Daily magnesium supplements improve glucose handling in elderly subjects

• Published in: The American journal of clinical nutrition Vol. 55; no. 6; pp. 1161 - 1167
• Main Authors: Paolisso, G, Sgambato, S, Gambardella, A, Pizza, G, Tesauro, P, Varricchio, M, D'Onofrio, F
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Elsevier Inc 01.06.1992; American Society for Clinical Nutrition
• Subjects: ACIDE LACTIQUE; ACIDO LACTICO; administration & dosage; Adult; Aged; Aged, 80 and over; analysis; Biological and medical sciences; blood; blood glucose; Blood Glucose - analysis; Blood Glucose - metabolism; blood plasma; Blood Viscosity; Body Mass Index; c-peptide; C-Peptide - blood; carbohydrate metabolism; Carbohydrates; cell membranes; chemistry; dietary mineral supplements; Double-Blind Method; elderly; ERITROCITOS; ERYTHROCYTE; erythrocytes; Erythrocytes - chemistry; Erythrocytes - physiology; Female; Fundamental and applied biological sciences. Psychology; GLICEMIA; GLUCAGON; Glucagon - blood; glucose disappearance rate; glucose homeostasis; GLYCEMIE; hepatic glucose output; Homeostasis; Humans; Insulin; Insulin - blood; Insulin Resistance; Insulin Resistance - physiology; INSULINA; INSULINE; Lactates; Lactates - blood; lactic acid; MAGNESIO; MAGNESIUM; Magnesium - administration & dosage; Magnesium - blood; Magnesium - urine; Male; MEMBRANAS CELULARES; MEMBRANE CELLULAIRE; membrane microviscosity; metabolism; METABOLISME DES GLUCIDES; METABOLISMO DE CARBOHIDRATOS; Metabolisms and neurohumoral controls; MINERALES; MINERAUX; PEPTIDE; PEPTIDOS; PERSONNE AGEE; physiology; plasma lactate; PLASMA SANGUIN; PLASMA SANGUINEO; Pyruvates; Pyruvates - blood; TERCERA EDAD; urine; Vertebrates: anatomy and physiology, studies on body, several organs or systems; VISCOSIDAD; VISCOSITE; viscosity; glucose homeostasis; plasma lactate; Magnesium; hepatic glucose output; glucose disappearance rate; membrane microviscosity; Human; Oligoelement; Carbohydrate; Glucose; Metabolism; Elderly
• ISSN: 0002-9165; 1938-3207
• DOI: 10.1093/ajcn/55.6.1161

We demonstrated similar plasma concentrations and urinary losses but lower erythrocyte magnesium concentrations (2.18 ± 0.04 vs 1.86 ± 0.03 mmol/L, P < 0.01) in twelve aged (77.8 ± 2.1 y) vs 25 young (36.1 ± 0.4 y), nonobese subjects. Subsequently, aged subjects were enrolled in a double-blind, randomized, crossover study in which placebo (for 4 wk) and chronic magnesium administration (CMA) (4.5 g/d for 4 wk) were provided. At the end of each treatment period an intravenous glucose tolerance test (0.33 g/kg body wt) and a euglycemic glucose clamp with simultaneous [D-3H]glucose infusion and indirect calorimetry were performed. CMA vs placebo significantly increased erythrocyte magnesium concentration and improved insulin response and action. Net increase in erythrocyte magnesium significantly and positively correlated with the decrease in erythrocyte membrane microviscosity and with the net increase in both insulin secretion and action. In aged patients, correction of a low erythrocyte magnesium concentration may allow an improvement of glucose handling.