Welcome back to our second post on ‘To
Soy or Not to Soy…”  I would highly
encourage you to read my previous post as you will need that quick update to
make the most out of this post. 

Now, let’s get back to the idea that
soy acts like estrogen.  Our bodies produce three different types of
estrogen: estrone, estradiol and estriol. 
They are called E1, E2 and E3 respectively.  E2 the most powerful
form of estrogen which, when out of balance, can cause or worsen health
challenges from the less severe hot flashes to the more deadly conditions like
breast cancer.  Whole Soy mimics the action of E3 which is a weak
(therefore safer) form of estrogen.  Why is this important?  Well, if
soy mimics a weaker estrogen, then having soy present in the body can be
beneficial.  On the other hand, it is believed that Extracted Soy produces
a ‘stronger’ response than Whole Soy and is, therefore, not recommended in
patients at risk for high estrogen or estrogen-like levels in the body.

Take the instance of a pre-pubescent
girl.  Depending on her diet and family history, she may have an abundance
of E2 (powerful estrogen) circulating in her blood.  Physiology lesson:  All estrogens must bind to an estrogen
receptor that sits on the outside of almost every cell in your body.  Weaker estrogens land on the receptor and
activate the cell when compared to stronger estrogens.  Putting this puzzle together a little more, having
a weaker form of estrogen competing to fill the estrogen receptor can ‘block
out’ some of the stronger forms of estrogen.  In this case, soy is
believed to provide a decreased risk of breast cancer when these girls consume
1-2 servings of whole soy per day. 

Men provide another example of
beneficial use of soy.  Again, having a weaker form of estrogen present in
the blood and binding to receptors will reduce the amount of powerful (E2)
estrogen that can land in those receptor sites (yes, men have estrogen
too!).  Too much E2 is linked to enlarged prostates and also prostate cancer.
 It is believed that taking 1-2 servings of whole soy products
significantly reduces the risk of enlarged prostate and prostate cancer in men.

Wow!  Soy sounds terrific right? 
Well, it certainly can be as outlined in the samples above.  However in the case of post-menopausal women,
we’re a little more cautious.  When a woman is post-menopausal, all of her
forms of estrogen are on the decline.  Even though the rate of this
decline is responsible for all of the sometimes challenging symptoms associated
with ‘going through menopause’, the decline itself is beneficial.  You
see, estrogen is a hormone that tells cells in the body to ‘grow and
multiply’.  As we age, we tend to have more cells that grow and multiply
defectively.  Generally speaking, the body knows what to do with these
cells and they are quickly killed.  But consider too much estrogen present
telling these defective cells to grow and multiply.  There is a chance
that these cells will grow too much before the body can eliminate them. 
These are the beginnings of hormone-related cancers.  

So, going back
to soy….. the natural decline of estrogen with menopause is nature’s way of
reducing the risk of stimulating cell growth.  Said differently, nature is
getting rid of the E2’s in the blood as She knows it’s not a great thing to
have around at this stage in the life cycle. 
Now, let’s say you start eating even the weaker forms of estrogen like
those found in soy, you are eating something that can still cause some level of
estrogen stimulation, albeit weak.  This
weak stimulation could actually be higher than what you would be doing naturally
and without soy intake.  In the end, this
extra estrogen stimulation could cause defective cells to grow and multiply
into cancer, too. 

The above scenarios represent
another aspect of the confusion and controversy over soy.  Again, understanding estrogen physiology…right
here…you get the reason why we cannot rely on a simple ‘Soy is Good’ or ‘Soy is
Bad’ statement.

My final thoughts on soy:  Soy
can be good for some, not so good for others.  It’s beneficial for men,
boys and younger women….not so beneficial for post-menopausal women and always to
be taken in whole, organic form versus extracted form.  I hope the next time you find yourself evaluating
a soy based food, you feel the comfort of science and understanding as you make
the smartest, most individualized choice for yourself or the ones you love.