Human requirement
The recommended dietary allowances of vitamin E for adults are based on the vitamin E content of the average American diet, assumed to be adequate as no biochemical or clinical evidence exists to indicate inadequate vitamin E intakes by healthy people ingesting balanced diets. Even though the daily intakes may vary considerably, the average over several days should fall between 7 mg and 13 mg d-a-tocopherol equivalents (10-20 IV) from diets supplying 1800 kcal to 3000 kcal. The recommended allowance for boys and men is 10 mg a-TE (15 IV), beginning at 15 years and 8 mg a-TE (12 IV) for girls and women, beginning at 11 years. Because requiremen ts for vi tamin E in the body tissues are reI a ted to their PUFA content, the Food and Nutrition Board has stressed that these recommendations should be considered as average adequate intakes in balanced diets in the United States, but the adequacy ofthese intakes will vary if the PUFA content of the diet deviates significantly from that which is customary.For this reason, these allowances are not expected to meet the needs of practically everyone as are the allowances for other vitamins. People with a high degree of polyunsaturation in their tissue lipids are also likely to have high vitamin E intakes, comparable to their requirements, because diets high in PUF A that result in high tissue polyunsaturation are also high in vitamin E. The allowance for infants (3-4 mg a:TE) is based on the vitamin E content of human milk, 1.3 to 3.3 mg a-TE per liter. Vitamin E allowances for children increase with increasing body weight. The adult female allowance for vitamin E is increased to 10 mg a-TE (15 IU) during pregnancy and to 11 mg a- TE during lacta tion.
The Food and Nutrition Committee of the American Academy of Pediatrics recommends that the formulas for LBW infants provide 0.5 mg (0.7 IU) of vitamin E per 100 kcal and at least 0.7 mg (1.0 IU) per gram oflinoleic acid because of the impaired utilization of vitamin E, related to the reduced fat absorption, in these infants. They also recommend a daily oral supplement of 3.3 mg (5 IU) of water-soluble a-tocophero
