http://www.physorg.com/news136084675.html
Dr Jorge Chavarro, a research fellow in the department of nutrition at Harvard School of Public Health, Boston, USA, and his colleagues found that men who ate the most soy food had 41 million sperm per millilitre less than men who did not consume soy products. (The "normal" sperm concentration for men ranges between 80-120 million/ml).
see also
http://www.fuckedgaijin.com/forums/showthread.php?t=7145
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