There are numerous clinical studies showing increased risks of breast cancer, Alzheimer's and digestive tract problems with non-fermented soy. An infant drinking soy milk is consuming an amount of estrogen equivalent of 5 birth-control pills per day.
This is also a grossly misleading if not a completely false statement. At best, the scientific evidence is inconclusive. There are conflicting studies, however I don't know of any meta-analysis that have concluded anything remotely close to what you clam. Rather, they have as far as I know, concluded the opposite or that there is not enough information available.
1 Others have shown reduction in certain cancers such as prostrate in men and colorectal in women and a reduction in recurrence and lower morbidity in breast cancer.
2 Further, soy milk contains zero estrogen (5 birth-control pills per day? - If you read it on the internet, it has to be true, right?) It contains phytoestrogens which can mildly mimic estrogen. However, there is no conclusive scientific evidence of any ill effects on humans, and multiple studies have shown no adverse effects in humans as a result of consuming soy-based infant formula compared cow's milk based formula.
3References1 Messina, M.; McCaskill-Stevens, W.; Lampe, J. W. (September 2006). "Addressing the Soy and Breast Cancer Relationship: Review, Commentary, and Workshop Proceedings". JNCI Journal of the National Cancer Institute (National Cancer Institute) 98 (18): 1275–1284. doi:10.1093/jnci/djj356. PMID 16985246.
Hamilton-Reeves, Jill M.; Vazquez, Gabriela; Duval, Sue J.; Phipps, William R.; Kurzer, Mindy S.; Messina, Mark J. (2010). "Clinical studies show no effects of soy protein or isoflavones on reproductive hormones in men: Results of a meta-analysis". Fertility and Sterility 94 (3): 997–1007. doi:10.1016/j.fertnstert.2009.04.038. PMID 19524224.
2 "Soy". University of Maryland Medical Center. Retrieved February 18, 2012.
Shu, X. O.; Zheng, Y.; Cai, H.; Gu, K.; Chen, Z.; Zheng, W.; Lu, W. (2009). "Soy Food Intake and Breast Cancer Survival". JAMA: the Journal of the American Medical Association (American Medical Association) 302 (22): 2437–2443. doi:10.1001/jama.2009.1783. PMC 2874068. PMID 19996398.
Yang, G.; Shu, X. O.; Chow, W. H.; Cai, H.; Li, H.; Zhang, X.; Gao, Y. T.; Zheng, W. (February 2009). "Prospective Cohort Study of Soy Food Intake and Colorectal Cancer Risk in Women". American Journal of Clinical Nutrition (American Society for Nutrition) 89 (2): 577–583. doi:10.3945/ajcn.2008.26742. PMID 19073792.
3 Strom BL, Schinnar R, Ziegler EE, Barnhart KT, Sammel MD, Macones GA, Stallings VA, Drulis JM, Nelson SE, Hanson SA (August 2001). "Exposure to soy-based formula in infancy and endocrinological and reproductive outcomes in young adulthood". JAMA 286 (7): 807–814. doi:10.1001/jama.286.7.807. PMID 11497534.
Giampietro PG, Bruno G, Furcolo G, Casati A, Brunetti E, Spadoni GL, Galli E (February 2004). "Soy protein formulas in children: no hormonal effects in long-term feeding". J. Pediatr. Endocrinol. Metab. 17 (2): 191–196. doi:10.1515/JPEM.2004.17.2.191. PMID 15055353.
Merritt RJ, Jenks BH (May 2004). "Safety of soy-based infant formulas containing isoflavones: the clinical evidence". J. Nutr. 134 (5): 1220S–1224S. PMID 15113975.
Haffejee IE (February 1990). "Cow's milk-based formula, human milk, and soya feeds in acute infantile diarrhea: a therapeutic trial". J. Pediatr. Gastroenterol. Nutr. 10 (2): 193–198. doi:10.1097/00005176-199002000-00009. PMID 2406406.