Bell E F
Department of Pediatrics, University of Iowa, Iowa City 52242.
J Nutr. 1989 Dec;119(12 Suppl):1829-31. doi: 10.1093/jn/119.12_Suppl.1829.
Reports of toxicity to enterally administered vitamin E are rare in infants. However, increased risks of sepsis and necrotizing enterocolitis have been reported after both enteral and parenteral vitamin E, primarily when plasma (or serum) vitamin E levels exceed 3.5 mg/dl. Levels this high are seldom seen with enteral vitamin E when intake is 25 mg d-alpha-tocopherol equivalent/(kg.d) or less. Intakes below this threshold will be provided by infant formulas with vitamin E to energy ratios of up to 20 mg/100 kcal (30 IU/100 kcal) so long as energy intake does not exceed 125 kcal/(kg.d). To allow a margin of safety, it would be reasonable to limit the amount of vitamin E added to the formula during its manufacture to half this amount, or 10 mg/100 kcal (15 IU/100 kcal). This level coincides with the highest levels of vitamin E found in human colostrum and is 20 times the recommended lower limit for vitamin E in infant formula of 0.5 mg/100 kcal.
关于婴儿经肠道给予维生素E出现毒性反应的报道很少。然而，经肠道和肠道外给予维生素E后，均有败血症和坏死性小肠结肠炎风险增加的报道，主要是当血浆（或血清）维生素E水平超过3.5mg/dl时。当摄入量为25mg d-α-生育酚当量/（kg·d）或更低时，经肠道给予维生素E很少出现这么高的水平。只要能量摄入量不超过125kcal/（kg·d），维生素E与能量比高达20mg/100kcal（30IU/100kcal）的婴儿配方奶粉就能提供低于此阈值的摄入量。为了保证安全边际，在配方奶粉生产过程中将添加的维生素E量限制在这个量的一半，即10mg/100kcal（15IU/100kcal）是合理的。这个水平与人类初乳中发现的维生素E最高水平一致，是婴儿配方奶粉中维生素E推荐下限0.5mg/100kcal的20倍。
