Ahhh, the controversy of soy. There is evidence to support both arguments. Some scientists feel since it is estrogenic (binds to estrogen receptors), soy would stimulate fibroid growth. Others feel it acts as a weak estrogen. Therefore, soy would bind to the receptors, block your estrogen from binding, and be beneficial.
I’ll talk more about that in a minute but I first wanted to list the 5 forms of soy that can be found in my house right now:
tofu (refrigerated, shelf-stable, and dried)
miso paste (white and red)
soy beans (dried)
Yes, I really enjoy soy. My husband thinks there’s something wrong with me because I like the texture of tofu.
Let’s talk a little more about the science since I’m a geek and that’s what I do…
I found a great paper a couple of weeks ago put out by the UK Food Standards Agency . It discusses everything you would ever want to know about soy and phytoestrogens.
This report of the Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment (COT) considers the public health implications of exposure to phytoestrogens in the diet. The report was drafted by a specially convened Working Group of the Committee with the following terms of reference:
To advise on the health implications of dietary phytoestrogens through review of published scientific research and the Food Standards Agency’s phytoestrogen research programme.
The paper is pretty long (A few hundred pages. No, I’m not kidding.) but worth digging through if you’re interested in soy. It’s the most complete report I’ve found so far. Definitely, a geek’s dream!
After reviewing the published scientific data, the group concluded that more studies are needed. There is some evidence emerging in these areas but we need more:
- Just how is soy digested? What is the role of the gut microflora in the metabolism and bioavailability of phytoestrogens?
- How are phytoestrogens absorbed, distributed, metabolized, and excreted (pharmacokinetics)?
- What is involved with the receptor interaction? Estrogen receptors are transcription factors so what’s happening when phytoestrogens bind? Which genes are turned on?
- What else are phytoestrogens doing in the body besides binding to receptors?
Links if you don’t have time for the long paper:
USDA-Iowa State University Database on the Isoflavone Content of Foods
Pretty neat because it allows you to compare the isoflavone (phytoestrogen) content in various foods.
If that link doesn’t work, you can grab the data table here:
USDA-Iowa State University Database on the Isoflavone Content of Foods, Release 1.3 – 2002
(Remember you need Adobe Reader to view the PDF files. It’s a free download.)
Since there are so many questions, I eat soy. It has not caused me problems and I really like the taste. I’m limiting my meat these days so soy and beans are good substitutes for me. Having said this, because there are still so many questions, I understand being cautious.
Tina gave a soy recommendation on the alternative therapy page. At least now I have a guideline for comparison. The soy discussion started on that page so I must thank Jess and Tina. Soy consumption is a hot topic when it comes to fibroids. Hopefully, scientists will conduct more research in this area.