This Article Full Text (PDF) Submit a related Letter to the Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints, Permissions and Rights Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by DAWSON-HUGHES, B. Articles by RASMUSSEN, H. M. Search for Related Content PubMed PubMed Citation Articles by DAWSON-HUGHES, B. Articles by RASMUSSEN, H. M.

Effect of Lowering Dietary Calcium Intake on Fractional Whole Body Calcium Retention^*

Calcium and Bone Metabolism Laboratory, U.S. Department of Agriculture Human Nutrition Research Center on Aging, Tufts University Boston, Massachusetts 02111

Address requests for reprints to: Bess Dawson-Hughes, M.D., Calcium and Bone Metabolism Laboratory, Human Nutrition Research Center on Aging, Tufts University, 711 Washington Street, Boston,

Although fractional calcium absorption is known to vary inversely with calcium intake, the extent and timing of individual hormonal and calcium absorption responses to altered calcium intake have not been defined. We measured fractional whole body retention of orally ingested ⁴⁷Ca, an index of calcium absorption, in nine normal women after they had eaten a 2000-mg calcium diet for 8 weeks and a 300-mg calcium diet for 1, 2, 4, and 8 weeks. After the diet change, serum intact PTH (32.2% increase; P = 0.005), serum 1,25-dihydroxyvitamin D [1,25-(OH)₂D; 43.8% increase; P = 0.003], and fractional whole body calcium retention (42.8% increase; P = 0.004) increased within 1 week. Although the PTH and calcium retention responses remained fairly constant throughout the low calcium intake period, serum 1,25-(OH)₂D concentrations declined toward baseline after week 1. Thus, the late increase in calcium retention may have resulted from calcium absorption that was independent of 1,25-(OH)₂D stimulation.

^* This work was supported by the USDA Human Nutrition Research Center on Aging at Tufts University and USPHS Grant GER 1R03-AG-05821-01.

Received November 17, 1987.

This article has been cited by other articles:

				H. A Bischoff-Ferrari, E. Giovannucci, W. C Willett, T. Dietrich, and B. Dawson-Hughes Estimation of optimal serum concentrations of 25-hydroxyvitamin D for multiple health outcomes Am. J. Clinical Nutrition, July 1, 2006; 84(1): 18 - 28. [Abstract] [Full Text] [PDF]

				W. W. Campbell, J. C. Fleet, R. T. Hall, and N. S. Carnell Short-Term Low-Protein Intake Does Not Increase Serum Parathyroid Hormone Concentration in Humans J. Nutr., August 1, 2004; 134(8): 1900 - 1904. [Abstract] [Full Text] [PDF]

				R. P. Heaney Excess Dietary Protein May Not Adversely Affect Bone J. Nutr., June 1, 1998; 128(6): 1054 - 1057. [Abstract] [Full Text]