Franke Adrian A, Halm Brunhild M, Custer Laurie J, Tatsumura Yvonne, Hebshi Sandra
Cancer Research Center of Hawaii, Natural Products and Cancer Biology Program, Honolulu, HI, USA.
Am J Clin Nutr. 2006 Aug;84(2):406-13. doi: 10.1093/ajcn/84.1.406.
The bioavailability of isoflavones in children after soy exposure is uncertain.
We aimed to compare isoflavone patterns in infants exposed to isoflavone-containing breast milk (BF), in tofu-fed (TF) infants, and in mothers consuming a soy beverage.
Eighteen nursing mothers who were not feeding soy foods to their infants consumed one daily serving of a soy protein beverage for 2-4 d and collected their own milk and urine and infant urine. Plasma was collected from infants if venous blood draws were ordered by pediatricians. Blood and urine were collected from additional children after they consumed tofu. Isoflavones were measured by liquid chromatography-mass spectrometry.
In 7 subjects, isoflavone values increased significantly from baseline after mothers ate soy: in maternal urine (x +/- SEM) from 18.4 +/- 13.0 to 135.1 +/- 26.0 nmol/mg creatinine, in breast milk from 5.1 +/- 2.2 to 70.7 +/- 19.2 nmol/L, and in infant urine from 29.8 +/- 11.6 to 111.6 +/- 18.9 nmol/mg creatinine. The mean isoflavone concentration in plasma obtained from 11 BF infants was 19.7 +/- 13.2 nmol/L. TF infants had much higher mean isoflavone values (urine, 229 +/- 129 nmol/mg creatinine; plasma, 1049 +/- 403 nmol/L). Statistically significant correlations were observed between the types of fluids investigated within mothers, between mothers and infants, and within infants. Urinary isoflavone excretion per hour adjusted for dose per body weight was 81% lower for BF infants and 24% higher for TF infants than for their mothers after eating soy.
More isoflavones appear in children than in adults after adjustment for isoflavone intake. Systemic isoflavone exposure in infants can be determined by urinary analysis.
大豆摄入后儿童体内异黄酮的生物利用度尚不确定。
我们旨在比较食用含异黄酮母乳（BF）的婴儿、食用豆腐（TF）的婴儿以及饮用大豆饮料的母亲体内的异黄酮模式。
18名未给婴儿喂食大豆食品的哺乳期母亲连续2 - 4天每天饮用一份大豆蛋白饮料，并收集自己的乳汁、尿液以及婴儿尿液。若儿科医生要求采集静脉血，则从婴儿身上采集血浆。另外一些儿童食用豆腐后采集其血液和尿液。采用液相色谱 - 质谱法测定异黄酮。
7名受试者中，母亲食用大豆后异黄酮值较基线显著升高：母亲尿液中（x ± SEM）从18.4 ± 13.0增至135.1 ± 26.0 nmol/mg肌酐，母乳中从5.1 ± 2.2增至70.7 ± 19.2 nmol/L，婴儿尿液中从29.8 ± 11.6增至111.6 ± 18.9 nmol/mg肌酐。从11名食用母乳婴儿采集的血浆中异黄酮平均浓度为19.7 ± 13.2 nmol/L。食用豆腐的婴儿异黄酮平均含量更高（尿液中为229 ± 129 nmol/mg肌酐；血浆中为1049 ± 403 nmol/L）。在母亲体内不同类型体液之间、母亲与婴儿之间以及婴儿体内，所研究的体液类型之间存在统计学显著相关性。食用大豆后，按每体重剂量调整后的每小时尿异黄酮排泄量，食用母乳的婴儿比母亲低81%，食用豆腐的婴儿比母亲高24%。
经异黄酮摄入量调整后，儿童体内出现的异黄酮比成人更多。婴儿体内异黄酮的全身暴露情况可通过尿液分析来确定。
