Effect of dose and duration of reduction in dietary sodium on blood pressure levels: systematic review and meta-analysis of randomised trials

Sodium and health-concordance and controversy

Nancy Cook and colleagues describe the sources of agreement and disagreement about the health effects of sodium and how they might be resolved

A Comparison of Strategies to Improve Population Diets: Government Policy versus Education and Advice

Different strategies have been utilized in order to improve the healthiness of the population diet. Many interventions employ education, advice, and encouragement (EAE). Those interventions have been carried out in diverse settings and may achieve modest success; the estimated risk of cardiovascular disease is lowered by about 5–15%. An alternative strategy is action policies carried out by the governments. The removal of trans-fatty acids from food is a model for a successful action policy. Other action policies include requiring a substantial reduction in the amount of salt added to processed foods and ordering schools to cease supplying unhealthy food to students. Taxes and subsidies can be used to increase the price of unhealthy foods, such as sugar-rich foods, and reduce the price of healthy foods, such as fruit and vegetables. It is very probable that action policies are more effective than those based on EAE. They are also much more cost-effective.

The Effects of Two Intervention Strategies to Reduce the Intake of Salt and the Sodium-To-Potassium Ratio on Cardiovascular Risk Factors. A 4-Month Randomised Controlled Study among Healthy Families

The aim was to examine the effects of two different salt reduction strategies on selected cardiovascular risk factors. The study was a four-month cluster randomised controlled study. Eighty-nine healthy Danish families (309 individuals) were randomly assigned to either (A) gradually salt-reduced bread, (B) gradually salt-reduced bread and dietary counselling to further reduce salt intake and increase potassium intake or (C) standard bread (control). The effect was assessed using linear mixed models. Intention to treat analyses comparing changes in the three groups showed a significant reduction in body fat percent (−1.31% (−2.40; −0.23)) and a borderline significant reduction in total plasma cholesterol (−0.25 mmol/L (−0.51; 0.01) and plasma renin (−0.19 pmol/L (−0.39; 0.00) in group A compared to the control group. Adjusted complete case analyses showed a significant reduction in total plasma cholesterol (−0.29 mmol/L (−0.50; −0.08), plasma LDL cholesterol (−0.08 mmol/L (−0.15; −0.00)), plasma renin (−0.23 pmol/L (−0.41; −0.05)), plasma adrenaline (−0.03 nmol/L (−0.06; −0.01)) and body fat percent (−1.53% (−2.51; −0.54)) in group A compared to the control group. No significant changes were found in group B compared to the control group. In conclusion, receiving sodium reduce bread was associated with beneficial changes in cardiovascular risk factors. No adverse effects were observed.

Critical review of nutrition, blood pressure and risk of hypertension through the lifecycle: do B vitamins play a role?

Hypertension is the leading cause of preventable mortality worldwide, contributing to over 9 million deaths per annum, predominantly owing to cardiovascular disease. The association of obesity, physical inactivity and alcohol with elevated blood pressure (BP) is firmly established. Weight loss or other dietary strategies, such as the Dietary Approaches to Stop Hypertension (DASH) diet, have been shown to be effective in lowering BP. Additionally, specific nutrients are recognised to contribute to BP, with higher sodium intake linked with an increased risk of hypertension, while potassium is associated with a reduced risk of hypertension. Of note, emerging evidence has identified a novel role for one-carbon metabolism and the related B vitamins, particularly riboflavin, in BP. Specifically in adults genetically at risk of developing hypertension, owing to the common C677T polymorphism in MTHFR, supplemental riboflavin (co-factor for MTHFR) was shown in randomised trials to lower systolic BP by up to 13 mmHg. A BP response to intervention of this magnitude could have important clinical impacts, given that a reduction in systolic BP of 10 mmHg is estimated to decrease stroke risk by 40%. This review aims to explore the factors contributing to hypertension across the lifecycle and to critically evaluate the evidence supporting a role for nutrition, particularly folate-related B vitamins, in BP and risk of hypertension. In addition, gaps in our current knowledge that warrant future research in this area, will be identified.

Dairy Consumption in Relation to Hypertension Among a Large Population of University Students: The MEPHASOUS Study

BACKGROUND

Hypertension is a chronic condition that its prevalence is increasing at an alarming rate. Findings on the association between dairy consumption and hypertension are conflicting and few data are available in the Middle East.

AIM

To assess the association between dairy consumption and hypertension among a large population of university students.

MATERIALS AND METHODS

The current study was performed in the framework of the Mental and Physical Health Assessment of University Student (MEPHASOUS) project. Overall, 67,011 university students with complete information were included in the statistical analysis. To assess dairy consumption, a self-administered dietary habits questionnaire was employed. Blood pressure was measured using a standard protocol. The systolic/diastolic blood pressure of ≥140/90 mmHg was considered hypertension.

RESULTS

Hypertension was prevalent among 6.9% of students. A significant inverse association was found between dairy consumption and the odds of hypertension; such that after taking potential confounders into account, individuals in the highest levels of dairy consumption had 85% lower odds for having hypertension compared with those in the lowest levels (odds ratio (OR): 0.15, 95% confidence interval (CI): 0.13-0.18). Such an inverse association was also seen among males (OR: 0.14, 95% CI: 0.11-0.18) and females (OR: 0.16, 95% CI: 0.12-0.21), normal-weight students (OR: 0.15, 95% CI: 0.12-0.18) and those with overweight or obesity (OR: 0.15, 95% CI: 0.11-0.21), and individuals with (OR: 0.13, 95% CI: 0.11-0.16) and without (OR: 0.24, 95% CI: 0.17-0.35) family history of hypertension.

CONCLUSION

Our results support the previous findings on the inverse association between dairy consumption and hypertension among university students.