UBC Theses and Dissertations
Vitamin E status of infant formulas. O'Leary, Lillian Patricia
In early Infancy, limited ingestion of vitamin E, especially the α-tocopherol form, and/or a high, intake of polyunsaturated fatty acids are reflected as a low serum tocopherol level. This vitamin E deficiency state is probably responsible for the development of an anemia characterized by abnormal erythrocyte hemolysis. Edema and skin changes may also be present. In order to ascertain the tocopherol status of infant formulas available in Canada, thirty-six representative formulas were chemically analyzed for vitamin E and polyunsaturated fatty acid contents. For the tocopherol analysis, a combination of the Emmerie-Engel procedure and two-dimensional thin-layer chromatography was used. An alkaline isomerization technique was chosen for the polyunsaturated fatty acid analysis. The vitamin E status of the various formulas was assessed in relation to three criteria of tocopherol adequacy - the α-tocopherol-to-PUFA ratio, the α-tocopherol content, and the level of International Units of vitamin E. With the exception of one formula which was supplemented with vitamin E, the twenty-one formulas based on fresh or modified cow's milk often contained insufficient tocopherol to meet the various criteria of adequacy. A large per cent of the vitamin E content in these formulas was present as α-tocopherol. The polyunsaturated fatty acid content was relatively low. In general, the fifteen proprietary formulas had much higher levels of vitamin E and polyunsaturated fatty acids than the formulas based on fresh or modified cow's milk. For many of the proprietary products, α-tocopherol constituted only a small part of the vitamin E content. Four of the proprietary formulas (including three which had been fortified with vitamin E) contained sufficient amounts of vitamin E to satisfy the three standards of adequacy. On the basis of the chemical analysis results, it is recommended that all infant formulas be supplemented with sufficient amounts of vitamin E. to meet the various criteria of adequacy. In this way, the risk of vitamin E deficiency in early childhood should be minimal. The present study is also concerned with past, present, and future trends in infant feeding practices. In the 1960's, the ready-to-feed hospital feeding systems, which are usually based on a proprietary preparation,were introduced in Canada. A survey conducted among Canadian hospitals indicated that the use of such systems has become widespread. At the same time, the popularity of the hospital-prepared formula system has declined. Consequently, the use of modified cow's milk formulas has declined in Canadian hospitals. However, such formulas are frequently used for home-feeding of infants. No definite trends were noted in the frequency of breast-feeding.
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