Urinary carnitine excretion increases during experimental vitamin C depletion of healthy men

• Published in: The Journal of nutritional biochemistry 1997-05, Vol.8 (5), p.265-269
• Main Authors: Jacob, Robert A., Pianalto, Frederick S.
• Format: Article
• Language: English
• Subjects: ACIDE ASCORBIQUE; ACIDO ASCORBICO; ALIMENTACION; ALIMENTATION; ASCORBIC ACID; Biological and medical sciences; BLOOD PLASMA; CARENCE EN VITAMINE; CARNITINA; CARNITINE; COMPLEMENT ALIMENTAIRE; DEFICIENCIA DE VITAMINAS; DIET; DIETA; DOSAGE EFFECTS; EFECTOS DE DOSIFICACION; EFFET DOSE; ESTADO NUTRICIONAL; ETAT NUTRITIONNEL; EXCRECION; EXCRETION; EXPERIMENTACION; EXPERIMENTATION; FEEDING; Feeding. Feeding behavior; Fundamental and applied biological sciences. Psychology; HOMBRES; HOMME; humans; INGESTION DE NUTRIENTES; INGESTION DE SUBSTANCES NUTRITIVES; LEUCOCITOS; LEUCOCYTE; LEUKOCYTES; MEN; NUTRIENT INTAKE; NUTRITIONAL STATUS; ORINA; PLASMA SANGUIN; PLASMA SANGUINEO; REFEEDING; REGIME ALIMENTAIRE; SUPLEMENTOS; SUPPLEMENTS; TRIGLICERIDOS; TRIGLYCERIDE; TRIGLYCERIDES; URINE; Vertebrates: anatomy and physiology, studies on body, several organs or systems; vitamin C; VITAMIN DEFICIENCIES; VITAMINAS; VITAMINE; VITAMINS
• ISSN: 0955-2863; 1873-4847
• DOI: 10.1016/S0955-2863(97)89663-5

The requirement for ascorbic acid in the biosynthesis of carnitine may provide an explanation for the muscle weakness of scurvy and the basis for a functional measure of ascorbate status. To determine the relationship between vitamin C nutriture and carnitine status in humans, we measured total plasma and urinary carnitine concentrations in samples taken from two vitamin C depletion/repletion studies performed with healthy men on a metabolic unit. Throughout the 13-week studies, the groups of nine and eight men consumed a vitamin C-deficient diet that was supplemented with ascorbic acid to provide varying intakes of the vitamin from 5 to 605 mg/day. The subjects attained a state of moderate, nonscorbutic vitamin C deficiency during periods of low vitamin C intake, as indicated by plasma and leukocyte ascorbate concentrations. Plasma carnitine and triglyceride concentrations were not affected by the various vitamin C intakes; however, urinary carnitine excretion was increased during periods of ascorbate deficiency and was inversely related to leukocyte ascorbate concentrations. Vitamin C deficiency increases carnitine excretion, but the increased carnitine loss has no effect on carnitine status over a period of nearly 9 weeks. Total plasma carnitine is not a useful functional measure of human vitamin C status.