the role of Soy (good and bad) in TCM or Taoist medicine

[Non]

I'm interested in finding good sources where soy is mentioned in preferably ancient chinese texts, and its role in medicine And if there are any negative views on it, or if say it's consumed in excess. Specifically in regards to the phytoestrogens contained in them.

 

Could anyone help guide me to a good resource?

 

edit:

 

I saw in the universaltao.com website soy is considered "left-spin" and bad according to this article: http://www.universal-tao.com/article/perfect.html

Edited September 12, 2010 by Non