Ca/P balance

[Sarah Ralston <ralston@AESOP.RUTGERS.EDU>]

Dear Duncan,

Thanks for setting the record straight on the uselessness of blood
samples to determine calcium adequacy-I was planning to post a
similar message but you beat me to it! Good job. Blood phosphorus is
pretty unreliable too, though, as you said, if youget blood and urine
they can calculate a "creatinine clearance" ratio that reflects P intake
pretty well. Can't do the same for calcium because urine calcium fluctuates
widely 
over a 24 hour period....

Sarah and Fling (who is still not in shape...)