Vince
Super Moderator
Current evidence suggests that the consumption of low calcium- diets is associated with a higher overall risk for the development of calcium oxalate kidney stones than the consumption of too much calcium.(Parmar, Malvinder S. (2004). "Kidney stones". British Medical Journal 328 (7453): 1420–1424. doi:10.1136/bmj.328.7453.1420. PMID 15191979 )
This is perhaps related to the role of calcium in binding ingested oxalate in the gastrointestinal tract. As the amount of calcium intake decreases, the amount of oxalate available for absorption into the bloodstream increases; this oxalate is then excreted in greater amounts into the urine by the kidneys. In the urine, oxalate is a very strong promoter of calcium oxalate precipitation, about 15 times stronger than calcium.Normal calcium intake is >30mmol/day. There is equivocal evidence that calcium supplements increase the risk of stone formation.
Restricting the intake of food that is high in oxalate is only helpful in those patients who are absorbing excess oxalate ,i.e. a minority of patients as most oxalate excreted in the urine is actually made in the liver.
The formation of calcium phosphate stones can be associated with renal tubular acidosis or hyperparathyroidism.
Some researchers suggested that nanobacteria can cause the formation of kidney stones.(Ciftcioglu N, Bjorklund M, Kuorikoski K, Bergstrom K, Kajander EO. Nanobacteria: an infectious cause for kidney stone formation. Kidney Int 1999;56: 1893-8. [PubMed] )
This is perhaps related to the role of calcium in binding ingested oxalate in the gastrointestinal tract. As the amount of calcium intake decreases, the amount of oxalate available for absorption into the bloodstream increases; this oxalate is then excreted in greater amounts into the urine by the kidneys. In the urine, oxalate is a very strong promoter of calcium oxalate precipitation, about 15 times stronger than calcium.Normal calcium intake is >30mmol/day. There is equivocal evidence that calcium supplements increase the risk of stone formation.
Restricting the intake of food that is high in oxalate is only helpful in those patients who are absorbing excess oxalate ,i.e. a minority of patients as most oxalate excreted in the urine is actually made in the liver.
The formation of calcium phosphate stones can be associated with renal tubular acidosis or hyperparathyroidism.
Some researchers suggested that nanobacteria can cause the formation of kidney stones.(Ciftcioglu N, Bjorklund M, Kuorikoski K, Bergstrom K, Kajander EO. Nanobacteria: an infectious cause for kidney stone formation. Kidney Int 1999;56: 1893-8. [PubMed] )