Re: Re: the effect of fasting & timing of synthroid on blood test results

[Guest guest]

You have to keep in mind that the tests are checking levels of hormone in the blood, not what is in the body tissues... we're more concerned, actually, with the T4 that is stored in body tissues.... and how well we are converting.. the closest we can get to knowing that is to test the levels of hormone that are free in the blood to get an idea of how much is available for our bodies to use.

Thats why TSH testing alone tells us nothing.... it's making the assumption that the feedback loop with the hypothalamus, pituitary and thyroid are all working properly.. but we know that that can be off in so many instances, due to so many variables... well it just makes TSH not very accurate when trying to fine tune levels.... It can still tell us when things are grossly off... but it's not accurate enough for adjusting meds to optimal levels....

On top of that.... blood levels of the thyroid hormones don't tell us the whole picture either.... you can have high level so both Free T4 and Free T3 and still be hypo... and if you are then you have a good indication that you are having problems with absorption.... Well... won't dig all the way into all of that right now....

Our best indicator as to how we are doing is to check TSH to see if it's reflecting what the thyroid hormone levels are... the Free T4 to see if there is enough for adequate storage and conversion, Free T3, to see if we are converting sufficient levels for good body function.... and then take all of that and relate it to how we feel to be able to figure out where our levels need to be for us to feel well.... not everyone needs the same levels of saturation in the blood to have the correct usage and availability of the hormones and the cellular level of the body.

It's fascinating when you really dig down into this stuff and relate it to how your individual body works......

Topper ()

On Tue, 27 Dec 2005 00:48:25 -0000 "rjane1955" writes:

The question really is how long does synthroid stay in the body. My understanding is it's longer than 24 hrs. So to get it tested before taking the day's dose will measure the continuing level it is at in the body.jane

[Guest guest]

Yes, that's a much better way of saying it.

The question really is how long does synthroid stay in the body. My understanding is it's longer than 24 hrs. So to get it tested before taking the day's dose will measure the continuing level it is at in the body.jane>> Hi, everyone. I'm new here. I was on another site, trying to find out the answer to a question, & someone referred me to this site. Here's my question. Maybe you can direct me to previous discussions on this topic?> > ***> > I've read that if get your blood tested before eating & before taking Synthroid, you'll get a more accurate result -- that is, you can avoid false readings. Does anyone know whether readings taken this way avoid false *high* levels of TSH, or does it avoid false *low* levels of TSH?> > In other words, if a person has her blood drawn *after* eating & taking Synthroid, & her TSH level is shown to be 2.5, are we saying that her TSH is probably actually *higher* or *lower* than 2.5?> > From what I understand, Shomon says that by fasting & not taking Synthroid before a blood test, you can avoid false *low* levels of TSH. (With a false *low* TSH, your doctor would think you're less hypothyroid than you really are.) The medical studies seem to say the opposite, unless I don't comprehend the conclusion of the studies. ???> > Anyone know? What have you heard?> > > > > > ---------------------------------> Yahoo! DSL Something to write home about. Just $16.99/mo. or less

>

[Guest guest]

Yes, that's a much better way of saying it.

The question really is how long does synthroid stay in the body. My understanding is it's longer than 24 hrs. So to get it tested before taking the day's dose will measure the continuing level it is at in the body.jane>> Hi, everyone. I'm new here. I was on another site, trying to find out the answer to a question, & someone referred me to this site. Here's my question. Maybe you can direct me to previous discussions on this topic?> > ***> > I've read that if get your blood tested before eating & before taking Synthroid, you'll get a more accurate result -- that is, you can avoid false readings. Does anyone know whether readings taken this way avoid false *high* levels of TSH, or does it avoid false *low* levels of TSH?> > In other words, if a person has her blood drawn *after* eating & taking Synthroid, & her TSH level is shown to be 2.5, are we saying that her TSH is probably actually *higher* or *lower* than 2.5?> > From what I understand, Shomon says that by fasting & not taking Synthroid before a blood test, you can avoid false *low* levels of TSH. (With a false *low* TSH, your doctor would think you're less hypothyroid than you really are.) The medical studies seem to say the opposite, unless I don't comprehend the conclusion of the studies. ???> > Anyone know? What have you heard?> > > > > > ---------------------------------> Yahoo! DSL Something to write home about. Just $16.99/mo. or less

>

[Guest guest]

Yes, that's a much better way of saying it.

The question really is how long does synthroid stay in the body. My understanding is it's longer than 24 hrs. So to get it tested before taking the day's dose will measure the continuing level it is at in the body.jane>> Hi, everyone. I'm new here. I was on another site, trying to find out the answer to a question, & someone referred me to this site. Here's my question. Maybe you can direct me to previous discussions on this topic?> > ***> > I've read that if get your blood tested before eating & before taking Synthroid, you'll get a more accurate result -- that is, you can avoid false readings. Does anyone know whether readings taken this way avoid false *high* levels of TSH, or does it avoid false *low* levels of TSH?> > In other words, if a person has her blood drawn *after* eating & taking Synthroid, & her TSH level is shown to be 2.5, are we saying that her TSH is probably actually *higher* or *lower* than 2.5?> > From what I understand, Shomon says that by fasting & not taking Synthroid before a blood test, you can avoid false *low* levels of TSH. (With a false *low* TSH, your doctor would think you're less hypothyroid than you really are.) The medical studies seem to say the opposite, unless I don't comprehend the conclusion of the studies. ???> > Anyone know? What have you heard?> > > > > > ---------------------------------> Yahoo! DSL Something to write home about. Just $16.99/mo. or less

>

[Guest guest]

So... are we saying that fasting & not taking Synthroid before being tested will make you seem LESS hypo than you really are? wrote: Yes, that's a much better way of saying it. The question really is how long does synthroid stay in the body. My understanding is it's longer than 24 hrs. So to get it tested before taking the day's dose will measure the continuing level it is at in the body.jane

Yahoo! DSL Something to write home about. Just $16.99/mo. or less

[Guest guest]

No, we're saying that if anything (fasting doesn't have anything at all to do with it, by the way) that not taking Synthroid before being tested will show your body's reaction on the Synthroid dose, instead of the falsely elevated " boost " in your blood stream you'd get just after taking it. Not taking it before being tested would make you appear, by your way of saying it, MORE hypo than if you had taken it then got tested (that would show you LESS hypo because there would be more of the hormone immediately in the blood stream).

Think of it this way. If you just drank a cup of coffee, you'd feel energetic for a little while, then it would wear off. If you could check your caffeine level just after drinking the coffee, it would show higher than it would hours later. Same idea...if you take the synthroid before getting tested, you're going to have a somewhat higher level of it in your body, therefore, appear less hypo at the time.

Though I really don't think it would make that dramatic of a difference overall, I'm sure it does make some.

So... are we saying that fasting & not taking Synthroid before being tested will make you seem LESS hypo than you really are? <

stewlis@...> wrote: Yes, that's a much better way of saying it.

The question really is how long does synthroid stay in the body. My understanding is it's longer than 24 hrs. So to get it tested before taking the day's dose will measure the continuing level it is at in the body.jane

Yahoo! DSL Something to write home about. Just $16.99/mo. or less

[Guest guest]

This is very late answering this, I know, but the one dose of Synthroid that

you took today will not be " gone " out of your body until another week. This

is the nature of T3, since it is the storage hormone, normally slowly

converting to T3 to be used over time. Once it is T3, THEN it is rapidly

used in a 24 to 48 hr period of time. If you are still in a hypo state, if

you are a good converter to T3, then it will convert more rapidly, in order

to compensate for your body doesn't have enough of " desperation " more or

less, of the body to try to get enough to live on. Once the dose has been

brought up to where yours needs to be, then that conversion will slow down

to normal, whatever your normal is, but T4 still won't be disappearing in

two or three days or less. It builds up slowly. That's why we wait around

6 wks for testing again. The actual " action " of T3 is a few hrs, but the

" half life " (or that period of time that it's still in the body) is a day or

two longer.

Re: the effect of fasting & timing of

synthroid on blood test results

> The question really is how long does synthroid stay in the body. My

> understanding is it's longer than 24 hrs. So to get it tested

> before taking the day's dose will measure the continuing level it is

> at in the body.

>

> jane