American Journal of Clinical Nutrition, Vol. 87, No. 1, 193-194,
January 2008
© 2008 American Society for Nutrition
Reply to T Remer
Reina Armamento-Villareal and
Nicola Napoli
Division of Bone and Mineral Diseases
Box 8301
Washington University School of Medicine
660 S Euclid Avenue
St Louis, MO 63110
E-mail: rvillare{at}im.wustl.edu
Dear Sir:
We appreciate the comments of Remer on our article "Effects of dietary calcium compared with calcium supplements on estrogen metabolism and bone mineral density (1)," which was recently published in the Journal. Below are our specific responses to his questions:
- We reexamined the clinical data of our study patients and found that not one of our subjects was taking any form of oral or systemic steroid at the time of the urine collection. Two subjects had a remote history of taking oral steroids, but both stopped taking them within at least 1 y before participating in the study. Thus, the possibility that exogenous steroids influenced the interaction between the adrenal gland and peripheral estrogen production was not a factor in our study.
- Although we included the sum of all the urinary metabolites in our report, it was not our intention to demonstrate the total estrogen production of our subjects. Our purpose was to illustrate that, regardless of total estrogen production, the women who were consuming a significant amount of their calcium from dietary sources had a shift in estrogen metabolism to the active 16
-hydroxyl pathway relative to the women who consumed most of their calcium from supplements.
- We agree with Remer regarding the potential effect of protein or other nutrients on our findings. It is possible that the protein or nutrients, other than calcium, present in dairy products (the main source of dietary calcium in our subjects) may have affected the bone density and urinary estrogen metabolite findings of our patients. In fact, we acknowledged this possibility in our discussion. Finally, because we did not assess the individual protein intake of our subjects, the issue of whether the amount of protein in our patient's diets may have influenced our bone density findings remains undetermined. We hope that these answers have satisfactorily addressed Remer's comments.
ACKNOWLEDGMENTS
Neither author had a conflict of interest to declare.
REFERENCE
- Napoli N, Thompson J, Civitelli R, Armamento-Villareal RC. Effects of dietary calcium compared with calcium supplements on estrogen metabolism and bone mineral density. Am J Clin Nutr 2007;85:1428–33.[Abstract/Free Full Text]
