by redgiki on Thu Jan 29, 2009 12:17 am
Soy has a bad reputation due to the presence of phytoestrogens, and the fact that it's simply a by-product of the creation of soybean-based oils. When soy protein forms the bulk of the diet in animals, health problems inevitably result.
But soy as part of a balanced diet including other sources of protein appears to have no counter-indications. It increases thyroid output, which is a big plus for bodybuilders as it's mostly catabolic toward fat. That said, only ten to thirty grams of soy protein per day gives you all the benefits soy has to offer.
As a supplement of perhaps 10%-20% of your protein intake, it's a great option. It cooks up in recipes much, much better than whey and I use it quite a bit for that reason alone. As a replacement for other proteins or sole source of protein, it's a bad choice for a bodybuilder.
--Matt B.