Phosphate decreases urine calcium and increases calcium balance: A meta-analysis of the osteoporosis acid-ash diet hypothesis

Table 2 Study arm calcium intakes, phosphate doses, urine calcium and calcium balance

Study	n	Phosphate dose (mmol/day)	Phosphate source	Calcium Intake (mmol/day)	Days on Calcium intake*	Days on each balance study after adaption**	Change uCalcium (mmol/day)	Change Calcium balance (mmol/day)
Patton [21]	18	10	Na₂HPO₄ & Na glycerophosphate	9	7	7	-0.4	-0.2
Patton [21]	18	19	"	9	7	7	-1.0	0.6
Patton [21]	18	10	"	24	7	7	-0.4	-0.6
Patton [21]	18	19	"	24	7	7	-1.5	0.3
Patton [21]	18	10	"	39	7	7	-1.0	0.03
Patton [21]	18	19	"	39	7	7	-0.4	1.1
Malm [27]	4	24	H₃PO₄	-	98	7	-0.9	n/a
Malm [27]	2	32	H₃PO₄	11	98	28	-0.7	0.7
Malm [27]	4	26	H₃PO₄	20	98	28	-0.9	0.1
Malm [27]	2	19	H₃PO₄	13	56	56	-1	0.03
Goldsmith [28]	7(4)	32	K₂H & KH₂	21	7	4	-0.9	0.45
Bell [29]	5	37	Na PolyP	18	6	22	-1.7	n/a
Spencer [30]	10	37	Naglycerophosphate	5	0	22	-0.8	0.03
Spencer [30]	8	37	Naglycerophosphate	21	0	40	-1.7	0.70
Spencer [30]	3	39	Naglycerophosphate	36	0	34	-2.3	-0.35
Spencer [30]	6	36	Naglycerophosphate	50	0	31	-2.1	0.10
Hegsted [31]	8	49	KH+PO+	13	0	12	-2.5	0.94
Zemel [32]	8	32	KH₂PO₄	10	2	11	-2.0	2.7
Zemel [32]	8	32	(NaPO₃)₆	10	2	11	-2.0	1.3
Schuette [33]	8	25	KH₂PO₄	15	2	6	-0.9	0.03
Spencer [34]	1	35	Naglycerophosphate	6	0	66	-3.2	0.5
Spencer [34]	4	34	Naglycerophosphate	20	0	42	-3.0	1.3
Spencer [34]	2	41	Naglycerophosphate	34	0	33	-3.6	0.00
Spencer [34]	3	40	Naglycerophosphate	51	0	40	-3.5	0.2
Whybro [36]	9	32	NaH₂PO₄	25	5	2	-1.1	n/a
Whybro [36]	11	48	Not stated	25	5	9	-2.4	n/a
Kemi [37]	14	8	Na₂ Na₃ HPO₄	6	0	1	-0.2	n/a
Kemi [37]	14	24	Na₂ Na₃ HPO₄	6	0	1	-0.5	n/a
Kemi [37]	14	48	Na₂ Na₃ HPO₄	6	0	1	-0.5	n/a
Krapf [35]	6	9.6	IV PO4 vs Cl	35	4	3	-3.5	n/a

* days on calcium intake prior to the measurement of outcomes
** the shortest number of days on the balance study is reported if it varied within the comparison interventions

ISSN: 1475-2891