oops, I did not mean compensatory I meant accompanying conversion problem.
Thanks, I got the link. Also, the "protection" scenario is just one scenario, not necessarily mine. I probably have cellular thyroid hormone resistance with the compensatory T4 to T3 conversion problem.
After going through that link in detail, I think this is the info most pertinent to our discussion.
"Conversely, if the T3 is relatively lower than T4 (i.e., to the left of T4 on the Thyroid Scale™), it means the body is jamming on the metabolic brakes. This can be seen in early Hashimoto’s Thyroiditis where the T4 is high (because of spillage from a damaged thyroid into the blood stream). The body can protect itself from excessive stimulation by converting more of the T4 into RT3 and less of it into T3. Thus, both hormones might be high or above optimal but the T3 will be found to the left of T4 on the scale. (e.g. TSH 0.8, FT4 1.65, FT3 352)"
I can see that theory as one possibility, but I can also question whether your very high FT4 and very low FT3 fits that scenario. Yes, the FT4 is high, but why would your body be "protecting itself from excessive stimulation" by converting so little of the T4 into T3, and, you think, lots more is being converted into rT3? It is an interesting point, but one that is somewhat academic right now, since you will know shortly after testing for the TPO ab and TG ab tests for thyroid antibodies and the test for rT3, along with FT4 and FT3.
Regarding your question about any evidence of low ferritin affecting thyroid metabolism, I have a good link for you that discusses that and more, and also provides numerous references to supporting scientific studies. I cannot post here on the Forum, but will send in a PM.
First, here is the link you requested: http://www.drrind.com/therapies/thyroid-scale
Second: I have a lot going on. Ferritin level has been very low in the past (as low as 8 and recently 102 but most recently 52 - not checked because of thyroid), but not low now because of supplementation. However, correcting symptoms does not usually really get to the heart of the problem. Meaning, just because my ferritin level is no longer low, does not particularly mean anything. Also to my knowledge, cause and affect as opposed to correlation has not been shown. So, it's possible that whatever causes low ferritin, causes thyroid issues or that thyroid issues causes low ferritin or that low ferritin causes thyroid issues. Anyway, normalizing my ferritin by supplementation has not really resulted resolution of any thyroid symptoms. If I do have a selenium deficiency, then it almost has to be some type of resistance because not only do I consume foods high in the element (just by coincidence) I also take selenium supplements (133 mcg/day) as part of a multivitamin also by coincidence. I also have some other autoimmune issues.
To confirm or rule out Hshi's, both TPO ab and TG ab should be run. Cases that we run across, where the patient has high FT4 and relatively low FT3, are usually related to poor conversion of T4 to T3, as opposed to over conversion to RT3. Poor conversion can be associated with low levels of ferritin and selenium, among other things. Have never seen info suggesting that it could be associated with early Hashi's, but always willing to learn new things. Do you have a link to that info?
From what you have said, I'm sure you are prepared to request tests for FT3, FT4,and rT3. Tests for TPO ab and TG ab will confirm or rule out Hashi's. Since hypo patients are frequently too low in the range for Vitamin D, B12 and ferritin, I suggest those, along with selenium.
Hi, I thought I was asking a question of Dr. Lupo - but no matter. Range for FT4 is .8-1.7; I am at 1.8. Range for FT3 is 2.2-4.4; I am at 2.5. The point here is High T4 to T3 ratio or a high r-T3 (a rare test but we can est. from these #'s that it's probably high) are suggestive of peripheral cellular resistance as these levels indicate a decreased conversion of T4 to T3. In addition, this is a sign of early Hashi. TPO anti is 14; scale 0-34. And no, I am not on any thyroid medications. I have a follow up with my endo on Thu and wanted to get out in front before I see her. Seems futile to e to begin taking T4.
Please post the ranges you mention for the Free T4 and Free T3.
Having hypothyroid symptoms means it is likely that Hashimoto's Thyroiditis is involved, since Hashi's is the most common cause for diagnosed hypothyroidism. You can find out for sure by testing for the thyroid antibodies associated with Hashi's which are the TPO ab and TG ab tests.
Are you currently taking thyroid meds? If so, which brand and dosage?