Cardiovascular health: relevance of vascular-function markers
From industrial, academic and public health perspectives there is an urgent need to substantiate the validity and relevance of diet-sensitive vascular-function (VF) markers of cardiovascular health (CVH). The aim of this project was to study how, and to what extent, diet-induced changes in VF markers predict CVH outcomes in humans. These questions were addressed via a multidisciplinary approach aimed at demonstrating and unravelling the mechanistic cause-effect relationships between selected dietary components, VF markers, endothelial (dys)function, blood pressure, organ (dys)function, disease risk and other established cardiovascular risk factors.
With financial support from DSM and FrieslandCampina, an additional project was funded to examine, in humans, the relationship between (and underlying mechanisms of) urinary-sulphate excretions and vascular risk. Subjects were provided with a relatively low-sodium, low-potassium diet, for 1 week. The diet contained 2.4g of sodium and 2.3g of potassium per day in a 2,500 kcal intake. Subsequently, while remaining on the study diet, subjects received, randomly over a 4-week period, capsules with either supplemental sodium (3g per day), supplemental potassium (2.8g per day) or a placebo.
In a randomised, placebo-controlled, crossover study with 37 untreated (pre)hypertensive subjects, it was clearly demonstrated that doubling the intake of sodium strongly raised blood pressure, while potassium had a beneficial effect. Arterial stiffness did not change during the 4-week intervention period.
A prospective cohort study of normotensive subjects demonstrated that low urinary potassium excretion was associated with an increased risk of developing hypertension. Such a relationship was not found between the urinary sodium to potassium ratio.
A longer-term human intervention study (6 months) investigating the effects of magnesium supplementation on arterial stiffness has begun in 2014. Furthermore, the International Working Group (experts in the field of VF measurements) combined data from various studies to identify quality standards for measuring flow-mediated dilation.