Effect of diabetic state and related disorders on the urinary excretion of magnesium and zinc in patients.

We examined the urinary excretion of magnesium and zinc in 175 diabetics [19 insulin-dependent (type I) and 156 insulin-independent (type II)] and in 160 control subjects of the same origin by determining the ratio of the concentration of each of these metals to that of creatinine (creat). Electrothermal atomic absorption spectrophotometry was used for analyzing Mg and Zn in urine. There was no significant difference in the urinary excretion of Mg between the control group [mean (SEM) = 362.6 (15.1) mmole of Mg/mole of creat] and the overall [350.2 (15.7) mmole Mg/mole creat], type I [368.4 (45.0) mmole Mg/mole creat], or type II [347.9 (16.7) mmole Mg/mole creat] diabetics regardless of the disorders associated with diabetes (cardiovascular diseases, neuropathy, retinopathy, infections, and hepatic disease). In contrast, diabetics of both types [2.67 (0.14) mmole Zn/mole creat] with or without a diabetes associated disorder excreted significantly (p = 0.031 to 0.0000) more Zn than did the control subjects [1.76 (0.09) mmole Zn/mole creat]. There was positive correlation between hemoglobin A1c and urinary loss of Mg (p = 0.013) or Zn (p = 0.0241) in patients with type II diabetes. From these data, it appears that of the two elements examined only Zn is associated with higher urinary loss in diabetic state. The discrepancy between our results and those of previous studies for Mg may be ascribed to dissimilarities in the diet habits and metabolism of Mg among diabetics of different geographical origins.