The role of dietary potassium in hypertension and diabetes

Twenty-four-Hour Urinary Potassium Excretion, But Not Sodium Excretion, Is Associated With All-Cause Mortality in a General Population

Background

Few studies have examined the relationship between accurate monitoring of sodium or potassium consumption and mortality. We aimed to investigate the association between 24‐hour urinary sodium or potassium excretion and ≈30‐year mortality in a Japanese population using 24‐hour urine collection.

Methods and Results

We enrolled a total of 1291 participants, aged 21 to 85 years, who underwent health checkups, including a blood test and 24‐hour urine collection. They were followed up for 27.5±9.9 years by December 31, 2015, and the final follow‐up rate was 95.8%. Cox proportional hazards regression analysis was used to assess the association between 24‐hour urinary sodium or potassium excretion and all‐cause mortality. At baseline, the mean 24‐hour urinary sodium and potassium excretions were 5.80±2.28 g/d and 1.85±0.82 g/d, respectively. There were 631 deaths during the follow‐up. The cumulative survival rate was significantly decreased in the lowest quartile compared with the other higher groups. In the Cox proportional hazard model after adjustment for age and sex, 24‐hour urinary potassium excretion, but not sodium excretion, was inversely associated with all‐cause mortality. We divided the 24‐hour urinary potassium excretion levels into quartiles. After adjustment for confounding factors, the hazard ratio of all‐cause mortality in the highest quartile of 24‐hour urinary potassium excretion versus the lowest was 0.62 (95% confidence interval, 0.48–0.79; P<0.001).

Conclusions

The 24‐hour urinary potassium excretion, but not sodium excretion, was significantly associated with all‐cause mortality in the general population.

Potassium measurements and risk of type 2 diabetes: a dose-response meta-analysis of prospective cohort studies

Objective

To clarify the relationship between serum, dietary, and urinary potassium and the risk of type 2 diabetes mellitus (T2DM).

Materials and Methods

We searched PubMed and EMBASE through January 6, 2017 for studies reporting risk estimates on the association of potassium measurements and the risk of T2DM. The summary risk estimates were obtained through a random-effects model. Dose-response analysis was conducted.

Results

Eight studies involving 5,053 cases and 119,993 individuals were included. A trend toward significance was found in the highest versus lowest meta-analysis on serum potassium and T2DM risk (RR = 0.79; 95% CI 0.60-1.04); moreover, the RR per 1 mmol/L increase in serum potassium was 0.83 (95% CI 0.73-0.95). A non-significant association of dietary potassium and T2DM risk was detected (RR for the highest versus lowest category: 0.93; 95% CI 0.81-1.06; RR for every 1000mg increase per day: 1.00, 95% CI 0.96-1.05). A similar non-significant association was found for urinary potassium and T2DM risk (RR for the highest versus lowest category: 0.83; 95% CI 0.39-1.75; RR per 10 mmol increase: 1.00; 95% CI 0.95-1.05). Evidence of a linear association between serum, dietary, and urinary potassium and the risk of T2DM was found (all P_{non-linearity} > 0.05).

Conclusions

Low serum potassium increases the risk of T2DM in a linear dose-response manner; nevertheless, neither dietary potassium nor urinary potassium shows any association with the risk of T2DM. However, these findings should be interpreted with caution due to limited studies.

The Role of Healthy Lifestyle in the Primordial Prevention of Cardiovascular Disease

Whereas primary prevention seeks to forestall development of disease in individuals with elevated risk, primordial prevention seeks to preempt the development of risk factors. Health behaviors-characterized as "lifestyle" factors-are key interventional targets in primordial prevention of cardiovascular disease. Appropriate dietary intake, including limiting salt and saturated fat consumption, can reduce the risk of developing hypertension and dyslipidemias. Regular physical activity is associated with lower blood pressure and healthier lipid profiles. Diet and exercise are critical to maintaining weight conducive to cardiovascular health. Behavioral factors such as stress management, sleep duration, portion control, and meal timing may play a role in weight management and offer additional routes of intervention. Any smoking elevates cardiovascular risk. Although lifestyle modification programs can be instrumental in reaching public health goals, maintaining cardiovascular health should not be a matter solely of willpower. Ideally, structural and social forces should make healthy lifestyles the default option.

Food intake patterns and cardiovascular risk factors in Japanese adults: analyses from the 2012 National Health and nutrition survey, Japan

BACKGROUND

There is an increasing global interest in the role of Japanese diet as a possible explanation for the nation's healthy diet, which contributes to the world's highest life-expectancy enjoyed in Japan. However, nationwide studies on current food intake status among general Japanese population have not been established yet. This study examined the association between food intake patterns and cardiovascular risk factors (CVRF) such as waist circumference (WC), body mass index (BMI), blood pressure (SBP, DBP), HbA1c and blood lipid profiles among general Japanese adults.

METHODS

De-identified data on the Japan National Health and Nutrition Survey (NHNS) 2012 with a total of 11,365 subjects aged 20-84 years were applied. Food intake patterns were derived by principal component analysis (PCA) based on 98 food groups. Generalized linear regression analysis was used to assess the relation between the food intake patterns and CVRF.

RESULTS

We identified three food intake patterns: traditional Japanese, Westernized, and meat and fat patterns. Traditional Japanese pattern was significantly related to high WC and BMI in men, and high DBP in women. Westernized pattern was associated with lower SBP, but high total cholesterol and LDL cholesterol in both men and women. Meat and fat pattern was associated with high WC, high BMI, high blood pressure and blood lipid profiles in both men and women (trend P < 0.001).

CONCLUSION

The significant association between cardiovascular disease risks and three food intake patterns derived from the NHNS, showed a similar tendency to other dietary survey methods.

Effects of seed priming, salinity and methyl jasmonate treatment on bioactive composition of Brassica oleracea var. capitata (white and red varieties) sprouts

BACKGROUND

Brassica spp. sprouts are rich in nutrients and bioactive compounds, especially glucosinolates and phenolic acid derivatives, and the composition of these young germinating seeds can be altered by several external factors. In this study two cabbage varieties (Brassica oleracea var. capitata, red and white) were studied using seed priming (KCl 50 mmol L^-1 ; NaCl 150 mmol L^-1 ) and MeJA spraying (25 µmol L^-1 ) to elicit the phytochemical content of edible sprouts.

RESULTS

The red variety was richer in glucosinolates and phenolic compounds than the white one but not in mineral nutrients. Seed priming enhanced the potassium (K) content and flavonols in both varieties, while the total content of glucosinolates was reduced after seed priming only in the red variety. The white variety responded better than the red one to KCl seed priming, increasing the flavonols (89%). Salinity did not induce any change in the phytochemical content of these two varieties. Elicitation with sprayed MeJA was effective in significantly increasing the content of indolic glucosinolates glucobrassicin (5.7-fold) and neoglucobrassicin (9.7-fold) in the red cultivar. In the white variety, in addition to glucobrassicin (19.4-fold) and neoglucobrassicin (9.4-fold), 4-hydroxyglucobrassicin (2.3-fold) was also enhanced. MeJA also elicited significant amounts of anthocyanins (41%) and chlorogenic acid derivatives (329%) in the white variety.

CONCLUSION

KCl seed priming and MeJA elicitation promoted the phytochemical composition of the cabbage varieties, especially in the white variety. The application of NaCl resulted in less efficient elicitation. © 2016 Society of Chemical Industry.

Sodium and Potassium Intake in Healthy Adults in Thessaloniki Greater Metropolitan Area-The Salt Intake in Northern Greece (SING) Study

A reduction in population sodium (as salt) consumption is a global health priority, as well as one of the most cost-effective strategies to reduce the burden of cardiovascular disease. High potassium intake is also recommended to reduce cardiovascular disease. To establish effective policies for setting targets and monitoring effectiveness within each country, the current level of consumption should be known. Greece lacks data on actual sodium and potassium intake. The aim of the present study was therefore to assess dietary salt (using sodium as biomarker) and potassium intakes in a sample of healthy adults in northern Greece, and to determine whether adherence to a Mediterranean diet is related to different sodium intakes or sodium-to-potassium ratio. A cross-sectional survey was carried out in the Thessaloniki greater metropolitan area (northern Greece) (n = 252, aged 18-75 years, 45.2% males). Participants' dietary sodium and potassium intakes were determined by 24-hour urinary sodium and potassium excretions. In addition, we estimated their adherence to Mediterranean diet by the use of an 11-item MedDietScore (range 0-55). The mean sodium excretion was 175 (SD 72) mmol/day, equivalent to 4220 (1745) mg of sodium or 10.7 (4.4) g of salt per day, and the potassium excretion was 65 (25) mmol/day, equivalent to 3303 (1247) mg per day. Men had higher sodium and potassium excretions compared to women. Only 5.6% of the sample had salt intake <5 g/day, which is the target intake recommended by the World Health Organization. Mean sodium-to-potassium excretion ratio was 2.82 (1.07). There was no significant difference in salt or potassium intake or their ratio across MedDietScore quartiles. No significant relationships were found between salt intake and adherence to a Mediterranean diet, suggesting that the perception of the health benefits of the Mediterranean diet does not hold when referring to salt consumption. These results suggest the need for a larger, nation-wide survey on salt intake in Greece and underline the importance of continuation of salt reduction initiatives in Greece.

Meta-Analysis of Potassium Intake and the Risk of Stroke

Background

The possibility that lifestyle factors such as diet, specifically potassium intake, may modify the risk of stroke has been suggested by several observational cohort studies, including some recent reports. We performed a systematic review and meta‐analysis of existing studies and assessed the dose–response relation between potassium intake and stroke risk.

Methods and Results

We reviewed the observational cohort studies addressing the relation between potassium intake, and incidence or mortality of total stroke or stroke subtypes published through August 6, 2016. We carried out a meta‐analysis of 16 cohort studies based on the relative risk (RR) of stroke comparing the highest versus lowest intake categories. We also plotted a pooled dose–response curve of RR of stroke according to potassium intake. Analyses were performed with and without adjustment for blood pressure. Relative to the lowest category of potassium intake, the highest category of potassium intake was associated with a 13% reduced risk of stroke (RR=0.87, 95% CI 0.80–0.94) in the blood pressure–adjusted analysis. Summary RRs tended to decrease when original estimates were unadjusted for blood pressure. Analysis for stroke subtypes yielded comparable results. In the spline analysis, the pooled RR was lowest at 90 mmol of potassium daily intake (RRs=0.78, 95% CI 0.70–0.86) in blood pressure–adjusted analysis, and 0.67 (95% CI 0.57–0.78) in unadjusted analysis.

Conclusions

Overall, this dose–response meta‐analysis confirms the inverse association between potassium intake and stroke risk, with potassium intake of 90 mmol (≈3500 mg)/day associated with the lowest risk of stroke.

Potassium Intake, Bioavailability, Hypertension, and Glucose Control

Potassium is an essential nutrient. It is the most abundant cation in intracellular fluid where it plays a key role in maintaining cell function. The gradient of potassium across the cell membrane determines cellular membrane potential, which is maintained in large part by the ubiquitous ion channel the sodium-potassium (Na+-K+) ATPase pump. Approximately 90% of potassium consumed (60–100 mEq) is lost in the urine, with the other 10% excreted in the stool, and a very small amount lost in sweat. Little is known about the bioavailability of potassium, especially from dietary sources. Less is understood on how bioavailability may affect health outcomes. Hypertension (HTN) is the leading cause of cardiovascular disease (CVD) and a major financial burden ($50.6 billion) to the US public health system, and has a significant impact on all-cause morbidity and mortality worldwide. The relationship between increased potassium supplementation and a decrease in HTN is relatively well understood, but the effect of increased potassium intake from dietary sources on blood pressure overall is less clear. In addition, treatment options for hypertensive individuals (e.g., thiazide diuretics) may further compound chronic disease risk via impairments in potassium utilization and glucose control. Understanding potassium bioavailability from various sources may help to reveal how specific compounds and tissues influence potassium movement, and further the understanding of its role in health.