Manganese infants

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 Food and Nutrition Board, National Research Council, National Academy of Sciences (A7) has listed safe intake levels of manganese although information was, at the time of the 1980 listing, too fragmentary for exact recommendations to be made. These manganese "safe intake level" listings were as follows 2.5-5.0 mg/day for adults, 0.7-1.0 mg/day for infants and 1.0-5.0 mg/day for toddlers. 

There is a possibility that some milk constituents regulate the absorption of ions in the intestine. In studying manganese metabolism we turned to the low iron content in milk. Iron has received great attention in pediatric nutrition. The concern has been to prevent the anemia caused by iron deficiency earlier often found in childhood. Wide milk consumption by infants and young children makes this food an attractive vehicle for iron fortification. Iron-enriched proprietary milk substitutes can adequately prevent the anemia common to infants who subsist largely on low-iron mother s or cow s milk (53). 

The manganese balance of ten 6-day old breast-fed infants was measured for a 3-day period by Widdowson in 1969 (20). For a 3.5 kg infant, an intake of 7 (ig/day produced a negative balance of 31 ig. Alexander et al. (8) studied the manganese requirements of children, 3 months to 9 years, fed normal and synthetic diets. From calculation of their data, a manganese intake of 1.15 mg/day in a 20 kg child would produce a positive retention of 0.16 mg. 

Official Methods of Analysis of AOAC International, 17th edn. Rev 1, AOAC International, Gaithersburg, MD, USA, Official Method 984.27. Calcium, Copper, Iron, Magnesium, Manganese, Phosphorus, Potassium, Sodium, and Zinc in Infant Formula - Inductively Coupled Plasma Emission Spectroscopic Method (2002)... 

Strange RC, Cotton W, Fryer AA, Jones P, Bell J, Hume R. Lipid peroxidation and expression of copper-zinc and manganese superoxide dismutase in lungs of premature infants with hyaline membrane disease and bronchopulmonary dysplasia. J Lab Clin Med 116 (1990) 666-673. 

Stastny, D., Vngei, R. S-, and Picciano, M, K (1984). Manganese intake and serum manganese concentration of human milk-fed and formula-fed infants. Aw. /. Clin. Duir 39, 872-878,... 

Manganese is a natural component of most foods. The highest manganese concentrations (up to 40 ppm) are found in nuts and grains, with lower levels (up to 4 ppm) found in milk products, meats, fish, and eggs. Concentrations of manganese in infant formulas range from 34 to 1000 ppb, compared to concentrations of 10 ppb in human milk and 30 ppb in cow s milk. 

For infants the UL could not be set because. There is concern about the potential toxicity for infants whose immature hepatic develop-the biliary excretion of excess manganese, only dietary source of manganese in the age months should be from normal diet or from... 

One study showed that, in full-term infants, manganese is absorbed from breast milk and cow s milk formulas that were either unsupplemented or supplemented with iron, copper, zinc, and iodine (Domer et al. 1989). Manganese intake was greater in the formula-fed infants than in the breast-fed infants due to the higher manganese content of the formula. However, breast-fed infants retained more of their daily intake of... 

There is some evidence to suggest that manganese absorption is age-dependent. Dorner et al. (1989) have shown that infants, especially premature infants, retain a higher proportion of manganese than adults. 

Concentrations of manganese in select human and animal tissues are presented in Table 2-6 and concentrations of manganese in plasma and serum in infants of differing ages and adults are presented in Table 2-7. 

The ESADDIs for manganese are as follows 0.3-0.6 mg/day for infants from birth to 6 months ... 

The World Health Organization (WHO 1981) estimated that the typical human exposure level via inhalation for the general population in areas without manganese-emitting industries is <2 pg/day and that in industrial areas it could reach 4-10 pg/day. While data from animals suggest that typical human exposure levels are not of concern to either adults or infants, it must be remembered that animals (with the possible exception of nonhuman primates) do not appear to be as sensitive to manganese as humans, possibly due to pharmacokinetic differences. Thus, there is considerable uncertainty in using data from rodent models to estimate a... 

Manganese is known to cross the placenta and has been detected in cord blood in healthy full-term and preterm infants. It is unknown whether mothers exposed to increased concentrations of manganese will pass on toxic amounts of the metal to their unborn children via the blood. However, as manganese is an essential nutrient and is part of the human body at all times, it is expected to be found in all tissues and fluids of the infant. Manganese is also naturally found in breast milk (typical concentrations in mature milk range from... 

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