title: Vitamin C restores blood pressure and vasodilator response during mental stress in obese children.
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).
  
  
  CONCLUSIONS
  VitC supplementation reduced the MBP and restored peripheral vasodilatation response during mental stress in obese children.
authors.affiliation: Universidade Federal da Paraíba, João Pessoa, PB, Brazil.
authors.forename: Pricilla Regina Oliveira Fernandes
authors.initials: PR
authors.lastname: Fernandes
authors.forename: Fabio Alexandre dos Santos
authors.initials: FA
authors.lastname: Lira
authors.forename: Vanessa Vieira Lopes
authors.initials: VV
authors.lastname: Borba
authors.forename: Maria José Carvalho
authors.initials: MJ
authors.lastname: Costa
authors.forename: Ivani Credidio
authors.initials: IC
authors.lastname: Trombeta
authors.forename: Maria do Socorro Brasileiro
authors.initials: Mdo S
authors.lastname: Santos
authors.forename: Amilton da Cruz
authors.initials: Ada C
authors.lastname: Santos
mesh_terms: D001205:Ascorbic Acid / Q000008:administration & dosage*; D001794:Blood Pressure / Q000187:drug effects*; D002648:Child; D004311:Double-Blind Method; D005260:Female; D005542:Forearm / Q000098:blood supply*; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D009765:Obesity / Q000188:drug therapy* / Q000378:metabolism; D011446:Prospective Studies; D013315:Stress, Psychological / Q000378:metabolism*; D014664:Vasodilation / Q000187:drug effects*
chemical_list: D001205:Ascorbic Acid