Breast milk containing manganese

Manganese is found in much higher concentrations in infant formulas than in breast milk. In fact, soy-based formulas were shown to contain about 80 times more Mn than breast milk [11]. Also, animal protein-based formulas contained also about 30 times more Mn than human milk. Infants are not able to absorb and excrete excess Mn during their first year of life, a period of rapid development. As Mn is neurotoxic and impairs intestinal Fe absorption, it would be desirable to reduce Mn levels in infant formulas down to those found in human milk (4-8 p,g l-1). Coni et al. [12] reported that in formulas more than 25 percent of total Mn is bound to caseins. On the other hand, Mn present in soy- and in cow s milk-based formula whey is mainly associated with LMW components (< 10 kDa), as is the case with human milk whey [15, 18, 34, 72],... 

The upper level of manganese that should be present in infant formula is uncertain, with Hambidge and Krebs [36] proposing an upper limit of 50 p,g/100 kcal (approximately 200 xg/liter) based on toxicity levels however, cow s milk formulas typically contain much more manganese (80-100 xg/liter) than breast milk (6 p.g/liter), and manganese uptake is much greater from the formula [37]. Conclusions here are bedeviled by the fact that the various milks differ not only in... 

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