Vitamin C Restores Blood Pressure and Vasodilator Response During Mental Stress in Obese Children

Arq Bras Cardiol. 2011 Jun;96(6):490-7. doi: 10.1590/s0066-782x2011005000057. Epub 2011 May 6.
[Article in English, Portuguese, Spanish]

Abstract

Background: Peripheral vasodilation response plays an important role in the pathophysiology of obesity and heart disease.

Objective: To evaluate the chronic effect of vitamin C (VitC) supplementation on blood pressure and on vasodilation response to mental stress.

Methods: In a double-blind, randomized and prospective study we evaluated obese children with 8 to 12 years in 2 similar groups: 1) supplemented with 500 mg VitC (n = 11) and 2) placebo (n = 10) for 45 days. Eight age-matched lean control children were also studied. We evaluated: mean blood pressure (MBP), heart rate (HR) and forearm blood flow by venous occlusion plethismography. Forearm vascular conductance (FVC) was calculated by: (forearm blood flow/PAM) X100.

Results: On pre-intervention evaluations obese children showed higher MBP and lower FVC compared to lean control children. After intervention VitC diminished MBP at rest (81 ± 2 vs 75 ± 1 mmHg, p = 0.01), whereas placebo did not promote changes in MBP (p = 0.58). In addition, VitC promoted FVC increase at rest (3.40 ± 0.5 vs 5.09 ± 0.6 un, p = 0.04) and during the mental stress (3.92 ± 0.5 vs 6.68 ± 0.9 un, p = 0.03). Moreover, after VitC supplementation FVC levels were similar to the lean control children at rest (5.09 ± 0.6 vs 5.82 ± 0.4 un, p > 0.05) and during mental stress (6.68 ± 0.9 vs 7.35 ± 0.5 un, p > 0.05).

Conclusion: VitC supplementation reduced the MBP and restored peripheral vasodilatation response during mental stress in obese children.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Ascorbic Acid / administration & dosage*
  • Blood Pressure / drug effects*
  • Child
  • Double-Blind Method
  • Female
  • Forearm / blood supply*
  • Heart Rate / drug effects
  • Humans
  • Male
  • Obesity / drug therapy*
  • Obesity / metabolism
  • Prospective Studies
  • Stress, Psychological / metabolism*
  • Vasodilation / drug effects*

Substances

  • Ascorbic Acid