INTRODUCTION Bocker1 in 1853 and Neubauer2 in 1856 reported that diabetic patients excreted more lime salts in their urine than normal individuals. In 1889 Toralbo3 came to a similar conclusion from his findings. Since that time many observations have been recorded, and the conclusion has been reached that diabetics suffer from a loss of calcium from their body. Some of these studies we shall review in detail. Von Moraczewski4 in 1897 found in one case of diabetes mellitus, on a mixed diet, a retention of nitrogen and chlorin coincident with a loss of calcium and phosphorus, the phosphorus loss being nearly three times as great as the calcium loss. The phosphorus loss was 32 per cent. of the intake and the calcium loss 11 per cent. of the intake. On an animal diet containing much less chlorin and lime, and somewhat less phosphorus, the nitrogen balance