Effect of the cholesterol content of a formula on the lipid compositions of plasma lipoproteins and red blood cell membranes in early infancy.

We investigated whether or not a regular formula for full-term infants supplemented with cholesterol (cholesterol-fortified) would increase the plasma cholesterol concentration and alter the red blood cell (RBC) membrane lipid composition in healthy full-term infants compared with their breast-fed counterparts. At 1 mo of age, total plasma cholesterol and low-density-lipoprotein (LDL) cholesterol were significantly higher in the breast-fed infants than in the cholesterol-unfortified, formula-fed infants. At 3 mo of age, total cholesterol and LDL cholesterol were significantly higher in the breast-fed infants than in the two formula-fed infant groups. These significant differences had disappeared by 6 mo of age. Although the cholesterol-unfortified, formula-fed infants had lower proportions of docosahexaenoic acid (DHA, 22:6n-3) and eicosapentaenoic acid (EPA, 20:5n-3) in the RBC membranes compared with the breast-fed group at 6 mo, DHA and EPA concentrations in the cholesterol-fortified, formula-fed infants were not significantly different. The results of the present study suggest that the plasma cholesterol concentration and fatty acid pattern of the RBC membranes in infants fed a cholesterol-fortified formula may be much closer to those in breast-fed infants than in infants fed a cholesterol-unfortified formula.