Ca, P, Mg, Zn, Cu, Mn, Na, K, and Cl contents of infant formulas manufactured in the United States

Abstract

One hundred thirty-five infant formula samples from four manufacturers were assayed for elemental composition during 1981–1985. Product types consisted of ready-to-feed (60), concentrates (47), and powders (28), prepared with milk-base (78) or soy-base (57). Mean elemental levels ± SD per 100 kcal were 85 ± 18 mg Ca, 60 ± 11 mg P, 11 ± 3 mg Mg, 0.9 ± 0.3 mg Zn, 110 ± 32 μg Cu, 87 ± 89 μg Mn, 38 ± 11 mg Na, 120 ± 21 mg K, and 66 ± 8 mg Cl. Mean values for iron (77 samples) that were previously reported are updated to include data for 135 samples. Soy-based formulas had significantly higher levels of Ca, P, Mg, Cu, Mn, Na, and K (α = 0.05). Elemental levels of formulas produced by different firms were significantly different (α = 0.05). Mean levels as percentage of label declaration were 106 (Ca), 104 (P), 133 (Mg), 137 (Fe), 132 (Zn), 136 (Cu), 166 (Mn), 106 (Na), It 6 (K), and 105 (Cl). The mean Ca P ratios were 1.4 for milk-based and 1.5 for soy-based formulas. All products met requirements of the 1980 Infant Formula Act except for two samples that had Cu levels lower than Act specifications.