Format

Send to

Choose Destination
Am J Clin Nutr. 2012 Jun;95(6):1487-94. doi: 10.3945/ajcn.111.032045. Epub 2012 May 2.

Effect of soy isoflavone supplementation on nitric oxide metabolism and blood pressure in menopausal women.

Author information

1
U.S. Department of Agriculture/Agricultural Research Service, Children's Nutrition Research Center, Baylor College of Medicine, Houston, TX 77030, USA. wwong@bcm.edu

Abstract

BACKGROUND:

Isoflavones, having chemical structures similar to estrogens, are believed to stimulate nitric oxide production and thus lower blood pressure. The efficacy of soy isoflavone supplementation to stimulate nitric oxide production and lower blood pressure in menopausal women with high normal blood pressure remains unknown.

OBJECTIVE:

The objective was to test the effect of soy isoflavone supplementation on nitric oxide production and blood pressure in menopausal women with high normal blood pressure.

DESIGN:

A randomized, double-blind, parallel, placebo-controlled 6-wk trial was conducted to assess the effects of daily supplementation with 80 mg soy hypocotyl isoflavones (in aglycone units) on nitric oxide metabolism and blood pressure in 24 menopausal women with 12 women per group. Changes in nitric oxide metabolism were assessed via a primed, constant-infusion protocol with [15N]arginine and [13C]- and [2H]citrulline. Changes in blood pressure and associated vascular hemodynamics were assessed via office and 24-h ambulatory blood pressure monitoring, forearm blood flow, and indexes of arterial compliance.

RESULTS:

When compared with placebo and after control for pretreatment values, soy isoflavone supplementation had no effect on arginine flux, citrulline flux, nitric oxide synthesis, blood pressure, forearm blood flow, or estimates of arterial stiffness.

CONCLUSION:

Daily supplementation with 80 mg soy hypocotyl isoflavones over a 6-wk period had no effect on nitric oxide metabolism or blood pressure and associated vascular hemodynamics in menopausal women with high normal blood pressure.

PMID:
22552034
PMCID:
PMC3349458
DOI:
10.3945/ajcn.111.032045
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Silverchair Information Systems Icon for PubMed Central
Loading ...
Support Center