Nutritional Biomarker Analyses for Hypertension-Related Risk Assessment and Control

Abstract

A simple method to collect 24-hour urine (24U) by sampling 2.5% of the voided urine each time was developed for analyzing the biomarkers of the intakes of salt (NaCl), vegetables and grains (K, Mg), soys (isoflavones), sea-foods (taurine), protein (urea nitrogen) etc. This method was applied to WHO-coordinated CARDIAC (Cardiovascular Diseases and Alimentary Comparison) study covering 61 populations in 25 countries, and revealed significant positive associations of Na or Na/K with blood pressure (BP) and stroke mortality and significant inverse associations of isoflavones or taurine with coronary heart disease (CHD) mortality, indicating the adverse effect of salt intake on BP and stroke and beneficial effect of soy or sea food intakes on CHD. Furthermore, higher urinary taurine and/or Mg excretions were associated with significantly lower risks of metabolic syndromes such as obesity, hypertension and hypercholestelomia. 24U collections were useful to prove nutritional improvement by intervention studies for observing soy intake effect on BP and atherogenic index in Japanese immigrants living in Brazil, and in Australian Aboriginals, for observing taurine effect on BP in Tibetans and for confirming soy and fish effects on the risks of metabolic syndromes in Japanese businessmen. 24U collection was utilized for population strategy to reduce salt and to increase soy intake in 5.6 million people of Hyogo Prefecture. A simple method for 24U collection has enabled us to utilize nutritional biomarkers for hypertension-related disease risk analyses, and to apply objective nutritional intake estimation to intervention studies as well as to population strategy for nutritional improvement, and therefore, the methodology will contribute to hypertension-related disease prevention and global health promotion.