Read all of Rutz’s columns on soy for the whole story:

Soy is making kids ‘gay’
The trouble with soy – part 2
The trouble with soy – part 3
The trouble with soy – part 4
The trouble with soy – part 5

For many people, the most shocking new revelations about soy are not the increased risks of breast and other cancers [1-2], the link to childhood leukemia [3-6], the failure to prevent heart disease [7-8], infertility [9-10], or thyroid damage, with its symptoms of weight gain, fatigue and depression [11-13]. What really startles many of us is soy’s impact on male sex organs, estrogen overload, testosterone suppression, and premature female puberty [14].

The root sex problem is that soy is loaded with isoflavones, plant estrogens that operate like human female estrogen, which occurs naturally in our bodies, male and female. These “phytoestrogens” cause serious developmental problems. They’re only 1/1,000th to 1/1,200th the potency of human estrogen, ounce for ounce, but it’s common for babies to consume them in such large quantities that they overwhelm their bodies’ delicate testosterone-estrogen balance, leaving their victim – male or female – with a wild variety of lifelong symptoms, sometimes even disfigurement [15-19].

Toxicologists estimate that an infant fed exclusively on soy formula is getting the equivalent of three to five birth control pills ? per day [20]. One study found that soy-fed babies had 13,000 to 22,000 times more estrogen in their blood than milk-fed babies [21].

These are not just curious, isolated data. One percent of U.S. girls are now growing breasts or pubic hair before age three. By age eight, either of these two abnormalities is appearing among 14.7 percent of white girls and a staggering 48.3 percent of black girls [22]. Why so many black girls? Probably because they are more likely to be given soy infant formula. They are being robbed of their girlhood. Soy formula-fed girls are also more likely to have lifelong menstrual problems (primarily longer and more painful periods), hormonal changes associated with infertility, and other health problems. If this isn’t a national medical emergency, I don’t know what is.

The situation is just as bad for boys. Boy babies fed soy formula may go into puberty late ? or not at all. Some of these boys are so feminized that their breasts grow but their penises don’t. Some mature into adults with penises not much bigger than the ones they were born with! Others might look normal and go through puberty on time, but can’t father children because their sperm are too few in number (or poor swimmers and/or unable to fertilize eggs) [23]. Sperm counts dropped 50 percent between 1939 and 1990 and are continuing to go down at the rate of 2 percent per year [24]. (Another national emergency.) Men make sperm throughout their lives, of course, but production ability can be seriously hurt by soy during the first trimester of pregnancy, during infancy, and early childhood [24-25].

It’s not just the sex organs that are affected during the key developmental phases of pregnancy and infancy. The brain, too, can be irrevocably changed by excess estrogens, which suppress testosterone. That may contribute to altered sexual behavior and sexual preference. Estrogenized males of many species are more likely to suffer from ADD/ADHD and even to perform more like females on tests [26-28].

Soy won’t hurt a grown man the same way. It’s apt to flatten his libido, but won’t affect the size or shape of his sex organs. (Against my better judgment, I took a national TV interview last week. They handed a bowl of soy stuff to a guy in the studio audience. After he had munched for thirty seconds, the host asked him, “Well, you startin’ to feel kinda swishy yet?” Good comedy, but highly misleading.)

However, soy can cause gynecomastia (female-looking breasts) within months. A recent study at the University of North Carolina at Chapel Hill showed that men eating whopping amounts of soy experienced breast enlargement and even some nipple discharge [29]. They ate a lot more soy than most of us would, but it serves as fair warning.

Moms eating soy during pregnancy are putting their babies at risk because isoflavones swim right through the placenta [30-31]. This can mess up hormonal balance, especially during the first three months, when male fetuses are in a crucial developmental stage and absolutely must have adequate testosterone. Those that get plant estrogens instead of mom’s testosterone are at risk for birth defects like cryptorchidism (undescended testicles) and/or hypospadias, in which the opening of the penis is underneath instead of at the tip [32]. Although undescended testicles can be corrected fairly easily through surgery, hypospadias is far more serious. In worst case scenarios, it can require as many as 10 separate operations. Even then, the boy may not grow up to be an adult male with full sexual function. His penis typically never gets longer than one and a half inches [33].

Hypospadias is on the rise in the U.S. and Europe, and now occurs in one out of 125 births [34]. This coincides with the greater numbers of industrial chemicals in the environment, but also with the growing popularity of vegetarian and vegan diets. A British study in 2000 showed that vegetarian mothers are five times more likely to give birth to a boy with hypospadias than mothers who eat a varied diet [35]. Sadly, vegan moms-to-be think they are eating healthfully when they swig soy milk, nosh on soy nuts, and eat veggie burgers. The tragic result can be undescended testicles, hypospadias or even homosexuality. No study says that soy dooms a child to homosexuality, but it’s not hard to believe that at some point during pregnancy babies are hardwired for sexual preference. (See the Psychological Medicine article in endnote 27 below.)

Pediatricians are seeing so many over-estrogenized boys today with breasts, delayed puberty and /or behavioral problems that they’ve come up with the terms “Developmental Estrogenization Syndrome” and “Testicular Dysgenesis Syndrome” [36].

Right now, no evidence indicates that soy during childhood or adulthood is likely to change sexual preference. The danger zone is the first three months of both pregnancy and infancy, when male physiology and brain circuitry are still developing. In other words, a girl-chasing, football-playing college boy won’t go gay even if he becomes a vegetarian or snacks all day on soy energy bars. (He might develop thyroid or other health problems or lose most of his libido, though.)

My larger concern is that the increasing number of less robust 15-year-olds who are already “struggling with their sexual identity” will be shoved over that thin line into homosexuality. No, they won’t wake up some morning with floppy wrists and a nasal lisp, but they may begin to gravitate toward social circles where they feel more comfortable ? and less expected to be rowdy or brag about a string of sexual conquests. And once a teen is ensconced in a homosexual milieu, breaking free from it could mean abandoning his best friends.

Does the idea that soy can cause so much trouble sound like Rutz sensationalism? Don’t just take my word for it. Here’s what government health experts in Israel and France have decided: The Israeli Health Ministry has looked long and hard at the evidence and concluded that its citizens won’t “be fruitful and multiply” if they eat too much soy. It has warned that babies should not receive any soy formula, that children to age 18 should not eat soy more than once a day (to a maximum of 3 times a week), and that adults should beware because of breast cancer and adverse effects on fertility [37].

The French, meanwhile, intend to maintain their reputation as ardent lovers. Food manufacturers in France will soon have to remove those dangerous plant estrogens from soy formula and to put warning labels on soyfoods and soy milk. French Food Agency experts see the biggest risks as being to children under three and women who have been diagnosed with or have breast cancer in their families [38]. The British Dietetic Association also warns parents to avoid soy formula [39].

Lots of Americans accept everything our FDA and NIH say as gospel. Those poor souls are now in danger because their trusted government watchdogs have yet to bark any warnings about soy. However, Daniel Sheehan, PhD, one of the FDA’s top toxicologists, has warned that that infants fed soy-based formulas have been placed at risk in a “large, uncontrolled and basically unmonitored human infant experiment.”

Do you really want to put your child into that experiment?

Next week: More news about soy ? all documented, all bad.

  1. Fallon, S, Daniel KT, Sanda W. Responses to Docket 2004Q-0151 Solae Company Health Claim on Cancer. Documents submitted to the FDA, June 14, 2004, January 20, 2005 and April 11, 2005. Posted at under “Soy Alert.”

  2. Daniel, Kaayla T. The Whole Soy Story: The Dark Side of America’s Favorite Health Food (New Trends, 2004).379-394. Overview of how soy can cause, contribute to or accelerate the growth of cancers, including 131 references. Includes about 200 real-life horror stories that will make you run screaming into the kitchen and toss out anything with soy on the label!

  3. Strick R, Strissel PL et al. Dietary bioflavonids induce cleavage in the MLL gene and may contribute to infant leukemia. Proc Natl Acad Sci USA, 2000, 25,97, 9, 4790-95.

  4. Editorial. Infantile leukemia and soybeans – a hypothesis. Leukemia, 1999, 13, 317-20.

  5. Ross JA, Potter JD et al. Maternal exposure to potential inhibitors of DNA topoisomerase II and infant leukemia (United States) a report from the Children’s Cancer Group, Cancer Causes Control, 1996,7, 581-590.

  6. Hengstler JG, Helmerdingert CK et al. Dietary topoisomerase II- poisons: contribution of soy products to leukemia? EXCL J, 2002, 1, 8-14.

  7. Sacks FM, Lichtenstien A et al. Soy protein, isoflavones and cardiovascular health: an American Heart Association Science Advisory for professionals from the nutrition committee. Circulation, 2006, Feb 21, 113, 7, 1034-44. Epub Jan 17, 2006.

  8. Stauffer BL, Konhilas JP et al. Soy diet worsens heart disease in mice. J Clin Invest, 2006, Jan, 116, 1, 209-16.

  9. Daniel op cit. 357-78. Overview of soy and infertility with 103 references.

  10. Jefferson WN, Padilla-Banks E, Newbold RR. Adverse effects on female development and reproduction in CD-1 mice following neonatal exposure to the phytoestrogen genistein at environmentally relevant doses. Biol Reprod, 2005, Oct; 73, 4, 798-806. Epub June 1, 2005. A recent, well-designed National Institute of Environmental Health Sciences study.

  11. Daniel, Kaayla T. op cit, 311-330. Comprehensive overview of the scientific literature on soy and thyroid disease with 80 references.

  12. Ishizuki Y, Hirooka et al. The effects on the thyroid gland of soybeans administered experimentally in healthy subjects. Nippon Naibundi Gakkai Zasshi, 1991, 67, 622-629. Translation by Japan Communication Service, Wellington, NZ.

  13. Divi RL, Chang HC, Doerge DR. Antithyroid isoflavones from soybean. Biochem Pharmacol, 1997, 54, 1087-1096.

  14. Daniel, Kaayla T. op cit, 331–378. Overview of the scientific literature on the effects of soy formula and soy foods on male and female reproductive system development with 201 references.

  15. Ibid. 295-309 and 331-378.

  16. Franke, AA, Custer LG et al. Quantification of phytoestrogens in legumes by HPLC. J Agric Food Chem, 1994, 42, 1905-13.

  17. Markiewicz J, Garey J et al. In vitro bioassays of non-steroidal phytoestrogens. J Steroids Biochem Mol Biol, 1993, 45, 5, 399-405.

  18. Irvine CHG, Fitzpatrick MG, Alexander SL. Phytoestrogens in soy-based infant foods: concentrations, daily intake and possible biological effects. Proc Soc Exp Biol Med, 1998, 217, 247-253.

  19. Setchell KDR, Zimmer-Nechemias L et al. Exposure of infants to phyto-oestrogens from soy-based infant formula. Lancet, 1997, 350, 9070.

  20. Office of the Swiss Federal Health Service Bulletin #28, July 20, 1992.

  21. Setchell KDR, Zimmer-Nechemias L et al. Isoflavone content of infant formulas and the metabolic fate of these phytoestrogens in early life. Am J Clin Nutr, 1998, 69 (suppl) 1453S-61S.

  22. Giddens, Herman et al. Secondary sexual characteristics and menses in young girls seen in office practice. Study from the Pediatric Research in Office Settings Network, 1997, 99, 4, 505-512.

  23. Daniel, Kaayla. op cit. 332-339, 365-374.

  24. Sharpe R, Shakkeback N. Are oestrogens involved in falling sperm counts and disorders of the male reproductive tract? Lancet, 1993, 341, 1292-1345.

  25. Auger J, Kunstmann J et al. Decline in semen quality among fertile men in Paris during the past 20 years. NEJM, 1995, 332, 5, 281-85.

  26. Hines M. Hormonal and neural correlates of sex-typed behavioral development in human beings. In Marc Haug, ed. The Development of Sex Differences and Similarities in Behavior (Dordrecht, Kluwer Academic, 1993). 131-147.

  27. Harrison PJ, Everall IP et al. Is homosexuality hardwired? Sexual orientation and brain structure. Psych Med, 1994, 24, 811-16.

  28. Lund TD, West TW et al. Visual spatial memory is enhanced in female rats BMC Neurosci, 2001, 1, 1-13.

  29. Squires, Sally. Nutrition not for women only. Boys and men can benefit from soy too. Washington Post, June 8, 2004. Hard to believe, but the Washington Post diet columnist gave this a positive spin despite the report of breast enlargement, nipple discharge, and lowered testosterone!

  30. Foster WG, Chan S et al. Detection of phytoestrogens in samples of second trimester amniotic fluid. Toxicol Letter, 2004, 129, 3, 199-205.

  31. Doerge DR, Churchwell MI et al. Placental transfer of the soy isoflavone genistein following dietary and gavage administration to Sprague Dawley rats. Reprod Toxicol 2001, 15, 2, 105-10.

  32. Daniel, Kaayla. op cit, 370-374. Overview of male fetal development, hormonal needs, endocrine disruption caused by soy backed by numerous scientific references, including textbooks.

  33. Baskin, Laurence, ed. Hypospadias and Genital Development, Advances in Experimental Biology and Medicine, vol 545. (N.Y. Kluwer Academic/Plenum Publishers, 2004. The definitive textbook.

  34. Ibid.

  35. North K, Golding J. A maternal diet in pregnancy is associated with hypospadias. BJU Int, 2000, 35, 107-13.

  36. Baskin, op cit.

  37. Siegel-Itzkovich J. Health committee warns of potential dangers of soya. BMJ, 2005, July 30, 331, 7511, 254.

  38. Press Release, AFSSA (Agence Francaise de Securite Sanitaire des Aliments (French Food Safety Agency), March 9, 2005,Translation available online at

  39. British Dietetic Association. Paediatric group position statement on the use of soya protein for infants. J Fam Health Care, 2003, 13, 4, 93.

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