Addition of inulin to breakfast does not acutely affect serum ionized calcium and parathyroid hormone concentrations

Background/Aims: The aim of the present study was to investigate the effect s of inulin on calcium metabolism. The study consisted of two separate part s both of which had a randomized two-period cross-over design. Methods: Fif teen young healthy women volunteered to participate in this study. During t he first part of the study, cheese containing 210 mg of calcium, either wit h 15 g of inulin or without any inulin, was ingested at breakfast, and in t he second part, 210 mg of calcium as a supplement, either with 15 g inulin or without inulin, was ingested. The whole day's diet was standardized. Bef ore breakfast, and 2, 4, 6 and 8 h after breakfast, a blood sample was take n, and intact parathyroid hormone (iPTH), ionized calcium (iCa) and total c alcium were measured. Urine was collected throughout the day, and the 8-, 1 2- and 24-hour calcium excretion was calculated. Results: The iPTH or iCa c oncentration curves (AUCs) did not differ over 8 h, whether or not inulin w as consumed at breakfast. The postload urinary calcium excretion was not af fected by the inulin. Conclusion: Fifteen grams of inulin in fresh cheese o r with a calcium supplement (210 mg Ca) taken at breakfast does not acutely affect the markers of calcium metabolism as opposed to a corresponding bre akfast without inulin. Copyright (C) 2000 S. Karger AG, Basel.