Human milk, calcium content

A potential concern has been the dietary ratio of calcium to phosphorus (Ca P) in relation to bone health. Based on data from animal studies and on the relative calcium content in bone, a dietary Ca P ratio of 1 1 to 2 1 is recommended as beneficial for bone mineralization in humans (NAS 1980A Chinn 1981 Linkswiler and Zemel 1979). The Ca P ratio in cow s milk (1.3 1) closely approximates that found in bones. The average American diet is estimated to contain a Ca P ratio of 1 1.6 (Chinn 1981 Greger and Krystofiak 1982) to 1 3 (Linkswiler and Zemel 1979), and if no dairy foods are consumed, it may be as low as 1 4. 

UHT processing and storage have no effect on the total calcium content or calcium bioavailability. Calcium, phosphorus, and magnesium are shown to be equally bioavailable to rats from UHT milk, raw milk, and traditionally processed milk (Katz et al. 1981). Also, human infants retain similar amounts of calcium, potassium, and phosphorus whether fed UHT milk or conventionally pasteurized milk (Renner 1980 Mehta 1980). Data to date indicate no significant changes in the nutritional value of UHT milk under controlled heat treatment and subsequent storage. 

It has been stated that idiopathic hypercalcemia has not been known to develop in a wholly breast-fed infant (B6). Morgan et al. (M3), however, have described an infant who was still breast fed at the time of diagnosis at 8 months of age and whose intake of cow s milk consisted only of that present in puddings and other cereal foods. The association between artificial feeding and idiopathic hypercalcemia has been related to the fact that the calcium content of cow s milk is four times that of human milk. On the other hand the phosphorus content of cow s milk is also higher, and this has been suggested as a cause of hypocalcemia in infants (G2). 

Minerals The main mineral constituents in milk are calcium and chlorine, magnesium chloride, phosphate, and citrate. Minerals in milk are mainly present as soluble salts or in colloidal form associated with caseins. Their concentrations may vary enormously. Thus, the minerals present in milk can be classified according to their concentration level as major and minor elements, with small quantitative contributions from trace and ultratrace elements. The total content of minerals in mammalian milks should correspond to the growth requirements of each biological species. Accordingly, the mineral total content in cow milk is four times higher than in human milk. 

According to Lonnerdahl and Glazier (1985), only 1% of the calcium content of human milk and 0.15% of the calcium content of cow milk are bound to a-lactalbumin. Hence, this protein is quantitadvely unimportant for calcium nutridon of the infant. They point out, rather, that the primary role of calcium may be to regulate lactose synthesis and possibly to aid in the secredon of a-lactalbumin. On the other hand, Rao and Brew (1989) have found that Ca(II) is essential for the formation of correct disulfide bonds and the development of nadve conformadon. They suggest that Ca(II) may funcdon to guide the folding of the nascent protein. 

Typically, soymilk contains 8-12% total solids, depending on the water bean ratio used during processing. Protein content is about 3.6% fat, 2.0—3.2% carbohydrates, 2.9—3.9% and ash, -0.5%. The composition of soymilk compares favorably with those of cow s milk and human milk (Chen, 1989). In addition, soymilk is lactose-free and contains higher levels of protein, iron, unsaturated fatty acids, and niacin however, it contains lower amounts of fat, carbohydrates, calcium, riboflavin, thiamine, methionine, and lysine (Kosikowski, 1971). Therefore, many commercial soymilks are fortified with vitamins, minerals, and in some cases, amino acids. The most widely used nutrients for fortifying soymilk are vitamin calcium, and methionine. 

Sea lettuces which draw from the sea contain wealth of mineral elements (Table 5.4). Calcium, one of the most important minerals essential for human body, is accumulated in sea lettuces at a higher level compared with milk, brown rice, spinach, peanuts, and lentils (MacArtain et ah, 2007). Calcium contents in Ulva lactuca, Ulva reticulata, Ulva fasciata were 32.5, 147, and 0.47 mg/100 g edible portion, respectively. Moreover, potassium and sodium are known as electrolytes because their ability to dissociate into positively and negatively charged ions when dissolved in water. Potassium is the major cation of intracellular fluid. Together with sodium, it maintains normal water balance. In addition, potassium also promotes cellular growth and maintains normal blood pressure. Potential source of potassium is Ulva reticulata, which contains 1540 mg potassium per 100 g edible portion (Ratana-arpom and Chirapart, 2006). 

The calcium content of human milk is only about 30 mg per 100 ml, but, provided that the volume produced by the mother is sufficient, the infant s need will be covered. Milk is low in iron but infants accumulate a store of iron during intrauterine life, and this is usually sufficient for the first 4-6 months of independent existence. After this time it is important to supplement the milk diet with iron-containing foods such as strained meat and vegetables. Milk is also relatively deficient in vitamins C and D. The vitamin C content of breast milk is usually adequate, but infants fed on cow s milk may need a supplementary source. Although fresh orange juice and rose hip syrup are good sources, it is undesirable to accustom children to sweet drinks at an early age since later on these can have disastrous effects on the teeth. 

In the UK, it is recommended that infants who are not breast fed are fed modified milks until at least 6 months of age. These contain less solute, protein, sodium, calcium and phosphorus than cows milk. The Codex Alimentarius lays down international standards for infant feeds Some modified milks are based on demineralised whey and milk to reduce the protein content and change the whey casein ratio examples are given in Table 1. This provides an amino acid composition more closely resembling that of human milk but does not overcome the problem that beta-lactoglobulin and other cows milk proteins are introduced and the anti-infective factors provided by human milk are absent. 

Animal origin products such as eggs, milk, fish, red meats and poultry contain low amounts of manganese. Absorption of such minerals as iron, copper, phosphorus and calcium is superior from animals products than from plant-origin foods. As reported by Kies et al. (in this book), manganese apparently is better absorbed by humans from meals containing meat and fish than from those containing plant-protein replacement products. Because of the low content... 

Betapol , a human milkfat substitute produced by Loders Croklaan (Wormerveer, the Netherlands), is produced by interesterification of vegetable oils in which the component TAGs have been modified to more closely resemble those found in breast milk. This product closely mimics the specific structure and fatty acid composition of human milkfat and resembles breast milk in terms of its nutritional value and high content of palmitic acid at the sn-2 position than other milkfat substitutes. In addition, the use of Betapol in infant formula can lead to improved mineral and fat absorption and less calcium soap formation within the intestinal lumen resulting in softer stools. 

CEdcium is the most abundant mineral present in the body. In an adult man, the total content of calcium is about 1-1.5 kg. It is mostly present in bones and teeth in the form of calcium phosphate and calcium carbonate. The concentration of calcium in bones and teeth is 20 mg lOO gm and its concentration in the serum of blood is 9-11 mg/100 ml. Calcium is also present in the soft tissues of body, extra-cellular fluid and plasma. The richest source of calcium is milk and cheese. It is also present in beans, cabbage, turnip, green vegetables, nuts and egg yolk. Adult human being needs about 800 mg calcimn per day while the growing children and pregnant women may need about 1.5 gram per day. 

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