The Serum Calcium Response to Ingested Calcium

Numerous studies have been made upon the serum calcium response following the ingestion of various calcium compounds.Kahn and Roe (1) reported large rises (80 per cent) in serum calcium following ingestion of 5 to 20 gm. of calcium lactate by fasting subjects.Bauer and Ropes (2) were unable to obtain such large rises, using 5 and 10 gm.doses of calcium lactate in normal human beings; they obtained an average maximal elevation of 8 per cent for the smaller dose and 14 per cent for the larger one. Liebermann(3) studied the absorption of calcium gluconate in human beings and found that 10 gm.doses produced an average maximal elevation of whole blood calcium in ten subjects from an original level around 12 mg.to 16.2 mg. of CaO per 100 cc.Greenberg and Gunther (4) studied the influence of calcium lactate, gluconate, chloride, and acetate upon the serum calcium level of dogs.They concluded that these salts were all equally efficacious in raising the serum calcium and that the magnitude of elevation was proportional to the dosage of calcium.They do not state the definite dosage per kilo of body weight used in obtaining these data.The present study, involving approximately 700 calcium determinations, was made upon normal adult persons and dogs and the study was primarily intended to answer two questions: (1) What effect, if any, does the daily ingestion of considerable doses of calcium have upon the serum calcium response to a given dose of calcium?(2) What is the relationship between serum calcium response and the dosage of calcium?Calcium chloride, gluconate, and lactate were used, and some comparative data were obtained on these salts.