I decided to consciously lay off soy last week, and I feel strangely better. On an average day, I was drinking a couple of 12 oz. soy lattes, had soy milk on cereal one or two days per week, and was getting the constant dosage of soy oils and flour common to way too much refined food.
It got to a point where a soy latte in the morning would leave me with this weird 'full' feeling for 3-4 hours after drinking it. Okay, so a soy latte has about 8 grams of protein, but it shouldn't affect one like that.
So I was doing a little research tonight. Terra recently had to start avoiding soy in any form due to allergic reactions in the respiratory direction. Mix that with my physical reactions, and I thought it wise to look into it. I did a Google search for 'too much soy' and came up with a very interesting Utne article [http://www.utne.com/2007-07-01/Science-Technology/The-Dark-Side-of-Soy.aspx] which confirmed some of what I already knew, and added more.
Basically, excessive soy consumption (which is unavoidable for those eating a highly refined diet these days, along with corn and wheat) contains a high level of plant estrogens, which mess with your hormone levels and screw up your thyroid (and thus metabolism). Research in Japan shows just one glass of soy milk per day is enough to seriously mess up metabolic processes.
Soy and corn are endemic in most food products because they are CHEAP. Soy derivatives and corn syrup have replaced a diverse range of foodstuffs because we overproduce it, or grow it for one purpose and then have to find something to do with all the 'waste' byproducts. A load of inexpensive 'wheat' bread isn't just wheat anymore, folks. Try buying a chocolate bar with an emulsifier that ISN'T soy lecithin; the local Theo brand and a couple of Trader Joe's bars are about all we've been able to find. Hell, even a proper cake donut may contain soy flour - a couple of years ago I was reading the ingredients label on the cake donut flour used by Countryside Donut House in Northgate and learned this.
Feeling blah and lethargic? It might be what you're eating. While my focus at the moment is soy, the bigger problem is a lack of food diversity. I'm going to be working on that.