Acid-base conditions regulate calcium and magnesium homeostasis.
BACKGROUND
Previous experimental studies demonstrate that the acid-base balance influences mineral homeostasis by regulating the absorption of calcium and magnesium in the kidneys. No intervention studies are available on population samples.


OBJECTIVE
To study the urinary excretion of calcium and magnesium before and after an intervention with the aim of decreasing the acid load.


METHODS
Healthy subjects aged 50-75 years were recruited by advertising. Urinary calcium, magnesium and urea as well as blood pressure were measured before and after the intervention. This comprised taking tablets containing potassium hydrogen carbonate or potassium chloride (placebo) during 7-10 days.


RESULTS
There were significant relationships between the urinary excretion of urea and magnesium and calcium before the intervention. Comparing before and after intervention, the change in urinary excretion of urea was related to a change in urinary excretion of calcium and magnesium. There was a significant decrease in systolic as well as diastolic blood pressure both after administration of potassium hydrogen carbonate and citrate.


CONCLUSIONS
The results confirm previous studies showing a relation between acid conditions in the body and the excretion of calcium and add new data on magnesium. A blood pressure decrease after potassium has been found in previous studies. This suggests an alternative for the treatment of moderately increased levels of blood pressure that should be further explored.
Rylander
Ragnar
R
BioFact Environmental Health Research Center, Lerum, Sweden. envhealth@biofact.se
Tallheden
Tommi
T
Vormann
Jürgen
J
D000136:Acid-Base Equilibrium; D001639:Bicarbonates / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D002118:Calcium / Q000378:metabolism* / Q000652:urine; D002136:Calcium, Dietary / Q000378:metabolism; D003971:Diastole / Q000187:drug effects / Q000502:physiology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000097:blood / Q000378:metabolism* / Q000652:urine; D011189:Potassium Chloride / Q000494:pharmacology; D017680:Potassium Compounds / Q000494:pharmacology; D013599:Systole / Q000187:drug effects / Q000502:physiology; D014508:Urea / Q000378:metabolism; D014556:Urine / Q000502:physiology
D001639:Bicarbonates; D002136:Calcium, Dietary; D017680:Potassium Compounds; D011189:Potassium Chloride; D014508:Urea; C026329:potassium bicarbonate; D008274:Magnesium; D002118:Calcium