Submitted to: International Society For Trace Elements Research In Humans
Publication Type: Abstract Only
Publication Acceptance Date: September 1, 1995
Publication Date: N/A
Technical Abstract: In three experiments conducted with postmenopausal women, dietary magnesium was 105 mg/day for 78 days in the first, 115 mg/day for 42 days in the second, and 105 mg/day for 72 days in the third. The diets were similar in all three experiments except dietary copper was about 1.5 mg/day in experiment 1, 1.7 mg/day in experiment 2, and 2.4 mg/day in experiment 3. Variables examined during magnesium depletion were compared to measurements made when the volunteers were consuming a 200 mg/day magnesium supplement for 57 days in experiment 1, 42 days in experiment 2, and 72 days in experiment 3. Urinary excretion of calcium and phosphorus was lowest in experiment one where dietary copper was lowest. Also in experiment one, magnesium supplementation decreased copper balance such that it suggested that less than 1.5 mg of copper a day was inadequate when dietary magnesium was over 300 mg/day. Other changes that may have been caused by a magnesium-enhanced, low copper status were increased erythrocyte superoxide dismutase and serum mid-molecule parathyroid hormone concentrations. In all three experiments, the magnesium deprivation decreased the urinary excretion of magnesium, induced non- positive magnesium balance, decreased the percent of dietary phosphorus found in the feces, and increased calcium balance. In experiments 2 and 3, the amount of calcium in urine was increased by magnesium repletion. In all three experiments, serum cholesterol was higher during magnesium repletion than depletion; the most marked effect was found when dietary copper was the lowest. The findings suggest a relationship between copper and magnesium that can affect variables used in assessing risk to cardiovascular and bone disease.