Increased metabolic rate in obese women after ingestion of potassium, magnesium- and phosphate-enriched orange juice or injection of ephedrine.

Author: Jaedig S, Henningsen NC

Author affiliation: Department of Medicine, Lund University, Malmo General Hospital, Sweden.

Publication date & source: 1991.06, Int J Obes., 15(6):429-36.

Publication type: Research Support, Non-U.S. Gov't

Thirty-six obese, pre-menopausal women were studied after an overnight fast and randomized to four different regimens of metabolic stimuli: group I (n = 12), 100 ml orange juice with dissolved K- and Mg-phosphates (K, 40 mmol; Mg, 17.5 mmol; HPO4, 35 mmol); group II (n = 8), 100 ml of water with electrolytes as in group I; group III (n = 8), 100 ml of orange juice; group IV (n = 8), injection of ephedrine intravenously, 0.25 mg/kg body weight. The women in groups I, II and III were further stimulated with ephedrine as in group IV and new measurements made. Thirty minutes after the first stimulus VO2, VCO2 and energy expenditure (EE) rose significantly (13.1-16.5 per cent) in groups I and IV only. In groups I and III the blood concentrations of glucose, insulin, and C-peptide rose significantly. After the second stimulus (ephedrine i.v.) no further increase in VO2, VCO2 and EE occurred in group I, but the increases from basal values became significant in group III. In all women at baseline, whole-body potassium was significantly correlated to VO2. Serum-magnesium was negatively correlated to A/I weight (actual/ideal weight). We conclude that the addition of K- and Mg-phosphates to glucose increases the postprandial thermogenesis in obese patients.