegetables in East Wollega, West Ethiopia

In Ethiopia, some plants (Ethiopia kale, Swiss chard, and celery) remain underutilized for human consumption, as information on their nutritional potential remains limited. As a result, the purpose of this study was to determine the proximate, mineral, antinutrient, and phytochemical content of Ethiopia kale (Brassica carinata), Swiss chard (Beta vulgaris), carrot (Daucus carota), tomato (Lycopersicon esculentum), and cabbage (Brassica oleracea) using standard analytical methods. The moisture, crude protein, crude fiber, crude fat, total ash, total carbohydrate, and energy contents were found to be 6.44–16.62%, 6.76–33.64%, 9.19–54.86%, 0.50–4.00%, 1.00–2.75%, 7.28–68.73%, and 141.06–333.28 kcal/100 g, respectively. Ethiopia's kale had a high protein content, while celery had a high fat and fiber content. The calcium, magnesium, iron, phosphorous, potassium, zinc, and sodium content (mg/100 gdb) ranged between 8.00 and 306.00, 8.10–11.83, 0.64–4.85, 11.34–63.00, 2.83–810.00, 0.15–41.65, and 1.50–443.80 mg/100 g, respectively. Swiss chard contained magnesium, potassium, and sodium, whereas celery was high in calcium and iron. The total oxalate, condensed tannin, and phytate (mg/100 gdb) ranged as follows: 0.88–4.92, 138.27–892.19, and 69.14–265.99, respectively. Ethiopia’s kale recorded a comparatively low amount of tannin and phytate. High mineral bioavailability, such as calcium, iron, and zinc, was obtained in Ethiopia kale. The results also showed that Ethiopia's kale contained a good amount of total phenolic and flavonoid content. The findings indicated that Ethiopia kale was a significant source of protein, had low antinutrient content with high mineral bioavailability, and had the potential to formulate nutrient-rich infant and young child foods using staple cereals and pulse grains.

Dietary Vitamins A, C, and Potassium Intake Is Associated With Narrower Retinal Venular Caliber

Introduction

The retinal vasculature, a surrogate for the systemic microvasculature, can be observed non-invasively, providing an opportunity to examine the effects of modifiable factors, such as nutrient intake, on microcirculation. We aimed to investigate the possible associations of dietary nutrient intake with the retinal vessel caliber.

Methods

In this cross-sectional study, a total of 584 participants in a medical survey of Japanese descendants living in Los Angeles in 2015 underwent a dietary assessment, fundus photographic examination, and comprehensive physical and blood examinations. Retinal vessel caliber was measured using fundus photographs with a semi-automated computer system and summarized as central retinal artery and vein equivalents (CRAE and CRVE). The association between dietary nutrient intake and retinal vessel caliber was analyzed using a multivariate linear regression model adjusted for two models including potential confounders. The first model was adjusted for age and sex. The second model was adjusted for age, sex, smoking status, body mass index, hypertension, diabetes, dyslipidemia, history of coronary heart disease, and history of stroke.

Results

After adjustment of potential confounders, compared to the quartile with the lowest intake, the difference in CRVE for the highest quartile was −5.33 μm [95% confidence interval (CI): −9.91 to −0.76, P for trend = 0.02] for vitamin A, −4.93 μm (95% CI: −9.54 to −0.32, P for trend = 0.02) for vitamin C and −3.90 μm (95% CI: −8.48 to 0.69, P for trend = 0.04) for potassium.

Conclusions

A significant association was observed between higher vitamins A, C and potassium intakes and narrower retinal venular caliber.

The Development of Smoked Mackerel with Reduced Sodium Content

The World Health Organization recommends reducing salt (sodium chloride, NaCl) intake by 30% by 2025. Since smoked fish can deliver up to 4 g NaCl/100 g, the aim of this study was to develop safe, healthy and attractive smoked chub mackerel (Scomber japonicus) with a reduced NaCl content. Two brines (5% and 10%) were used with different ratios of NaCl and potassium chloride (KCl). In each brine, 0%, 25%, 50% and 75% of NaCl was replaced by KCl, resulting in 1.3, 1.1, 0.9 and 0.6 g NaCl (5% brine), and 2.6, 2.0, 1.2 and 0.8 g NaCl (10% brine) per 100 g, respectively. Similar yield, nutritional, safety, texture and colour properties were found in most formulations. The most desirable taste attributes (negligible bitterness and adequate saltiness) were obtained with a 5% brine prepared with 75% NaCl + 25% KCl. Such conditions seemed to allow for obtaining an attractive product for conscious consumers.

Randomized Trial on the Effects of Dietary Potassium on Blood Pressure and Serum Potassium Levels in Adults with Chronic Kidney Disease

In the general population, an increased potassium (K) intake lowers blood pressure (BP). The effects of K have not been well-studied in individuals with chronic kidney disease (CKD). This randomized feeding trial with a 2-period crossover design compared the effects of diets containing 100 and 40 mmol K/day on BP in 29 adults with stage 3 CKD and treated or untreated systolic BP (SBP) 120–159 mmHg and diastolic BP (DBP) <100 mmHg. The primary outcome was 24 h ambulatory systolic BP. The higher-versus lower-K diet had no significant effect on 24 h SBP (−2.12 mm Hg; p = 0.16) and DBP (−0.70 mm Hg; p = 0.44). Corresponding differences in clinic BP were −4.21 mm Hg for SBP (p = 0.054) and −0.08 mm Hg for DBP (p = 0.94). On the higher-K diet, mean serum K increased by 0.21 mmol/L (p = 0.003) compared to the lower-K diet; two participants had confirmed hyperkalemia (serum K ≥ 5.5 mmol/L). In conclusion, a higher dietary intake of K did not lower 24 h SBP, while clinic SBP reduction was of borderline statistical significance. Additional trials are warranted to understand the health effects of increased K intake in individuals with CKD.

Lifestyle, psychological, socioeconomic and environmental factors and their impact on hypertension during the coronavirus disease 2019 pandemic

SUMMARY

The coronavirus disease 2019 (COVID-19) pandemic considerably affects health, wellbeing, social, economic and other aspects of daily life. The impact of COVID-19 on blood pressure (BP) control and hypertension remains insufficiently explored. We therefore provide a comprehensive review of the potential changes in lifestyle factors and behaviours as well as environmental changes likely to influence BP control and cardiovascular risk during the pandemic. This includes the impact on physical activity, dietary patterns, alcohol consumption and the resulting consequences, for example increases in body weight. Other risk factors for increases in BP and cardiovascular risk such as smoking, emotional/psychologic stress, changes in sleep patterns and diurnal rhythms may also exhibit significant changes in addition to novel factors such as air pollution and environmental noise. We also highlight potential preventive measures to improve BP control because hypertension is the leading preventable risk factor for worldwide health during and beyond the COVID-19 pandemic.

High Concentration of Heavy Metal and Metalloid Levels in Edible Campomanesia adamantium Pulp from Anthropic Areas

This study aimed to quantify the extent of heavy metal, non-metal and metalloid levels in the Campomanesia adamantium pulp obtained from an area crossed by road experiencing high large vehicle traffic and intensive agriculture modern farming, to monitor the health risks associated with pulp consumption by humans. For this purpose, in three spots located within this area, ripe fruits were collected on the roadside, bush and farm-margin. Pulp samples were digested by microwave-assisted equipment, and chemical elements were quantified by ICP OES. The concentrations of K, Pb, Se, Fe, Mo, Zn, Co, Ni and Mn in the pulp collected in roadside/bush points showed statistical differences (p < 0.05). The heavy metals and metalloid concentrations that exceeded FAO/WHO standards were ordered Pb > As > Mo > Co > Ni > Mn > Cr. Therefore, among these metalloid and heavy metals, As, Pb and Cr were found to be higher in farm-margin > roadside > bush (1.5 × 10⁻³, 1.1 × 10⁻³ and 6.2 × 10⁻⁴), respectively. Therefore, As is the most important metalloid with higher levels in farm-margin, roadside and bush (1.5 × 10⁻³, 1.0 × 10⁻³ and 6.0 × 10⁻⁴ > 10⁻⁶–10⁻⁴ and 3.33, 2.30 and 1.34 > 1), respectively, to total cancer risk and hazard quotient, if 10 g daily of pulp are consumed.

Plant foods, dietary fibre and risk of ischaemic heart disease in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort

BACKGROUND

Epidemiological evidence indicates that diets rich in plant foods are associated with a lower risk of ischaemic heart disease (IHD), but there is sparse information on fruit and vegetable subtypes and sources of dietary fibre. This study examined the associations of major plant foods, their subtypes and dietary fibre with risk of IHD in the European Prospective Investigation into Cancer and Nutrition (EPIC).

METHODS

We conducted a prospective analysis of 490 311 men and women without a history of myocardial infarction or stroke at recruitment (12.6 years of follow-up, n cases = 8504), in 10 European countries. Dietary intake was assessed using validated questionnaires, calibrated with 24-h recalls. Multivariable Cox regressions were used to estimate hazard ratios (HR) of IHD.

RESULTS

There was a lower risk of IHD with a higher intake of fruit and vegetables combined [HR per 200 g/day higher intake 0.94, 95% confidence interval (CI): 0.90-0.99, P-trend = 0.009], and with total fruits (per 100 g/day 0.97, 0.95-1.00, P-trend = 0.021). There was no evidence for a reduced risk for fruit subtypes, except for bananas. Risk was lower with higher intakes of nuts and seeds (per 10 g/day 0.90, 0.82-0.98, P-trend = 0.020), total fibre (per 10 g/day 0.91, 0.85-0.98, P-trend = 0.015), fruit and vegetable fibre (per 4 g/day 0.95, 0.91-0.99, P-trend = 0.022) and fruit fibre (per 2 g/day 0.97, 0.95-1.00, P-trend = 0.045). No associations were observed between vegetables, vegetables subtypes, legumes, cereals and IHD risk.

CONCLUSIONS

In this large prospective study, we found some small inverse associations between plant foods and IHD risk, with fruit and vegetables combined being the most strongly inversely associated with risk. Whether these small associations are causal remains unclear.

Heterozygosity for a Pathogenic Variant in SLC12A3 That Causes Autosomal Recessive Gitelman Syndrome Is Associated with Lower Serum Potassium

BACKGROUND

Potassium levels regulate multiple physiologic processes. The heritability of serum potassium level is moderate, with published estimates varying from 17% to 60%, suggesting genetic influences. However, the genetic determinants of potassium levels are not generally known.

METHODS

A whole-exome sequencing association study of serum potassium levels in 5812 subjects of the Old Order Amish was performed. A dietary salt intervention in 533 Amish subjects estimated interaction between p.R642G and sodium intake.

RESULTS

A cluster of variants, spanning approximately 537 kb on chromosome 16q13, was significantly associated with serum potassium levels. Among the associated variants, a known pathogenic variant of autosomal recessive Gitelman syndrome (p.R642G SLC12A3) was most likely causal; there were no homozygotes in our sample. Heterozygosity for p.R642G was also associated with lower chloride levels, but not with sodium levels. Notably, p.R642G showed a novel association with lower serum BUN levels. Heterozygotes for p.R642G had a two-fold higher rate of self-reported bone fractures and had higher resting heart rates on a low-salt diet compared with noncarriers.

CONCLUSIONS

This study provides evidence that heterozygosity for a pathogenic variant in SLC12A3 causing Gitelman syndrome, a canonically recessive disorder, contributes to serum potassium concentration. The findings provide insights into SLC12A3 biology and the effects of heterozygosity on electrolyte homeostasis and related subclinical phenotypes that may have implications for personalized medicine and nutrition.

Hungry Rice-based Biscuits: Effects on Some Biochemical Indices of Alloxan- induced Diabetic Adult Male Wistar Rats

Background:

High costs of hypoglycemic drugs and their side effects have caused an increase in demand for the production of low glycemic plant foods and snacks from locally available nutrient dense crops for diabetes management. Hungry rice is known for its high fiber content and hypoglycemic properties.

Objectives:

The study investigated the effect of Hungry rice-based biscuits on some biochemical indices of alloxan-induced diabetic Wistar rats.

Methods:

Four groups of six adult male Wistar rats each with a mean weight of 164.59 g were fasted overnight and induced diabetes by a single intraperitoneal injection of alloxan at a dose of 150 mg/kg body weight and fed biscuits containing hungry rice/unripe plantain/cashew nut (80:10:10%), hungry rice/unripe-plantain (80:20%), hungry rice/cashew nut (80:20%) or wheat (100%) and water ad libitum for 21 days. The non-induced rats fed poultry growers’ mash serve as the control. The rats’ body weight and food intake were evaluated while the lipid profile, liver enzyme markers, and serum protein were assayed.

Results:

Hungry rice-based biscuits showed decreases in fasting blood glucose, AST, ALT, ALP, TC, TG, and LDL-C and increases in HDL-C and total serum protein of rats. ALP and serum protein were more in rats fed Wheat biscuit and 80% hungry rice-20% unripe plantain biscuit. The biscuit containing 20% cashew nut showed a better desirable effect on all the parameters tested.

Conclusion:

The hungry rice-based-biscuits exhibited hypoglycemic and hypolipidemic potentials with desirable effect on liver biomarkers and serum proteins; and may be good for diabetes and weight management.

The effectiveness, feasibility, and acceptability of low-sodium salts worldwide: An environmental scan protocol

Excess sodium intake elevates blood pressure and risk for cardiovascular diseases. The use of low-sodium salts is a potentially cost-effective strategy to counter the rising global burden of cardiovascular diseases. This research aimed to understand the potential scale-up of low-sodium salt interventions by examining the availability of low-sodium salts globally, synthesizing evidence about the effectiveness of low-sodium salt interventions, and identifying the challenges and opportunities associated with implementing low-sodium salt interventions. This study consists of three parts. The first part is a systematic online search of low-sodium salts. The authors will use the advanced search functions of search engines and online shopping sites to execute the search. The second part is a systematic review of academic literature on the use of low-sodium salts. A meta-analysis will be performed to quantify the effectiveness of low-sodium salt interventions. The third part is key informant interviews to understand the challenges of implementing low-sodium salt interventions. Key informants will include policymakers, academic researchers, and salt industry representatives. The list of key informants will be generated through purposive sampling and snowball sampling based on the completed online search and the systematic review. The interview guides will be developed based on the RE-AIM (Reach, Effective, Adoption, Implementation, and Maintenance) framework. The study received ethics approval from the University of New South Wales Human Research Ethics Advisory Panel (HC190921). Findings will be disseminated with academics and policymakers through a peer-reviewed journal and conference presentations.

Effect of Organic Fertilizers on Selected Health Beneficial Bioactive Compounds and Aroma Profile of Red Topepo Sweet Pepper

Phytochemicals and antioxidant properties of red sweet pepper cv Topepo grown in soil amended with different organic fertilizers were compared with that grown in unamended soil. Organic fertilizers are an environmentally friendly alternative to recovery infertile soils that resulted from the intensified agricultural practices in red Topepo production. The aim was to discriminate the effects of organic fertilizers one from each other on the quality of red Topepo to find out the better sustainable fertilization practice for its cultivation. Results showed that compost from vegetable residues (CV) enhanced the synthesis of total phenols, flavonoids, ascorbic acid, vitamin E, carotenoids, anthocyanins, as well as carbohydrates, antioxidant activities, and aroma profiling, compared to horse manure (HD), compost from olive pomace (CO), and control (CTR). The results indicated a specificity between the quality of red Topepo and compost composition, highlighting that vegetable residues increased the synthesis of secondary metabolites, enhancing sustainably, the nutraceutical, sensorial, and economic value of red Topepo. The fertilizer composition resulted largely responsible for the synthesis of bioactive compounds, flavor, and aroma of this fruit.

Identifying Interactions between Dietary Sodium, Potassium, Sodium-Potassium Ratios, and FGF5 rs16998073 Variants and Their Associated Risk for Hypertension in Korean Adults

Hypertension is affected by both genetic and dietary factors. This study aimed to examine the interaction between dietary sodium/potassium intake, sodium–potassium ratios, and FGF5 rs16998073 and link these with increased risk for developing hypertension. Using data from the Health Examinee (HEXA) Study of the Korean Genome and Epidemiologic Study (KoGES), we were able to identify a total of 17,736 middle-aged Korean adults who could be included in our genome-wide association study (GWAS) to confirm any associations between hypertension and the FGF5 rs16998073 variant. GWAS analysis revealed that the FGF5 rs16698073 variant demonstrated the strongest association with hypertension in this population. Multivariable logistic regression was used to examine the relationship between dietary intake of sodium, potassium, and sodium–potassium ratios and the FGF5 rs16998073 genotypes (AA, AT, TT) and any increased risk of hypertension. Carriers with at least one minor T allele for FGF5 rs16998073 were shown to be at significantly higher risk for developing hypertension. Male TT carriers with a daily sodium intake ≥2000 mg also demonstrated an increased risk for developing hypertension compared to the male AA carriers with daily sodium intake <2000 mg (adjusted odds ratio (AOR) = 2.41, 95% confidence intervals (CIs) = 1.84–3.15, p-interaction < 0.0001). Female AA carriers with a daily potassium intake ≥3500 mg showed a reduced risk for hypertension when compared to female AA carriers with a daily potassium intake <3500 mg (AOR = 0.75. 95% CIs = 0.58–0.95, p-interaction < 0.0001). Male TT carriers in the mid-tertile for sodium–potassium ratio values showed the highest odds ratio for hypertension when compared to male AA carriers in the lowest-tertile for sodium–potassium ratio values (AOR = 3.03, 95% CIs = 2.14–4.29, p-interaction < 0.0001). This study confirmed that FGF5 rs16998073 variants do place their carriers (men and women) at increased risk for developing hypertension. In addition, we showed that high daily intake of sodium exerted a synergistic effect for hypertension when combined with FGF5 rs16998073 variants in both genders and that dietary sodium, potassium, and sodium–potassium ratios all interact with FGF5 rs16998073 and alter the risk of developing hypertension in carriers of either gender among Koreans.

Mineral Intake Status of Community-Dwelling Elderly from Urban and Rural Areas of South Korea: A Cross-Sectional Study Based on Korean National Health and Nutrition Examination Survey, 2013~2016

We aimed to evaluate the intake of minerals (calcium, phosphorous, sodium, and potassium) in the urban and rural elderly and explore the adequacy of intake and food sources for each mineral using nationwide big data. The study used data from the Korea National Health and Nutrition Examination Survey (KNHANES) between 2013 and 2016. We analyzed 5292 elderly individuals that were aged 65 years and older (2271 men, 3021 women). Daily calcium, phosphorous, sodium, and potassium intake, and they were analyzed using the 24-h dietary recall method. Additionally, the adequacy of intake and food sources for each mineral was analyzed. Blood triglyceride level was significantly higher in rural elderly than in urban elderly. The intake of calcium and potassium per 1000 kcal of energy intake was significantly lower in the rural elderly, and the proportion of participants with calcium intake below the Estimated Average Requirement was significantly higher in the rural elderly than in the urban elderly. The intake of calcium, phosphorous, and potassium in the rural elderly was lower than that in the urban elderly. These results can be used as basic data when making social and environmental policies for the health of the elderly and when providing targeted dietary education for the management of chronic diseases for the elderly.

Biosynthesis of Bonelike Apatite 2D Nanoplate Structures Using Fenugreek Seed Extract

An innovative, biomimetic, green synthesis approach was exploited for the synthesis of humane and environmental friendly nanomaterials for biomedical applications. Ultrafine bonelike apatite (BAp) 2D plate-like structures were prepared using fenugreek seed extract during the biosynthesis wet-chemical precipitation route. The chemical analysis, morphology and structure of the prepared 2D nanoplates were characterized by inductively coupled plasma atomic emission spectroscopy (ICP-OES), electron microscopy (SEM and TEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. A 2D plate-like nanostructure of BAp with an average width (length) of 12.67 ± 2 nm and thickness of 3.8 ± 1.2 nm was obtained. BAp 2D crystals were tuned by interaction with the fenugreek organic molecules during the fabrication process. In addition to Ca and P ions, bone mineral sources such as K, Mg, Na, SO₄ and CO₃ ions were incorporated into BAp nanoplates using fenugreek seed extract. The overall organic molecule concentration in the reaction process increased the effectiveness of hydroxyl groups as nucleation sites for BAp crystals. Accordingly, the size of the biosynthesized BAp plate-like structure was reduced to its lowest value. Biosynthesis BAp 2D plate-like nanocrystals showed good viability and higher growth of MC3T3 osteoblast-like structures than that of the control sample. BAp 2D nanoplates prepared by a facile, ecofriendly and cost-effective approach could be considered a favorable osteoconductive inorganic biomaterial for bone regeneration applications.

[Expert Council Resolution. Practical Aspects of the Diagnosis and Correction of Potassium and Magnesium Deficiency States]

The article analyzes properties of potassium and magnesium, which may exert vasodilatory, anti-inflammatory, anti-ischemic, antiaggregant, and antiarrhythmic effects. These are extremely important microelements and potentially beneficial therapeutic agents for treatment of cardiovascular diseases.

Positive Association of Dietary Inflammatory Index with Incidence of Cardiovascular Disease: Findings from a Korean Population-Based Prospective Study

Recently, diets with higher inflammatory potentials based on the dietary inflammatory index (DII^®) have been shown to be associated with increased cardiovascular disease (CVD) risk in the general population. We aimed to prospectively investigate the association between the DII and CVD risk in the large Korean Genome and Epidemiology Study_Health Examination (KoGES_HEXA) cohort comprised of 162,773 participants (men 55,070; women 107,703). A validated semi-quantitative food frequency questionnaire (SQ-FFQ) was used to calculate the DII score. Statistical analyses were performed by using a multivariable Cox proportional hazard model. During the mean follow-up of 7.4 years, 1111 cases of CVD were diagnosed. Higher DII score was associated with increased risk of CVD in men (hazard ratio [HR]_{Quintile 5 vs. 1} 1.43; 95% CI 1.04–1.96) and in women (HR_{Quintile 5 vs. 1} 1.19; 95% CI 0.85–1.67), although not significant for women. The risk of CVD was significantly higher in physically inactive men (HR_{Quintile 5 vs. 1} 1.80; 95% CI 1.03–3.12), obese men (HR_{Quintile 5 vs. 1} 1.77; 95% CI 1.13–2.76) and men who smoked (HR_{Quintile 5 vs. 1} 1.60; 95% CI 1.10–2.33), respectively. The risk of developing stroke was significantly higher for men (HR_{Quintile 5 vs. 1} 2.06; 95% CI 1.07–3.98; p = 0.003), but not for women. A pro-inflammatory diet, as indicated by higher DII scores, was associated with increased risk of CVD and stroke among men.

Should we eat more potassium to better control blood pressure in hypertension?

Changes in lifestyle and nutrition are recommended as the first-step approach to the management of hypertension by all national and international guidelines. Today, when considering nutritional factors in hypertension, almost all the attention is focused on the reduction of salt intake to improve blood pressure (BP) control. Changes in potassium intake are only briefly evoked in guidelines. Few physicians actually think about proposing to eat more foods that are high in potassium (fruits, vegetables, nuts) to better control BP. Yet, during the last 40 years, increasing evidence has accumulated demonstrating that increasing potassium intake, either with food products or with supplements, is associated with significant reductions of both systolic and diastolic BP. The hypotensive effect of potassium is particularly marked in patients with hypertension and in subjects with a very high sodium intake, suggesting that potassium counterbalances the effects of sodium. In addition, several meta-analyses have now confirmed that high potassium intake reduces the risk of stroke by ∼ 25%. Finally, increasing potassium in the diet may perhaps be beneficial for some renal patients, as post hoc analyses have suggested that a high potassium intake may retard the decline of renal function in patients with early chronic kidney disease (CKD) stages. However, high potassium intake may be risky and sometimes even dangerous in hypertensive patients with CKD stages 3-5, specifically diabetics. In this context, however, as the level of evidence remains low, more prospective clinical studies are needed. The goal of this review is to discuss the actual evidence that supports the recommendation to eat more potassium in order to better control BP in essential hypertension and to review the restrictions in CKD patients with hypertension.

Dietary Sodium Intake and Food Sources Among Chinese Adults: Data from the CNNHS 2010-2012

The present study was done to examine the status of dietary sodium intake and dietary sources of sodium among Chinese adults. Data were obtained from China National Nutrition and Health Surveillance (CNNHS) 2010–2012. All adults recruited in this study provided complete dietary data on three-day consecutive 24-h dietary recalls combining with the household weighing method. Sodium intake was adjusted for energy to 2000 kcal/day using the residual method. Average sodium intake was 5013 (95% Confidence Interval, CI: 4858, 5168) mg/day, and 92.6% of adults’ sodium intake exceeded the standard in the Chinese proposed intake for preventing non-communicable chronic diseases (PI-NCD). The salt added to food was the main contributor to daily sodium intake, representing 69.2% of the total sodium consumption. The proportion of sodium from salt was different in some subgroups. The contribution ranged from 64.8% for those who came from urban areas aged 18–49 years old to 74.7% for those who came from rural areas with education levels of primary school or less, and sodium from soy sauce was the next highest contributor (8.2%). The proportion of the subjects with sodium intake contributed by flour products was higher in the north with 7.1% than the south with 1.4%. The average consumption of sodium among Chinese was more than the recommended amount, and salt was the main source of sodium.

Twenty-Four-Hour Urinary Sodium and Potassium Excretion in China: A Systematic Review and Meta-Analysis

Background

In China, high sodium and low potassium intakes result in elevated blood pressure, a major cause of cardiovascular disease, yet the intake estimates lack accuracy and nutritional strategies remain limited.

Methods and Results

We aimed to determine sodium and potassium intake by systematically searching for and quantitatively summarizing all published 24‐hour urinary sodium and potassium data (ie, the most accurate method). MEDLINE, EMBASE, Scopus, China National Knowledge Infrastructure, and Wanfang were searched up to February 2019. All studies reporting 24‐hour urinary sodium or potassium in China were included; hospitalized patients were excluded. Data were pooled using random‐effects meta‐analysis and heterogeneity was explored with meta‐regression. Sodium data were reported in 70 studies (n=26 767), 59 of which also reported potassium (n=24 738). Mean sodium and potassium excretions were 86.99 mmol/24 h (95% CI, 69.88–104.10) and 14.65 mmol/24 h (95% CI, 11.10–18.20) in children aged 3 to 6 years, 151.09 mmol/24 h (95% CI, 131.55–170.63) and 25.23 mmol/24 h (95% CI, 22.37–28.10) in children aged 6 to 16 years, and 189.07 mmol/24 h (95% CI, 182.14–195.99) and 36.35 mmol/24 h (95% CI, 35.11–37.59) in adults aged >16 years. Compared with southern China, sodium intake was higher in northern China (P<0.0001) but is declining (P=0.0066).

Conclusions

Average sodium intake in all age groups across China is approximately double the recommended maximum limits, and potassium intake is less than half that recommended. Despite a decline, sodium intake in northern China is still among the highest in the world, and the North–South divide persists. Urgent action is needed to simultaneously reduce sodium and increase potassium intake across China.

Postulating the major environmental condition resulting in the expression of essential hypertension and its associated cardiovascular diseases: Dietary imprudence in daily selection of foods in respect of their potassium and sodium content resulting in oxidative stress-induced dysfunction of the vascular endothelium, vascular smooth muscle, and perivascular tissues

We hypothesize that the major environmental determinant of the expression of essential hypertension in America and other Westernized countries is dietary imprudence in respect of the consumption of daily combinations of foods containing suboptimal amounts of potassium and blood pressure-lowering phytochemicals, and supraphysiological amounts of sodium. We offer as premise that Americans on average consume suboptimal amounts of potassium and blood pressure-lowering phytochemicals, and physiologically excessive amounts of sodium, and that such dietary imprudence leads to essential hypertension through oxidative stress-induced vascular endothelial and smooth muscle dysfunction. Such dysfunctions restrict nitric oxide bioavailability, impairing endothelial cell-mediated relaxation of the underlying vascular smooth muscle, initiating and maintaining inappropriately increased peripheral and renal vascular resistance. The biochemical steps from oxidative stress to vascular endothelial dysfunction and its pernicious cardiovascular consequences are well established and generally accepted. The unique aspect of our hypothesis resides in the contention that Americans' habitual consumption of foods resulting in suboptimal dietary intake of potassium and supraphysiological intake of sodium result in oxidative stress, the degree of which, we suggest, will correlate with the degree of deviation of potassium and sodium intake from optimal. Because suboptimal intakes of potassium reflect suboptimal intakes of fruits and vegetables, associated contributors to oxidative stress include suboptimal intakes of magnesium, nitrate, polyphenols, carotenoids, and other phytochemical antioxidants for which fruits and vegetables contain abundant amounts. Currently Americans consume potassium-to-sodium in molar ratios of less than or close to 1.0 and the Institute of Medicine (IOM) recommends a molar ratio of 1.2. Ancestral diets to which we are physiologically adapted range from molar ratios of 5.0 to 10.0 or higher. Accordingly, we suggest that the average American is usually afflicted with oxidative stress-induced vascular endothelial dysfunction, and therefore the standards for normal blood pressure and pre-hypertension often reflect a degree of clinically significant hypertension. In this article, we provide support for those contentions, and indicate the findings that the hypothesis predicts.

Relationship between lifespan indicators and elemental background values: A case study in Guangdong Province, China

There was a significant difference in the distribution of centenarians at county-level in Guangdong Province, China. To carry out an integrated analysis on elemental background values and their relation to lifespan level, samples of environmental media such as drinking water, staple rice and soil were collected in ten counties (non-longevity and longevity areas) in Guangdong Province. Meanwhile, lifespan indicators were calculated based on census data in 2010: the percentage of population aged 80 to 90years (octogenarian index, 80-90%, OI%), the percentage of population aged 90 to 100years (longevity index, 90-100%, LI%), centenarians per one hundred thousand inhabitants (CH). Grey relational analysis (GRA) and stepwise multiple linear regression analysis (SMLR) were conducted. The major results show that the contents of Se, Mo, Ni, K and Zn in drinking water and rice and the content of Se in soil in longevity areas are significantly higher than those in non-longevity areas. Significantly positive correlation between elemental background values (Se, K, Mo, Ni and Zn) and three lifespan indicators shows an increasing trend in the order of OI, LI and CH. However, element Al in rice and soil shows a negative correlation with CH. In addition, the influence degree of elemental background values on LI and CH can be ranked as Se>Mo>K>Zn>Ni. The explanatory power of elemental background values (Se, K, Mo, Ni and Zn) to difference in LI/CH in longevity and non-longevity areas can be ranked: drinking water>rice>soil. The elemental background values (Se, K, Mo, Ni and Zn) have a positive impact on human lifespan, especially for those who live longer than 90years old.

Is sodium and potassium content of commonly consumed processed packaged foods a cause of concern?

Processed foods are the major contributors towards sodium intake thereby pre-disposing individuals towards risk of Diet Related Non-communicable Diseases (DR-NCDs). There is paucity of data on sodium and potassium content of processed packaged foods in India. The sodium and potassium content of the most commonly consumed processed packaged foods (n=154) was analyzed by AOAC 969.23 method using Flame Photometer. Highest analyzed mean sodium content was found in soups (4823±1674mg/100g, range=3220 to 8000mg/100g) while the potassium content was highest in chips with a mean of 778±260mg/100g and ranged between 360 and 1220mg/100g. A higher potassium to sodium ratio is desirable for good health, however only 20% of the analyzed products were found to have the same. Therefore, there is a need to monitor the sodium and potassium content of the processed packaged foods and to reformulate the products to bring about favorable potassium to sodium ratio.

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.

Systematic review and meta-analysis of randomised controlled trials on the effects of potassium supplements on serum potassium and creatinine

OBJECTIVES

High potassium intake could prevent stroke, but supplementation is considered hazardous. We assessed the effect of oral potassium supplementation on serum or plasma potassium levels and renal function.

SETTING

We updated a systematic review of the effects of potassium supplementation in randomised clinical trials carried out worldwide, published in 2013, extending it to July 2015. We followed the PRISMA guidelines.

PARTICIPANTS

Any individual taking part in a potassium supplementation randomised clinical trial. Studies included met the following criteria: randomised clinical trials, potassium supplement given and circulating potassium levels reported.

INTERVENTION

Oral potassium supplementation.

PRIMARY OUTCOME MEASURES

Serum or plasma potassium and serum or plasma creatinine.

RESULTS

A total of 20 trials (21 independent groups) were included (1216 participants from 12 different countries). All but 2 were controlled (placebo n=16, control n=2). Of these trials, 15 were crossover, 4 had a parallel group and 1 was sequential. The duration of supplementation varied from 2 to 24 weeks and the amount of potassium given from 22 to 140 mmol/day. In the pooled analysis, potassium supplementation caused a small but significant increase in circulating potassium levels (weighted mean difference (WMD) 0.14 mmol/L, 95% CI 0.09 to 0.19, p<1×10(-5)), not associated with dose or duration of treatment. The average increase in urinary potassium excretion was 45.75 mmol/24 hours, 95% CI 38.81 to 53.69, p<1×10(-5). Potassium supplementation did not cause any change in circulating creatinine levels (WMD 0.30 µmol/L, 95% CI -1.19 to 1.78, p=0.70).

CONCLUSIONS

In short-term studies of relatively healthy persons, a moderate oral potassium supplement resulted in a small increase in circulating potassium levels and no change in renal function.

Relationships between micronutrient losses in sweat and blood pressure among heat-exposed steelworkers

We aimed to examine the effect of micronutrient losses through sweat on blood pressure (BP) among heat-exposed steelworkers. A total of 224 heat-exposed male steelworkers from an ironworks facility were evaluated in July 2012. We measured the Wet Bulb Globe Temperature Index to evaluate the level of heat stress in the workplace. We collected sweat from the workers during an eight-hour work, and then we measured the micronutrients in the sweat. We also measured the BP of each worker. The results revealed that vitamin C, potassium, and calcium losses in sweat were positively correlated with systolic (SBP) and diastolic (DBP) blood pressure (all P<0.05). A linear stepwise regression analysis revealed that potassium, and calcium losses in sweat adversely affected SBP and DBP (all P<0.05). An analysis of covariance showed that SBP increased when potassium or calcium losses in sweat were >900 mg, or >100 mg, respectively. Further, DBP increased when potassium or calcium losses in sweat were >600 mg or >130 mg, respectively. Therefore, vitamin C, potassium, and calcium losses in sweat may adversely effect BP. To help steelworkers maintain healthy BP, facilities with high temperatures should try to lower environmental temperatures to reduce vitamin C, potassium, and calcium losses in sweat. Additionally, heat-exposed steelworkers may need to increase their dietary intakes of vitamin C, potassium, and calcium. Further research is needed to confirm these findings and support these recommendations.

Food groups associated with a reduced risk of 15-year all-cause death

BACKGROUND/OBJECTIVES

Long-term observational cohorts provide the opportunity to investigate the potential impact of dietary patterns on death. We aimed to investigate all-cause death according to the consumption of selected food groups, and then to identify those independently associated with reduced mortality.

SUBJECTS/METHODS

Population survey of middle-aged men randomly selected in the period 1995-1997 from the general population of three French areas and followed over a median of 14.8 years. Dietary data were collected through a 3-day food record. Cox modeling was used to assess the risk of death according to selected foods groups after extensive adjustment for confounders, including a diet quality index.

RESULTS

The study population comprised 960 men (mean age 55.5 ±6.2 years). After a median follow-up of 14.8 (interquartile range 14.3-15.2) years, 150 (15.6%) subjects had died. Food groups that remained independently predictive of a lower risk of death after extensive adjustment were an above-median consumption of milk (adjusted relative risk: 0.61, 95% confidence interval (CI): 0.43-0.86, P-value=0.005), fruits and vegetables (0.68, 0.46-0.98, P-value=0.041) and a moderate consumption of yogurts and cottage cheese (0.50, 95% CI: 0.31-0.81, P-value=0.005), other cheeses (0.62, 0.39-0.97, P-value=0.036) and bread (0.57, 0.37-0.89, P-value=0.014). Besides, there was a nonsignificant trend for a higher risk of death associated with highest sodium intakes.

CONCLUSIONS

Consumption of food groups that largely match recommendations is associated with a reduced risk of all-cause death in men. A diet providing moderate amounts of diverse food groups appears associated with the highest life expectancy.

Effect of lipid peroxidation, antioxidants, macro minerals and trace elements on eczema

The exact etiology and pathogenesis of eczema are not yet fully understood, although different factors are considered as pathogenic mechanisms in the development of eczema. Our study was designed to determine extent of serum lipid peroxidation, antioxidants, macro minerals and trace elements in patients with eczema, and thereby, find any pathophysiological correlation. The study was conducted as a case-control study with 65 eczema patients as cases and 65 normal healthy individuals as controls. Lipid peroxidation was assessed by measuring the serum level of malondialdehyde (MDA). Antioxidants- vitamin A and E concentration was determined by RP-HPLC method whereas vitamin C was evaluated for serum ascorbic acid by UV spectrophotometric method. Serum macro minerals (Na, K, Ca) and trace elements (Zn, Fe) were determined by Atomic Absorption Spectroscopy (AAS). This study found significantly higher level of MDA (p < 0.001) and lower level of antioxidants (p < 0.05) in patients in comparison to the control subjects. Analysis of serum macro minerals (Na, K and Ca) and trace elements (Zn, Fe) found that the mean values of Na, K, Ca, Zn and Fe were 2771.60 ± 75.64, 66.33 ± 3.03, 48.41 ± 2.50, 0.30 ± 0.02 and 0.29 ± 0.009 mg/L for the patient group and 3284.81 ± 34.51, 162.18 ± 3.72, 87.66 ± 2.10, 0.75 ± 0.06 and 0.87 ± 0.06 mg/L for the control group, accordingly. There was a significant difference for all the minerals between the patients and controls (p < 0.001). This study suggests a strong association between the pathogenesis of eczema with the elevated level of MDA and depleted level of antioxidants, macro minerals, and trace elements.

Low serum potassium concentration is a predictor of chronic kidney disease

AIMS

The aim of this study was to examine whether low serum potassium concentration could be a predictor of chronic kidney disease (CKD) in a community-based cohort.

MATERIALS AND METHODS

We enrolled 1001 subjects, median period of 5.7 years, and evaluated the risk factors for CKD, defined as estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73 m(2), and assessed whether low serum potassium concentration could predict CKD.

RESULTS

Compared with the subjects without development of CKD, age, body mass index, fasting plasma glucose, uric acid (UA), creatinine and serum sodium concentration were higher, and serum potassium concentration was lower in subjects with development of CKD. Univariate Cox regression analyses demonstrated that age, body mass index, fasting plasma glucose, UA, creatinine, serum sodium concentration and serum potassium concentration were associated with progression of CKD. Multiple Cox regression analysis revealed that age, gender, creatinine and serum potassium concentration were independent predictors of CKD after adjustment for covariates. When serum potassium concentration was below 4.0 mmol/l at baseline, hazard ratio (95% confidence interval) of developing CKD was 2.65 (2.04-3.44; p < 0.0001).

CONCLUSIONS

Serum potassium concentration could be a clinically relevant risk factor for the progression of CKD, defined as eGFR < 60 ml/min/1.73 m(2) , in healthy subjects.

Life-threatening hyperkalemia in a patient with normal renal function

With media focus on benefits from reducing sodium intake, there is increased popularity of salt substitutes, typically potassium chloride. While viewed by the public as a healthy alternative to standard table salt, less appreciated is the severe risk with certain comorbidities and medications. We report the case of an elderly female with chronically high salt substitute intake, normal renal function, diabetes, hypertension treated with angiotensin-converting enzyme inhibitor and beta blockade, who developed life-threatening hyperkalemia after a minimally invasive outpatient procedure. We describe the pathophysiology of the disruption in potassium homeostasis and emphasize the importance of dietary history and educating high-risk patients to avoid salt substitutes.

Potassium and health

Potassium was identified as a shortfall nutrient by the Dietary Guidelines for Americans 2010 Advisory Committee. The committee concluded that there was a moderate body of evidence of the association between potassium intake and blood pressure reduction in adults, which in turn influences the risk of stroke and coronary heart disease. Evidence is also accumulating of the protective effect of adequate dietary potassium on age-related bone loss and reduction of kidney stones. These benefits depend on organic anions associated with potassium as occurs in foods such as fruits and vegetables, in contrast to similar blood pressure-lowering benefits of potassium chloride. Benefits to blood pressure and bone health may occur at levels below current recommendations for potassium intake, especially from diet, but dose-response trials are needed to confirm this. Nevertheless, intakes considerably above current levels are needed for optimal health, and studies evaluating small increases in fruit and vegetable intake on bone and heart outcomes for short periods have had disappointing results. In modern societies, Western diets have led to a decrease in potassium intake with reduced consumption of fruits and vegetables with a concomitant increase in sodium consumption through increased consumption of processed foods. Consumption of white vegetables is associated with decreased risk of stroke, possibly related to their high potassium content. Potatoes are the highest source of dietary potassium, but the addition of salt should be limited. Low potassium-to-sodium intake ratios are more strongly related to cardiovascular disease risk than either nutrient alone. This relationship deserves further attention for multiple target tissue endpoints.

Diet and cardiovascular disease

This paper describes the importance of diet in cardiovascular disease prevention. Different aspects of diet are discussed: nutrients, single foods/food groups and dietary patterns. The evidence regarding the impact of diet on intermediate risk factors (such as blood pressure and cholesterol levels) and the impact on cardiovascular endpoints are discussed.

Associations of plasma atrial natriuretic peptide and electrolyte levels with essential hypertension

This study aimed to investigate the associations among the levels of plasma atrial natriuretic peptide (ANP) and electrolytes and essential hypertension (EH) in Uygur, Han and Kazakh populations in Xinjiang. A total of 724 hypertensive participants of different ethnicities from Xinjiang (208 Uygur, 287 Han and 229 Kazakh) and 741 normal controls (208 Uygur, 267 Han and 266 Kazakh) were enrolled. The associations of ANP with serum potassium, serum sodium and blood pressure were assessed. In the normal control (NT) group, the concentration of ANP was higher in the Uygur population than in the Han population, and the concentration in the Han population was higher than that in the Kazakh population (P<0.05). In the EH group, the serum potassium levels of the Uygur and Han populations were higher than that of the Kazakh population (P<0.05). The ANP concentration in the Uygur ethnic group was higher than that in the Han population, which was in turn higher than that in the Kazakh participants (P<0.05). In the Kazakh population, the serum potassium level was significantly lower in the EH group compared with that in the NT group (P<0.05). The serum potassium level was significantly lower and the ANP concentration significantly higher in the EH group compared with those of NT groups in the Uygur and Han populations (P<0.05). Age and body mass index (BMI) were associated with hypertension in the Uygur, Han and Kazakh populations. Low serum potassium may be a risk factor of hypertension in individuals of Uygur and Kazakh ethnicity. Plasma ANP may be a regulatory factor involved in the development of hypertension in Uygur and Han populations.

Impact of nutritional status and dietary quality on stroke: do we need specific recommendations?

Stroke, one of the most prevalent geriatric diseases, is a leading cause of death worldwide that often results in permanent physical disability and decreased quality of life, and can have a negative impact on families both financially and emotionally. Although many previous studies have shown relationships between the risk of stroke and nutritional factors, clear dietary recommendations for the prevention and reduction of stroke recurrence have not been established. Several factors should be considered to control and manage stroke. For example, a considerable number of patients with stroke are poorly nourished, have several comorbidities and undesirable health-related behaviors may be present. Stroke patients are less likely to consume beneficial foods, have poorer eating habits and have impoverished dietary quality. In addition, psychological factors such as depression must also be considered in stroke management. Given these factors, dietary recommendations for stroke patients should be established. In this article, we summarized the nutritional status and dietary quality of stroke patients. We also suggested some nutritional guidelines for stroke patients and for those who are at risk for stroke.

Long-term effects of salt substitution on blood pressure in a rural north Chinese population

Dietary sodium and potassium intake can influence blood pressure. The effects of salt substitution on patients with hypertension and normotensive family member controls, however, have not been evaluated in a rural Chinese population. The objective of this study, accordingly, was to assess the long-term effects of salt substitution on blood pressure. We conducted a double-blind, randomized controlled trial among 200 families in rural China to establish the 2-year effects of a reduced-sodium, high-potassium salt substitute (65% sodium chloride, 25% potassium chloride, 10% magnesium sulfate) compared with normal salt (100% sodium chloride) on blood pressure. Of the 462 individuals in the trial, 372 completed the study (81%). For normotensive subjects, the mean overall difference in systolic and diastolic blood pressure between the two groups at the 24-month follow-up was 2 mm Hg (95% confidence interval (CI) 0-4 mm Hg, P<0.05) and 2 mm Hg (95% CI 1-3 mm Hg, P<0.05), respectively. For subjects with hypertension, the mean overall decrease in systolic blood pressure showed a 4-mm Hg (95% CI 2-6 mm Hg, P<0.05) decrease between the two groups. Diastolic blood pressure was not affected by salt use in the hypertensive group. Salt substitution lowers systolic blood pressure in hypertensive patients and lowers both systolic and diastolic blood pressure in normotensive controls. Salt substitution, therefore, may be an effective adjuvant therapy for hypertensive patients and the potential efficacy in preventing hypertension in normotensive individuals.

Sodium and potassium intake patterns and trends in South Korea

We examined major trends and patterns regarding sodium and potassium intake and the ratio of sodium and potassium in the diets of South Koreans. We used data from 24-h dietary recall data from 10,267, 8819 and 9264 subjects ages > or =2 years in the 1998, 2005 and 2009 Korean National Health and Nutrition Examination Surveys, respectively. Mean sodium intake did not change significantly between 1998 and 2009 (4.6 vs. 4.7 g per day), while potassium intake increased significantly (2.6 vs. 2.9 g per day (P<0.001)). The major dietary sodium sources were kimchi, salt, soy sauce and soybean paste, and most potassium came from unprocessed foods (white rice, vegetables, kimchi and fruits). About 50% of the participants consumed > or =4 g of sodium per capita per day. The proportion of respondents consuming four to six grams of potassium per capita per day increased from 10.3% in 1998 to 14.3% in 2009 (P<0.001), and the sodium-potassium ratio decreased from 1.88 to 1.71 (P<0.001). One major implication is that efforts to reduce sodium in processed foods will be ineffective and future efforts must focus on both education to reduce use of sodium in food preparation and sodium replacement in salt, possibly with potassium.

Maternal history of hypertension and blood pressure response to potassium intake: the GenSalt Study

The relation between parental history of hypertension and blood pressure response to potassium intake is unknown. A 7-day high-sodium followed by a 7-day high-sodium plus potassium dietary-feeding study was conducted from 2003 to 2005 among 1,871 Chinese participants. Those with a maternal history of hypertension had larger systolic blood pressure responses to potassium compared with those without: -4.31 (95% confidence interval (CI): -4.99, -3.62) mm Hg versus -3.35 (95% CI: -4.00, -2.70) mm Hg, respectively (P(difference) = 0.002). A consistent trend was observed for diastolic blood pressure responses: -1.80 (95% CI: -2.41, -1.20) mm Hg versus -1.35 (95% CI: -1.95, -0.74) mm Hg, respectively (P = 0.07). Stronger associations between early onset maternal hypertension and blood pressure responses were noted, with systolic blood pressure decreases of -4.80 (95% CI: -5.65, -3.95) mm Hg versus -3.55 (95% CI: -4.17, -2.93) mm Hg and diastolic blood pressure decreases of -2.25 (95% CI: -3.01, -1.50) mm Hg versus -1.42 (95% CI: -1.99, -0.85) mm Hg among those with early onset maternal hypertension versus those without, respectively (P = 0.001 and 0.009, respectively). Odds ratios for high potassium sensitivity were 1.36 (95% CI: 0.96, 1.92) and 1.60 (95% CI: 1.08, 2.36) for those with maternal hypertension and early onset maternal hypertension, respectively (P = 0.08 and 0.02, respectively). Potassium supplementation could help to reduce blood pressure among those with a maternal history of hypertension.