We found a match
Your institution may have rights to this item. Sign in to continue.
- Title
Effects of a ‘healthy’ diet and of acute and long-term vitamin C on vascular function in healthy older subjects
- Authors
Singh, Nivedita; Graves, Jonathan; Taylor, Paul D.; MacAllister, Raymond J.; Singer, Donald R.J.
- Abstract
<B>Objective:</B> Aging is associated with endothelial dysfunction. We studied the acute and longer-term effects of vitamin C compared to a ‘Mediterranean-type’ diet on endothelial function in healthy older subjects. <B>Methods:</B> Bilateral venous occlusion plethysmography was used to measure forearm blood flow in subjects aged 57–80 years. Responses to cumulative intra-arterial doses of the endothelium-dependent dilator bradykinin (BK; n=56; 20, 40, 80 pmol/min) and the nitric oxide donor glyceryl trinitrate (GTN; n=54; 4, 8, 16 nmol/min), were determined alone and in the presence of vitamin C (25 mg/min). We then randomised 54 subjects to a ‘healthy’ diet (n=18), vitamin C (1 g/day; n=18) or placebo for 6 weeks and reassessed endothelial and smooth muscle function. <B>Results:</B> Acute intra-arterial vitamin C did not alter dilatation to BK or GTN. Similar increases in plasma vitamin C occurred on oral vitamin C (83±4 to135±8 μmol/l) and ‘healthy’ diet (84±5 to135±27 μmol/l; P<0.01 for both), with no change seen on placebo. Treatment with a ‘healthy’ diet but not oral vitamin C improved endothelium-dependent (P=0.043) and endothelium-independent dilatation (P=0.011). <B>Conclusions:</B> A ‘Mediterranean-type’ diet rich in vitamin C improves vascular function. Neither acute intra-arterial nor sustained administration of oral vitamin C improves vascular function in healthy older subjects.
- Subjects
AGING; ENDOTHELINS; VITAMIN C
- Publication
Cardiovascular Research, 2002, Vol 56, Issue 1, p118
- ISSN
0008-6363
- Publication type
Article
- DOI
10.1016/S0008-6363(02)00514-X