Inverse Relation of Dietary Protein Markers With Blood Pressure
- 1 October 1996
- journal article
- research article
- Published by Ovid Technologies (Wolters Kluwer Health) in Circulation
- Vol. 94 (7), 1629-1634
- https://doi.org/10.1161/01.cir.94.7.1629
Abstract
Background The purpose of this study was to assess relations to blood pressure (BP) in individuals of markers of dietary protein in their 24-hour urine collections. Methods and Results INTERSALT (INTERnational study of SALT and blood pressure) was a cross-sectional study of 10 020 men and women aged 20 to 59 years in 52 population-based samples in 32 countries worldwide, with quality-controlled standardized procedures and assessment of multiple possible confounders. Three measurements of dietary protein in 24-hour urine of each individual participant were studied: total nitrogen and urea as indexes of total protein intake, and sulfate as an index of sulfur-containing dietary amino acids. Repeat examination was performed in a random 8% of participants to assess reliability and to correct for regression-dilution bias. Significant independent inverse relationships were found between BP (systolic and diastolic) and both 24-hour urinary total nitrogen and urea nitrogen, with adjustment for age, sex, alcohol intake, body mass, and 24-hour urinary sodium, potassium, calcium, and magnesium. With adjustment for regression-dilution bias, it was estimated that systolic and diastolic BP were on average 3.0 and 2.5 mm Hg lower, respectively, for persons with dietary total protein intake 30% above the overall mean than for those whose dietary protein intake was 30% below the overall mean (12.94 versus 6.96 g/d urinary total nitrogen, equivalent to 81 versus 44 g/d dietary protein, respectively). For the association of these markers with diastolic BP, results were similar for younger (20- to 39-year-old) and older (40- to 59-year-old) persons and for women and men. For their relation to systolic BP, regression coefficients were larger both for those aged 40 to 59 years than for those aged 20 to 39 years and for women than for men. Nonsignificant inverse relations were recorded for urinary sulfate and BP. Conclusions These INTERSALT findings lend support to the hypothesis that higher dietary protein intake has favorable influences on BP.This publication has 22 references indexed in Scilit:
- The INTERSALT Study: background, methods, findings, and implicationsThe American Journal of Clinical Nutrition, 1997
- Intersalt revisited: further analyses of 24 hour sodium excretion and blood pressure within and across populationsBMJ, 1996
- Urinary Electrolyte Excretion in 24 Hours and Blood Pressure in the INTERSALT StudyAmerican Journal of Epidemiology, 1994
- Urinary Electrolyte Excretion in 24 Hours and Blood Pressure in the INTERSALT StudyAmerican Journal of Epidemiology, 1994
- The use of 24-h urine samples and energy expenditure to validate dietary assessmentsThe American Journal of Clinical Nutrition, 1994
- INTERSALT study findings. Public health and medical care implications.Hypertension, 1989
- Intersalt: an international study of electrolyte excretion and blood pressure. Results for 24 hour urinary sodium and potassium excretion. Intersalt Cooperative Research Group.BMJ, 1988
- Toward prospective registration of clinical trialsControlled Clinical Trials, 1988
- Urine nitrogen as an independent validatory measure of dietary intake: a study of nitrogen balance in individuals consuming their normal dietThe American Journal of Clinical Nutrition, 1985
- Urinary nitrogen output as a validity test in dietary surveysThe American Journal of Clinical Nutrition, 1980