Table 2.

Nutrient composition of infant formula pretreated with sodium polystyrene sulfonate (SPS) in the Low K protocol

Nutrient (mg/L)	SPS dose in formula (in g/mEq K+)
	Untreated formula (no SPS added)	0.25	0.50	1.0
Suplena®
Nutrients reduced
Calcium	1145±20	1021±43 (−11 %)	954±89 (−17 %)*	706±53 (−38 %)***
Copper	2.1±0.1	2.1±0.1(−3%)	2.1±0.1(−3%)	1.9±0(−11 %)**
Manganese	2.4±0.1	2.4±0.1(−3%)	2.3±0.1(−7 %)*	2.0±0.1(−16 %)***
Phosphorus	816±20	814±17 (0 %)	830±8(+2 %)	762±9(−7%)**
Potassium	1069±23	976±96 (−9%)	1002±155(−6%)	710±61(−34 %)**
Zinc	31.5±0.6	29.9±0.8(−5%)	28.4±1(−10 %)**	25.1±0.6(−20 %)***
Nutrients increased
Iron	22±0.6	24±0.6(+9 %)**	27±0(+25 %)***	29±0(+34 %)***
Sodium	673±17	1271±68 (+89 %)**	1897±191(+182 %)***	2426±139(+260 %)***
Sulfur	438±9	521±21 (+19 %)	636±76 (+45 %)**	619±38 (+41 %)**
pH [H+]	6.69	6.89***	7.03***	7.19***
Nutrients unaffected
Magnesium	194±4	192±10 (−1 %)	200±19 (+3 %)	182±12 (−6%)
Similac® PM 60/40
Nutrients reduced
Calcium	456±29	420±39 (−8%)	396±73(−13 %)	323±31 (−29 %)*
Copper	0.7±0	0.6±0.1(−19 %)*	0.7±0.1(−5%)	0.6±0(−14 %)
Magnesium	48±0.6	35±2.9(−26 %)**	40±5(−17 %)	46±2(−3%)
Potassium	588±7	395±36 (−33 %)***	338±50 (−42 %)***	218±9(−63 %)***
Nutrients increased
Iron	5±0	6±0.6(+13 %)	8±0.6(+53 %)**	9±0.6(+87 %)***
Sodium	214±3	399±31 (+86 %)***	617±54 (+188 %)***	744±24 (+247 %)***
pH [H+]	7.13	7.53 ***	7.71 ***	7.94 ***
Nutrients unaffected
Phosphorus	206±10	214±18 (+4 %)	221±27 (+7 %)	208±13 (+6 %)
Sulfur	227±3	224±16 (−1 %)	296±95(+31 %)	284±20(+25 %)
Zinc	5.9±0.2	5.4±0.4(−8%)	5.7±0.3(−2%)	5.6±0.2(−4%)

Significant differences were tested with pairwise comparison analysis (Tukey’s Honest Significant Difference) and compared to untreated samples:

^*p≤ 0.05,

^**p≤ 0.01,

^***p≤0.001

Data are given as the mean ± standard deviation (SD), with the percentage change given in parenthesis. Only results from the 30 min treatment times are shown due to non-significant differences being detected between treatment times

SPS, Sodium polystyrene sulfonate