At the risk of getting this wrong from my faulty memory and not having the
references with me at the moment...

Thyroid hormone is circulated within the body in  different active forms,
two that are of
particular interst are commonly referred to as T3 and T4. By far, T4 is the
more active form
of thyroid hormone with respect to metabolism, the more T4 in
circulation, the higher your metabolism.  It has been shown that people on
long term
low carb diets tend to lower their T4 numbers significantly, thus lowering
their metablolism.
This is all a bit simplified, but I think you can see how someone on a low
carb diet with
an interest in losing bodyfat, that this would be undesirable.  (I wouldnt
go as far as
to call it 'bad' tho)

I believe I remember a few on the list with thyroid issues, they may have
more insight
on this.  I believe when you have blood tests for thyroid hormone they
commonly list
both the circulating T3 and T4 numbers.  Body metabolism and the thyroid in
particular
can be a complicated subject and some results can seem counter-intuitive.

  Wade

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Richard Geller said

>What is wrong with T4 dropping over time?