Vitamin E, lipid fractions, and fatty acid composition of colostrum, transitional milk, and mature milk: an international comparative study

Abstract

Triglycerides, cholesterol, fatty acid composition, and tocopherols were determined in colostrum, transitional milk, and mature milk in St Lucia. With progress of lactation, triglycerides and percentage medium-chain fatty acids increased whereas tocopherols, cholesterol, and percentage long-chain polyunsaturated fatty acids decreased. These changes reflect augmented de novo synthesis of fatty acids (8:0, 10:0, 12:0, and 14:0) in the mammary gland and a tendency of increasing fat-globule size as milk matures. Transitional and mature milks, but particularly colostrum, contained higher concentrations of components considered to be derived from the fat-globule membrane (cholesterol, tocopherols, percentage long-chain polyunsaturated fatty acids) compared with those reported for Western countries. Percentage medium-chain fatty acids in mature milk was two to three times higher than in developed countries. Differences from data from studies in Western countries are discussed in relation to analytical methods and possible consequences for lipid digestion, lipid absorption, growth, and brain development.

Fatty acid and sn-2 fatty acid composition in human milk from Granada (Spain) and in infant formulas

“…We observed a significant increase for C 8:0 -C 14:0 between the colostrum group and the transitional and mature milk groups, which is consistent with similar findings reported from Spain (Barbas & Herrera, 1998) and different geographic areas (Pago-Gunsam et al, 1999;Boersma et al, 1991). These changes in milk composition may indicate variations in mammary gland biosynthetic capacity.…”

“…As we saw above, oleic acid (C 18:1 n-9), the main fatty acid, decreased as lactation progressed, which was consistent with similar findings reported from different geographic areas (Pago-Gunsam et al, 1999;Boersma et al, 1991). Although oleic acid is not an essential fatty acid, it is very important because, in addition to the usual functions of fatty acids (source of energy and structural components), it reduces the melting point of triacylglycerides, thus providing the liquidity required for the formation, transport and metabolism of milk fat globules ( Jensen, 1999).…”

Fatty acid composition of human milk in Western Iran

“…It is known that a maternal diet low in protein and fat but rich in carbohydrate causes an enhanced synthesis of short-and medium-chain length fatty acids by the mammary gland. It would therefore be expected to find these fatty acids in a higher proportion in milk of mothers on low-fat, low-energy diets (Aitchison et al, 1977;Boersma et al, 1991). Higher levels of medium-chain fatty acids (24%) and lower amounts of palmitic (11.4%) and stearic acids (4.0%) were found in the milk samples from our subjects as compared to those values reported for the Americans, Egyptians (Broschel et al, 1986) and also for vegetarian mothers (Finley et al, 1985).…”

“…Dietary intake, mobilization of body fat stores and endogenous synthesis by mammary glands are the sources of fatty acids in human milk (Francois et al, 1998). The influence of diet on milk fatty acid composition has been established by several studies (Aitchison et al, 1977;Boersma et al, 1991;Lawrence, 1994;Francois et al, 1998).…”

“…It is known that mammary cells are capable of synthesizing predominantly short-and medium-chain length fatty acids. Therefore, these fatty acids would be expected to be found with higher proportions in milk of mothers on low-energy diets (Aitchison et al, 1977;Boersma et al, 1991).…”