本研究分析台北及台中夜市臭豆腐各種大豆異黃酮含量，及嗜好者一般攝取頻率與量，並分析可產生與不可產生equol者攝取市售一份臭豆腐後之尿液異黃酮動力學。

由122 家臭豆腐店面及攤販，收集143 種臭豆腐樣品，以HPLC分析異黃酮的含量，結果發現每100 g臭豆腐平均含 daidzein 9.32 mg (glycosides 3.81 mg & aglycon 5.51 mg)、genistein 12.81 mg (glycosides 6.31 mg & aglycon 6.50 mg)、glycitein 1.27 mg (glycosides 0.39 mg, aglycon 0.88 mg)，及daidzein之代謝物dihydrodaidzein 0.36 mg、equol 1.16 mg、desmethylangolesin 0.01 mg、dihydrogenistein 0.55 mg。去醣基之異黃酮約佔總異黃酮量 49.7±27.2 %。

對 274位有攝取臭豆腐習慣者進行臭豆腐攝取頻率調查，發現18.3%的受訪者每週攝取1-2次以上，46.4 %每月攝取1-3次，24.8 %每3個月攝取1-2次，每人每次攝食量平均為195.0 ± 79.6 g。

另於校園招募74 位20-30 歲臭豆腐嗜好者，服用異黃酮三天後，分析尿液equol，分辨出52人 (70.3 %) 為equol producer，22人 ( 29.7 %) 為 equol non-producer，由其中挑選20位equol producer，18位 equol non-producer，給予一份臭豆腐後，收集48小時尿液 (4 個1小時尿液，4 個2小時尿液與 3 個 12 小時尿液) 分析異黃酮排出量。結果發現 0-1 小時即有 daidzein、equol、genistein、glycitein 排出，並於 3-4 小時內達最大排出速率，36-48 小時內排出趨近為 0。dihydrodaidzein、desmethylangolesin，則於吃後 1-4 小時出現，10-12 小時內達最大排出速率。equol producer 和 non-producer兩組的daidzein、equol、genistein 排出量與速率在 10-12 小時內，開始出現差異；兩組的dihydrodaidzein、desmethylangolesin 排出量與速率在12-24 內開始出現差異，表示臭豆腐中 daidzein 和 genistein 代謝產物於攝取後 10 小時出現，兩組glycitein 0-48 小時內排出量與速率皆無差異。總 daidzein 類攝取在尿液回收 75.9 %、equol 回收 67.4 %、總 genistein 類回收 41.8 %、總 glycitein 類回收 65.3 %。另比較 equol producer 和 equol non-producer 黃豆製品攝取量、臭豆腐攝取量、排便頻率皆無顯著差異。

結論，臭豆腐中去醣基異黃酮含量高，並富含 equol，可為提供 equol 來源食物。無論 equol producer 或 equol non-producer 攝取臭豆腐後皆對其異黃酮吸收快、吸收率高。另外發現嗜好臭豆腐之台灣年輕人具良好 equol 產生能力，有待進一步研究確認原因。

This research analyzed isoflavones content in stinky tofu from night markets in Taipei and Taichung, consumption frequency of stinky tofu by hobbyists, and urinary pharmacokinetics of isoflavones following a single ingestion of stinky tofu by equol producers and non-producers.

We collected 143 stinky tofu samples from 122 vendors and analyzed the isoflavones content by HPLC (high-performance liquid chromatography). The results showed that the average contents in every 100 g of stinky tofu were 9.32 mg of daidzein (including glycosides 3.81 mg and aglycon 5.51 mg), 12.81 mg of genistein (including glycosides 6.31 mg and aglycon 6.50 mg), 1.27 mg of glycitein (including glycosides 0.39 mg and aglycon 0.88 mg), 0.36 mg of dihydrodaidzein, 1.16 mg of equol, 0.01 mg of desmethylangolesin, and 0.55 mg of dihydrogenistein. The percentage of aglycone isoflavone is 49.7±27.2.

We also surveyed 274 respondents with habit of eating stinky tofu for their stinky tofu intake frequency. We found that 18.3% of the respondents take more than 1–2 times per week, 46.4% of them take 1–3 times per month, and 24.8% of them take 1–2 times per quarter. The average amount of each intake is 195.0± 79.6 g.

We recruited 74 stinky tofu hobbyists within 20–30 years old and analyzed their equol content in urine after challenging soy isoflavone for 3 days, that were identified 52 of them (70.3%) are equol producers and 22 of them (29.7%) are equol non-producers. We selected 20 equol producers and 18 equol non-producers, collect their urine in the 48 hours after one serving of stinky tofu (four 1-hour urine samples, four 2-hour urine samples and three 12-hour urine samples), and analyzed urinary isoflavone content. We found that daidzein, equol, genistein and glycitein were excreted within 0–1 hour, and it reached peak excretion rate after 3–4 hours. The excretion amount approached 0 after 36–48 hours. Dihydrodaidzein and desmethylangolesin started to be excreted 1–4 after serving stinky tofu, and it reached peak excresion rate in 10–12 hours. The difference of daidzein, equol and genistein excretion amount and rate between equol producers and non-producers appeared to be significant in 10–12 hours; the difference of dihydrodaidzein and desmethylangolesin appeared to be significant in 12–24 hours. That means, the metabolites of daidzein and genistein in stinky tofu appeared 10 hours after intaking. The excretion amount and rate difference of glycitein between equol producers and non-producers was insignificant within 0–48 hours. Recovery of urine isoflavones is 75.9 % of total daidzein, 67.4 % of equol, 41.8 % of total genistein and 65.3 % of total glycitein. The equol producers had similar amount of soy food intake, stinky tofu intake and defecation frequency as compared with the equol non-producers.

Our results show that the aglycone isoflavones content in stinky tofu are rich, especially containing equol. And the absorption rates are high for both equol producers and non-producers. Stinky tofu could serve as an equol source. It requires further research to justify if the proportion of equol producers is higher among young stinky tofu hobbyists.

中文部分:
朱苑蓉.(2007). 豆製加工品中異黃酮含量之變化. 私立輔仁大學, 碩士論文
黃日青.(2008). 添加物和儲存對豆腐和豆腐乳中異黃酮安定性的影響. 私立輔 仁大學, 碩士論文
常致綱.(2006). 大豆異黃酮定量方法之改良及加工方式對大豆異黃酮種類轉換 之研究. 國立台灣大學, 碩士論文
辜克筠.(2005). 幼兒飲食頻率問卷之信度及效度之評估. 私立輔仁大學, 碩士 論文
黃秋薇.(2000). Isoflavones 對賀爾蒙補充治療之停經婦女血脂與脂蛋白及尿 液雌激素代謝物的影響. 國立台灣師範大學, 碩士論文
李淑芬, 王吉彬, 張平平.(1996). 臭豆腐中蛋白質分解細菌之分離與鑑定。 食品科學23: 1-9。

英文部分:
Andres, S., Abraham, K., Appel, K. E., & Lampen, A. (2011). Risks and benefits of dietary isoflavones for cancer. Crit Rev Toxicol, 41(6), 463-506. Arora, A., Nair, M. G., & Strasburg, G. M. (1998). Antioxidant activities of isoflavones and their biological metabolites in a liposomal system. Arch Biochem Biophys, 356(2), 133-141.
Atkinson, C., Newton, K. M., Bowles, E. J., Yong, M., & Lampe, J. W. (2008). Demographic, anthropometric, and lifestyle factors and dietary intakes in relation to daidzein-metabolizing phenotypes among premenopausal women in the United States. American Journal of Clinical Nutrition, 87(3), 679-687. Back, H. I., Kim, S. R., Yang, J. A., Kim, M. G., Chae, S. W., & Cha, Y. S. (2011). Effects of Chungkookjang supplementation on obesity and atherosclerotic indices in overweight/obese subjects: a 12-week, randomized, double-blind, placebo-controlled clinical trial. Journal of Medicinal Food, 14(5), 532-537. Barnes, S. (2010). The biochemistry, chemistry and physiology of the isoflavones in soybeans and their food products. Lymphat Res Biol, 8(1), 89-98. Blake, C., Fabick, K. M., Setchell, K. D., Lund, T. D., & Lephart, E. D. (2011). Neuromodulation by soy diets or equol: anti-depressive & anti-obesity-like influences, age- & hormone-dependent effects. BMC Neurosci, 12, 28. Bosviel, R., Durif, J., Dechelotte, P., Bignon, Y. J., & Bernard-Gallon, D. (2012). Epigenetic modulation of BRCA1 and BRCA2 gene expression by equol in breast cancer cell lines. Br J Nutr, 1-7. Chan, S. G., Ho, S. C., Kreiger, N., Darlington, G., Adlaf, E. M., So, K. F., et al. (2008). Validation of a food frequency questionnaire for assessing dietary soy isoflavone intake among midlife Chinese women in Hong Kong. J Nutr, 138(3), 567-573. Chang, C. H., Chen, K. T., Lee, T. H., Wang, C. H., Kuo, Y. W., Chiu, Y. H., et al. (2010). Effects of natto extract on endothelial injury in a rat model. Acta Med Okayama, 64(6), 399-406. Chao, S. H., Tomii, Y., Sasamoto, M., Fujimoto, J., Tsai, Y. C., & Watanabe, K. (2008). Lactobacillus capillatus sp. nov., a motile bacterium isolated from stinky tofu brine. Int J Syst Evol Microbiol, 58(Pt 11), 2555-2559. Chiang, S. S., & Pan, T. M. (2011). Antiosteoporotic effects of lactobacillus -fermented soy skim milk on bone mineral density and the microstructure of femoral bone in ovariectomized mice. J Agric Food Chem, 59(14), 7734-7742.
Chien, H. L., Huang, H. Y., & Chou, C. C. (2006). Transformation of isoflavone phytoestrogens during the fermentation of soymilk with lactic acid bacteria and bifidobacteria. Food Microbiol, 23(8), 772-778. Day, A. J., Canada, F. J., Diaz, J. C., Kroon, P. A., McLauchlan, R., Faulds, C. B., et al. (2000). Dietary flavonoid and isoflavone glycosides are hydrolysed by the lactase site of lactase phlorizin hydrolase. FEBS Lett, 468(2-3), 166-170. Decroos, K., Eeckhaut, E., Possemiers, S., & Verstraete, W. (2006). Administration of equol-producing bacteria alters the equol production status in the Simulator of the Gastrointestinal Microbial Ecosystem (SHIME). J Nutr, 136(4), 946-952. Di Cagno, R., Mazzacane, F., Rizzello, C. G., Vincentini, O., Silano, M., Giuliani, G., et al. (2010). Synthesis of isoflavone aglycones and equol in soy milks fermented by food-related lactic acid bacteria and their effect on human intestinal Caco-2 cells. J Agric Food Chem, 58(19), 10338-10346. Ding, W. K., & Shah, N. P. (2010). Enhancing the biotransformation of isoflavones in soymilk supplemented with lactose using probiotic bacteria during extended fermentation. J Food Sci, 75(3), M140-149. Faughnan, M. S., Hawdon, A., Ah-Singh, E., Brown, J., Millward, D. J., & Cassidy, A. (2004). Urinary isoflavone kinetics: the effect of age, gender, food matrix and chemical composition. Br J Nutr, 91(4), 567-574. Fujimoto, K., Tanaka, M., Hirao, Y., Nagata, Y., Mori, M., Miyanaga, N., et al. (2008). Age-stratified serum levels of isoflavones and proportion of equol producers in Japanese and Korean healthy men. Prostate Cancer Prostatic Dis, 11(3), 252-257. Gardana, C., Canzi, E., & Simonetti, P. (2009). The role of diet in the metabolism of daidzein by human faecal microbiota sampled from Italian volunteers. J Nutr Biochem, 20(12), 940-947. Haron, H., Ismail, A., Shahar, S., Azlan, A., & Peng, L. S. (2011a). Apparent bioavailability of isoflavones in urinary excretions of postmenopausal Malay women consuming tempeh compared with milk. Int J Food Sci Nutr, 62(6), 642-650. Haron, H., Ismail, A., Shahar, S., Azlan, A., & Peng, L. S. (2011b). Apparent bioavailability of isoflavones in urinary excretions of postmenopausal Malay women consuming tempeh compared with milk. Int J Food Sci Nutr. Heinonen, S. M., Hoikkala, A., Wahala, K., & Adlercreutz, H. (2003). Metabolism of the soy isoflavones daidzein, genistein and glycitein in human subjects. Identification of new metabolites having an intact isoflavonoid skeleton. J Steroid Biochem Mol Biol, 87(4-5), 285-299.
Hoey, L., Rowland, I. R., Lloyd, A. S., Clarke, D. B., & Wiseman, H. (2004).
Influence of soya-based infant formula consumption on isoflavone and gut microflora metabolite concentrations in urine and on faecal microflora composition and metabolic activity in infants and children. Br J Nutr, 91(4), 607-616. Hong, Y. H., Huang, C. J., Wang, S. C., & Lin, B. F. (2009). The ethyl acetate extract of alfalfa sprout ameliorates disease severity of autoimmune-prone MRL-lpr/lpr mice. Lupus, 18(3), 206-215. Hu, Y., Ge, C., Yuan, W., Zhu, R., Zhang, W., Du, L., et al. (2010). Characterization of fermented black soybean natto inoculated with Bacillus natto during fermentation. J Sci Food Agric, 90(7), 1194-1202. Ishiwata, N., Melby, M. K., Mizuno, S., & Watanabe, S. (2009). New equol supplement for relieving menopausal symptoms: randomized, placebo-controlled trial of Japanese women. Menopause, 16(1), 141-148. Kang, J. S., Yoon, Y. D., Han, M. H., Han, S. B., Lee, K., Park, S. K., et al. (2007). Equol inhibits nitric oxide production and inducible nitric oxide synthase gene expression through down-regulating the activation of Akt. Int Immunopharmacol, 7(4), 491-499. Kelly, G. E., Joannou, G. E., Reeder, A. Y., Nelson, C., & Waring, M. A. (1995). The variable metabolic response to dietary isoflavones in humans. Proc Soc Exp Biol Med, 208(1), 40-43. Kim, J., Kang, M., Lee, J. S., Inoue, M., Sasazuki, S., & Tsugane, S. (2011). Fermented and non-fermented soy food consumption and gastric cancer in Japanese and Korean populations: a meta-analysis of observational studies. Cancer Sci, 102(1), 231-244. King, R. A., & Bursill, D. B. (1998). Plasma and urinary kinetics of the isoflavones daidzein and genistein after a single soy meal in humans. American Journal of Clinical Nutrition, 67(5), 867-872. Kirk, P., Patterson, R. E., & Lampe, J. (1999). Development of a soy food frequency questionnaire to estimate isoflavone consumption in US adults. J Am Diet Assoc, 99(5), 558-563. Knight, D. C., & Eden, J. A. (1996). A review of the clinical effects of phytoestrogens. Obstet Gynecol, 87(5 Pt 2), 897-904. Ko, T. F., Tsai, H. S., Lin, S. M., Liu, C. D., Learn, S. P., & Chiou, R. Y. (2010). GC-MS determined distribution of urinary equol producers as affected by age, gender, and repeated ingestions of soymilk. J Food Sci, 75(9), H306-310. Kudou, S., Fleury, Y., Welti, D., Magnolato, D., Uchida, T., Kitamura, K., et al. (1991). Malonyl Isoflavone Glycosides in Soybean Seeds (Glycine-Max Merrill). Agricultural and Biological Chemistry, 55(9), 2227-2233.
Kuhnle, G. G., Dell'Aquila, C., Aspinall, S. M., Runswick, S. A., Mulligan, A. A., & Bingham, S. A. (2008a). Phytoestrogen content of beverages, nuts, seeds, and oils. J Agric Food Chem, 56(16), 7311-7315. Kuhnle, G. G., Dell'Aquila, C., Aspinall, S. M., Runswick, S. A., Mulligan, A. A., & Bingham, S. A. (2008b). Phytoestrogen content of foods of animal origin: dairy products, eggs, meat, fish, and seafood. J Agric Food Chem, 56(21), 10099-10104. Kuiper, G. G., Lemmen, J. G., Carlsson, B., Corton, J. C., Safe, S. H., van der Saag, P. T., et al. (1998). Interaction of estrogenic chemicals and phytoestrogens with estrogen receptor beta. Endocrinology, 139(10), 4252-4263. Kwon, D. Y., Daily, J. W., 3rd, Kim, H. J., & Park, S. (2010). Antidiabetic effects of fermented soybean products on type 2 diabetes. Nutr Res, 30(1), 1-13. Lampe, J. W., Skor, H. E., Li, S., Wahala, K., Howald, W. N., & Chen, C. (2001). Wheat bran and soy protein feeding do not alter urinary excretion of the isoflavan equol in premenopausal women. J Nutr, 131(3), 740-744. Larkin, T., Price, W. E., & Astheimer, L. (2008). The key importance of soy isoflavone bioavailability to understanding health benefits. Crit Rev Food Sci Nutr, 48(6), 538-552. Lund, T. D., Blake, C., Bu, L., Hamaker, A. N., & Lephart, E. D. (2011). Equol an isoflavonoid: potential for improved prostate health, in vitro and in vivo evidence. Reprod Biol Endocrinol, 9, 4. Lundh, T. J., Pettersson, H., & Kiessling, K. H. (1988). Liquid chromatographic determination of the estrogens daidzein, formononetin, coumestrol, and equol in bovine blood plasma and urine. J Assoc Off Anal Chem, 71(5), 938-941. Messina, M. (2010). A brief historical overview of the past two decades of soy and isoflavone research. J Nutr, 140(7), 1350S-1354S. Mortensen, A., Kulling, S. E., Schwartz, H., Rowland, I., Ruefer, C. E., Rimbach, G., et al. (2009). Analytical and compositional aspects of isoflavones in food and their biological effects. Mol Nutr Food Res, 53 Suppl 2, S266-309. Murooka, Y., & Yamshita, M. (2008). Traditional healthful fermented products of Japan. J Ind Microbiol Biotechnol, 35(8), 791-798. Nishikawa, Y., Takata, Y., Nagai, Y., Mori, T., Kawada, T., & Ishihara, N. (2001). Antihypertensive effect of Kurosu extract, a traditional vinegar produced from unpolished rice, in the SHR rats. Journal of the Japanese Society for Food Science and Technology-Nippon Shokuhin Kagaku Kogaku Kaishi, 48(1), 73-75.
Oyama, A., Ueno, T., Uchiyama, S., Aihara, T., Miyake, A., Kondo, S., et al. (2011). The effects of natural S-equol supplementation on skin aging in postmenopausal women: a pilot randomized placebo-controlled trial. Menopause. Park, C. U., Jeong, M. K., Park, M. H., Yeu, J., Park, M. S., Kim, M. J., et al. (2010). Formation of succinyl genistin and succinyl daidzin by Bacillus species. J Food Sci, 75(1), C128-133. Rufer, C. E., Glatt, H., & Kulling, S. E. (2006). Structural elucidation of hydroxylated metabolites of the isoflavan equol by gas chromatography-mass spectrometry and high-performance liquid chromatography-mass spectrometry. Drug Metab Dispos, 34(1), 51-60. Saitoh, S., Sato, T., Harada, H., & Matsuda, T. (2004). Biotransformation of soy isoflavone-glycosides in laying hens: intestinal absorption and preferential accumulation into egg yolk of equol, a more estrogenic metabolite of daidzein. Biochim Biophys Acta, 1674(2), 122-130. Setchell, K. D., Brown, N. M., Desai, P., Zimmer-Nechemias, L., Wolfe, B. E., Brashear, W. T., et al. (2001). Bioavailability of pure isoflavones in healthy humans and analysis of commercial soy isoflavone supplements. J Nutr, 131(4 Suppl), 1362S-1375S. Setchell, K. D., Brown, N. M., Desai, P. B., Zimmer-Nechimias, L., Wolfe, B., Jakate, A. S., et al. (2003). Bioavailability, disposition, and dose-response effects of soy isoflavones when consumed by healthy women at physiologically typical dietary intakes. Journal of Nutrition, 133(4), 1027-1035. Setchell, K. D., Brown, N. M., & Lydeking-Olsen, E. (2002). The clinical importance of the metabolite equol-a clue to the effectiveness of soy and its isoflavones. Journal of Nutrition, 132(12), 3577-3584. Setchell, K. D., & Clerici, C. (2010a). Equol: history, chemistry, and formation. Journal of Nutrition, 140(7), 1355S-1362S. Setchell, K. D., & Clerici, C. (2010b). Equol: pharmacokinetics and biological actions. J Nutr, 140(7), 1363S-1368S. Setchell, K. D., & Cole, S. J. (2006a). Method of defining equol-producer status and its frequency among vegetarians. Journal of Nutrition, 136(8), 2188-2193. Setchell, K. D., & Cole, S. J. (2006b). Method of defining equol-producer status and its frequency among vegetarians. J Nutr, 136(8), 2188-2193. Setchell, K. D., Zhao, X., Jha, P., Heubi, J. E., & Brown, N. M. (2009). The pharmacokinetic behavior of the soy isoflavone metabolite S-(-)equol and its diastereoisomer R-(+)equol in healthy adults determined by using stable-isotope-labeled tracers. American Journal of Clinical Nutrition, 90(4), 1029-1037.
Setchell, K. D., Zhao, X., Shoaf, S. E., & Ragland, K. (2009a). The pharmacokinetics of S-(-)equol administered as SE5-OH tablets to healthy postmenopausal women. Journal of Nutrition, 139(11), 2037-2043. Setchell, K. D., Zhao, X., Shoaf, S. E., & Ragland, K. (2009b). The pharmacokinetics of S-(-)equol administered as SE5-OH tablets to healthy postmenopausal women. J Nutr, 139(11), 2037-2043. Shelnutt, S. R., Cimino, C. O., Wiggins, P. A., & Badger, T. M. (2000). Urinary pharmacokinetics of the glucuronide and sulfate conjugates of genistein and daidzein. Cancer Epidemiol Biomarkers Prev, 9(4), 413-419. Shoff, S. M., Newcomb, P. A., Mares-Perlman, J. A., Klein, B. E., Haffner, S. M., Storer, B. E., et al. (1998). Usual consumption of plant foods containing phytoestrogens and sex hormone levels in postmenopausal women in Wisconsin. Nutrition and Cancer-an International Journal, 30(3), 207-212. Simons, A. L., Renouf, M., Hendrich, S., & Murphy, P. A. (2005). Metabolism of glycitein (7,4'-dihydroxy-6-methoxy-isoflavone) by human gut microflora. J Agric Food Chem, 53(22), 8519-8525. Taniguchi, A., Yamanaka-Okumura, H., Nishida, Y., Yamamoto, H., Taketani, Y., & Takeda, E. (2008). Natto and viscous vegetables in a Japanese style meal suppress postprandial glucose and insulin responses. Asia Pac J Clin Nutr, 17(4), 663-668. Thompson, L. U., Boucher, B. A., Liu, Z., Cotterchio, M., & Kreiger, N. (2006). Phytoestrogen content of foods consumed in Canada, including isoflavones, lignans, and coumestan. Nutr Cancer, 54(2), 184-201. Thorp, A. A., Howe, P. R., Mori, T. A., Coates, A. M., Buckley, J. D., Hodgson, J., et al. (2008). Soy food consumption does not lower LDL cholesterol in either equol or nonequol producers. American Journal of Clinical Nutrition, 88(2), 298-304. Tousen, Y., Ezaki, J., Fujii, Y., Ueno, T., Nishimuta, M., & Ishimi, Y. (2011). Natural S-equol decreases bone resorption in postmenopausal, non-equol-producing Japanese women: a pilot randomized, placebo-controlled trial. Menopause, 18(5), 563-574. Turner, N. J., Thomson, B. M., & Shaw, I. C. (2003). Bioactive isoflavones in functional foods: the importance of gut microflora on bioavailability. Nutr Rev, 61(6 Pt 1), 204-213. Vedrine, N., Mathey, J., Morand, C., Brandolini, M., Davicco, M. J., Guy, L., et al. (2006). One-month exposure to soy isoflavones did not induce the ability to produce equol in postmenopausal women. Eur J Clin Nutr, 60(9), 1039-1045.
Vergne, S., Titier, K., Bernard, V., Asselineau, J., Durand, M., Lamothe, V., et al. (2007). Bioavailability and urinary excretion of isoflavones in humans: effects of soy-based supplements formulation and equol production. J Pharm Biomed Anal, 43(4), 1488-1494. Verheus, M., van Gils, C. H., Kreijkamp-Kaspers, S., Kok, L., Peeters, P. H., Grobbee, D. E., et al. (2008). Soy protein containing isoflavones and mammographic density in a randomized controlled trial in postmenopausal women. Cancer Epidemiol Biomarkers Prev, 17(10), 2632-2638. Vrieling, A., Rookus, M. A., Kampman, E., Bonfrer, J. M., Korse, C. M., van Doorn, J., et al. (2007). Isolated isoflavones do not affect the circulating insulin-like growth factor system in men at increased colorectal cancer risk. J Nutr, 137(2), 379-383. Wang, H. J., & Murphy, P. A. (1994). Isoflavone Content in Commercial Soybean Foods. Journal of Agricultural and Food Chemistry, 42(8), 1666-1673. Watanabe, S., Yamaguchi, M., Sobue, T., Takahashi, T., Miura, T., Arai, Y., et al. (1998a). Pharmacokinetics of soybean isoflavones in plasma, urine and feces of men after ingestion of 60 g baked soybean powder (kinako). Journal of Nutrition, 128(10), 1710-1715. Watanabe, S., Yamaguchi, M., Sobue, T., Takahashi, T., Miura, T., Arai, Y., et al. (1998b). Pharmacokinetics of soybean isoflavones in plasma, urine and feces of men after ingestion of 60 g baked soybean powder (kinako). J Nutr, 128(10), 1710-1715. Wu, J., Oka, J., Ezaki, J., Ohtomo, T., Ueno, T., Uchiyama, S., et al. (2007). Possible role of equol status in the effects of isoflavone on bone and fat mass in postmenopausal Japanese women: a double-blind, randomized, controlled trial. Menopause, 14(5), 866-874.