CHOLINE AND CHOLINE ESTERS IN HUMAN AND RAT MILK AND IN INFANT FORMULAS

Large amounts of choline are required in neonates for rapid organ grow th and membrane biosynthesis. Human infants derive much of their choli ne from milk. In our study mature human milk contained more phosphocho line and glycerophosphocholine than choline, phosphatidylcholine, or s phingomyelin (P < 0.01). Previous studies have not recognized that pho sphocholine and glycerophosphocholine exist in human milk. Concentrati ons of choline compounds in mature milk of mothers giving birth to pre term or full-term infants were not significantly different. infant for mulas also contained choline and choline-containing compounds. In infa nt formulas derived from soy or bovine milk, unesterified choline, pho sphocholine, glycerophosphocholine, phosphatidylcholine, and sphingomy elin concentrations varied greatly. All infant formulas contained sign ificantly less phosphocholine than did human milk. Soy-derived formula s contained significantly less glycerophosphocholine (P < 0.01) and ph osphocholine (P < 0.01) and more phosphatidylcholine (P < 0.01) than d id human or bovine milk or bovine milk-derived infant formulas. Rat mi lk contained greater amounts of glycerophosphocholine (almost 75% of t he total choline moiety in milk) and phosphocholine than did human mil k. When dams were provided with either a control, choline-deficient, o r choline-supplemented diet, milk composition reflected the choline ce ment of the diet. Because there are competing demands for choline in n eonates, it is important to ensure adequate availability through prope r infant nutrition. Although the free choline moiety is adequately pro vided by infant formulas and bovine milk, reevaluation of the concentr ations of other choline esters, in particular glycerophosphocholine an d phosphocholine may be warranted.