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Randomized Controlled Trial
. 2009 Jan;94(1):96-102.
doi: 10.1210/jc.2008-1662. Epub 2008 Oct 21.

Treatment with potassium bicarbonate lowers calcium excretion and bone resorption in older men and women

Bess Dawson-Hughes  1 , Susan S Harris, Nancy J Palermo, Carmen Castaneda-Sceppa, Helen M Rasmussen, Gerard E Dallal
Affiliations
Randomized Controlled Trial

Treatment with potassium bicarbonate lowers calcium excretion and bone resorption in older men and women

Bess Dawson-Hughes et al. J Clin Endocrinol Metab. 2009 Jan.

Abstract

Context: Bicarbonate has been implicated in bone health in older subjects on acid-producing diets in short-term studies.

Objective: The objective of this study was to determine the effects of potassium bicarbonate and its components on changes in bone resorption and calcium excretion over 3 months in older men and women.

Design, participants, and intervention: In this double-blind, controlled trial, 171 men and women age 50 and older were randomized to receive placebo or 67.5 mmol/d of potassium bicarbonate, sodium bicarbonate, or potassium chloride for 3 months. All subjects received calcium (600 mg of calcium as triphosphate) and 525 IU of vitamin D(3) daily.

Main outcome measures: Twenty-four-hour urinary N-telopeptide and calcium were measured at entry and after 3 months. Changes in these measures were compared across treatment groups in the 162 participants included in the analyses.

Results: Bicarbonate affected the study outcomes, whereas potassium did not; the two bicarbonate groups and the two no bicarbonate groups were therefore combined. Subjects taking bicarbonate had significant reductions in urinary N-telopeptide and calcium excretion, when compared with subjects taking no bicarbonate (both before and after adjustment for baseline laboratory value, sex, and changes in urinary sodium and potassium; P = 0.001 for both, adjusted). Potassium supplementation did not significantly affect N-telopeptide or calcium excretion.

Conclusions: Bicarbonate, but not potassium, had a favorable effect on bone resorption and calcium excretion. This suggests that increasing the alkali content of the diet may attenuate bone loss in healthy older adults.

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Figures

Figure 1
Figure 1
Mean 3-month change in urinary NTX/Cr by treatment group, adjusted for sex and baseline NTX/Cr.
Figure 2
Figure 2
Mean 3-month changes in urinary Ca/Cr, NTX/Cr, and NAE/Cr by HCO3 group, adjusted for sex, baseline value, and 3-month changes in sodium/Cr and K/Cr.
Figure 3
Figure 3
Mean urinary NTX/Cr and Ca/Cr by NAE/Cr tertile at the end of the study, adjusted for sex, baseline value, and for sodium/Cr and K/Cr at the end of the study.
See this image and copyright information in PMC

References

    1. Lemann Jr J 1999 Relationship between urinary calcium and net acid excretion as determined by dietary protein and potassium: a review. Nephron 81(Suppl 1):18–25 - PubMed
    1. Davies DF, Shock NW 1950 Age changes in glomerular filtration rate, effective renal plasma flow, and tubular excretory capacity in adult males. J Clin Invest 29:496–507 - PMC - PubMed
    1. Rowe JW, Andres R, Tobin JD, Norris AH, Shock NW 1976 The effect of age on creatinine clearance in men: a cross-sectional and longitudinal study. J Gerontol 31:155–163 - PubMed
    1. Frassetto L, Sebastian A 1996 Age and systemic acid-base equilibrium: analysis of published data. J Gerontol A Biol Sci Med Sci 51:B91–B99 - PubMed
    1. Bhargava U, Bar-Lev M, Bellows CG, Aubin JE 1988 Ultrastructural analysis of bone nodules formed in vitro by isolated fetal rat calvaria cells. Bone 9:155–163 - PubMed

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