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BMC Musculoskeletal Disorders
Published in: BMC Musculoskeletal Disorders 1/2010

Open Access 01-12-2010 | Research article

Low urine pH and acid excretion do not predict bone fractures or the loss of bone mineral density: a prospective cohort study

Authors: Tanis R Fenton, Misha Eliasziw, Suzanne C Tough, Andrew W Lyon, Jacques P Brown, David A Hanley

Published in: BMC Musculoskeletal Disorders | Issue 1/2010

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Abstract

Background

The acid-ash hypothesis, the alkaline diet, and related products are marketed to the general public. Websites, lay literature, and direct mail marketing encourage people to measure their urine pH to assess their health status and their risk of osteoporosis.
The objectives of this study were to determine whether 1) low urine pH, or 2) acid excretion in urine [sulfate + chloride + 1.8x phosphate + organic acids] minus [sodium + potassium + 2x calcium + 2x magnesium mEq] in fasting morning urine predict: a) fragility fractures; and b) five-year change of bone mineral density (BMD) in adults.

Methods

Design: Cohort study: the prospective population-based Canadian Multicentre Osteoporosis Study. Multiple logistic regression was used to examine associations between acid excretion (urine pH and urine acid excretion) in fasting morning with the incidence of fractures (6804 person years). Multiple linear regression was used to examine associations between acid excretion with changes in BMD over 5-years at three sites: lumbar spine, femoral neck, and total hip (n = 651). Potential confounders controlled included: age, gender, family history of osteoporosis, physical activity, smoking, calcium intake, vitamin D status, estrogen status, medications, renal function, urine creatinine, body mass index, and change of body mass index.

Results

There were no associations between either urine pH or acid excretion and either the incidence of fractures or change of BMD after adjustment for confounders.

Conclusion

Urine pH and urine acid excretion do not predict osteoporosis risk.
Appendix
Available only for authorised users
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Metadata
Title
Low urine pH and acid excretion do not predict bone fractures or the loss of bone mineral density: a prospective cohort study
Authors
Tanis R Fenton
Misha Eliasziw
Suzanne C Tough
Andrew W Lyon
Jacques P Brown
David A Hanley
Publication date
01-12-2010
Publisher
BioMed Central
Published in
BMC Musculoskeletal Disorders / Issue 1/2010
Electronic ISSN: 1471-2474
DOI
https://doi.org/10.1186/1471-2474-11-88

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