Stegink L D, Wolf-Novak L C, Filer L J, Bell E F, Ziegler E E, Krause W L, Brummel M C
Department of Pediatrics, University of Iowa College of Medicine, Iowa City 52242.
J Nutr. 1987 Nov;117(11):1989-95. doi: 10.1093/jn/117.11.1989.
Twelve normal subjects ingested either unsweetened beverage (n = 6) or beverage providing 4 mg/kg body weight as aspartame (APM) (n = 6). Neither beverage had any significant effect on plasma aspartate or phenylalanine concentrations. After this study, eight normal and six obligate phenylketonuric (PKU) heterozygous adults each ingested a 354-mL (12-oz) beverage serving on two occasions in a randomized cross-over design. On one occasion the beverage was not sweetened; on the other occasion, the beverage provided 10 mg APM/kg body weight. Plasma amino acid concentrations were measured throughout the 2-h study period. The addition of 10 mg APM/kg body weight to the beverage had no significant effect on plasma aspartate concentration. APM ingestion increased plasma phenylalanine levels of normal subjects from a mean +/- SD baseline value of 5.09 +/- 0.82 mumol/dL to a high mean value of 6.73 +/- 0.75 mumol/dL. In PKU heterozygous subjects the plasma phenylalanine level increased from a mean +/- SD of 9.04 +/- 1.71 to a high mean value of 12.1 +/- 2.08 mumol/dL. The data indicate ready metabolism of the aspartate and phenylalanine portion of APM when administered at levels likely to be ingested by individuals who drink diet beverages.
12名正常受试者分别饮用无糖饮料（n = 6）或每千克体重摄入4毫克阿斯巴甜（APM）的饮料（n = 6）。两种饮料对血浆天冬氨酸或苯丙氨酸浓度均无显著影响。本研究之后，8名正常成年人及6名苯丙酮尿症（PKU）杂合子成年人采用随机交叉设计，每人分两次饮用一份354毫升（12盎司）的饮料。一次饮用无糖饮料，另一次饮用的饮料每千克体重含10毫克APM。在整个2小时的研究期间测量血浆氨基酸浓度。饮料中添加每千克体重10毫克APM对血浆天冬氨酸浓度无显著影响。正常受试者摄入APM后，血浆苯丙氨酸水平从平均±标准差基线值5.09±0.82微摩尔/分升升高至较高的平均值6.73±0.75微摩尔/分升。在PKU杂合子受试者中，血浆苯丙氨酸水平从平均±标准差的9.04±1.71升高至较高的平均值12.1±2.08微摩尔/分升。数据表明，当以饮用低热量饮料的个体可能摄入的水平给予APM时，其天冬氨酸和苯丙氨酸部分易于代谢。
