Irvine C H, Fitzpatrick M G, Alexander S L
Animal and Veterinary Sciences Group, Lincoln University, Canterbury, New Zealand.
Proc Soc Exp Biol Med. 1998 Mar;217(3):247-53. doi: 10.3181/00379727-217-44229.
Exposure to estrogenic compounds may pose a developmental hazard to infants. Soy products, which contain the phytoestrogens, genistein and daidzein, are becoming increasingly popular as infant foods. To begin to evaluate the potential of the phytoestrogens in these products to affect infants, we measured total genistein and daidzein contents of commercially available soy-based infant formulas, infant cereals, dinners, and rusks. We also assayed phytoestrogens in dairy-based formulas and in breast milk from omnivorous or vegetarian mothers. In most cases, the glucoside forms of the phytoestrogens were hydrolyzed before separation by HPLC. Mean (+/-SEM) total genistein and daidzein contents in four soy infant formulas were 87+/-3 and 49+/-2 microg/g, respectively. The phytoestrogen content of cereals varied with brand, with genistein ranging from 3-287 microg/g and daidzein from 2-276 microg/g. By contrast, no phytoestrogens were detected in dairy-based infant formulas or in human breast milk, irrespective of the mother's diet (detection limit = 0.05 microg/ml). When fed according to the manufacturer's instruction, soy formulas provide the infant with a daily dose rate of total isoflavones (i.e., genistein + daidzein) of approximately 3 mg/kg body weight, which is maintained at a fairly constant level between 0-4 months of age. Supplementing the diet of 4-month-old infants with a single daily serving of cereal can increase their isoflavone intake by over 25%, depending on the brand chosen. This rate of isoflavone intake is much greater than that shown in adult humans to alter reproductive hormones. Since the available evidence suggests that infants can digest and absorb dietary phytoestrogens in active forms and since neonates are generally more susceptible than adults to perturbations of the sex steroid milieu, we suggest that it would be highly desirable to study the effects of soy isoflavones on steroid-dependent developmental processes in human babies.
接触雌激素化合物可能会对婴儿的发育构成危害。含有植物雌激素染料木黄酮和大豆苷元的豆制品，作为婴儿食品越来越受欢迎。为了开始评估这些产品中的植物雌激素对婴儿的潜在影响，我们测量了市售大豆基婴儿配方奶粉、婴儿谷物食品、晚餐食品和面包干中染料木黄酮和大豆苷元的总含量。我们还检测了以乳制品为基础的配方奶粉以及杂食或素食母亲的母乳中的植物雌激素。在大多数情况下，植物雌激素的糖苷形式在通过高效液相色谱法分离之前被水解。四种大豆婴儿配方奶粉中染料木黄酮和大豆苷元的平均（±标准误）总含量分别为87±3和49±2微克/克。谷物食品中的植物雌激素含量因品牌而异，染料木黄酮含量在3 - 287微克/克之间，大豆苷元含量在2 - 276微克/克之间。相比之下，在以乳制品为基础的婴儿配方奶粉或人母乳中未检测到植物雌激素，无论母亲的饮食如何（检测限 = 0.05微克/毫升）。按照制造商的说明喂养时，大豆配方奶粉为婴儿提供的总异黄酮（即染料木黄酮 + 大豆苷元）日剂量率约为3毫克/千克体重，在0至4个月龄之间保持在相当恒定的水平。根据所选品牌的不同，给4个月大的婴儿每天补充一份谷物食品可以使其异黄酮摄入量增加超过25%。这种异黄酮摄入量远远高于在成年人中显示会改变生殖激素的摄入量。由于现有证据表明婴儿能够消化和吸收活性形式的膳食植物雌激素，并且由于新生儿通常比成年人更容易受到性类固醇环境干扰的影响，我们建议非常有必要研究大豆异黄酮对人类婴儿类固醇依赖性发育过程的影响。
