In addition, the thyroid helps to regulate body temperature, hair. growth, joint function, water metabolism, and a host of other functions in the body. Either too much OR too little thyroid can create symptoms, some of them life-. threatening. As with any substance in the body, thyroid has an optimal range, which we.
http://www.drjudithboice.com/info/thyroidfunction.pdf
Board certified endocrinologists are. considering making 3.5 the top of the normal range. Function medicine physicians, those. aiming for optimal function in the body, consider 2.5 the top of the normal range. For those supplementing thyroid, I like to see TSH levels below 1.5. Some people do not. feel completely well until their TSH levels are much lower than the bottom of the usual. “normal” range.
http://www.drjudithboice.com/info/thyroidfunction.pdf
In patients taking T3, the T4 is often extremely low, since the thyroid gland will often shut off production of T4 in this situation. Furthermore, depending on what time a blood test is done in relationship to ingestion of the T3 tablet, the T3 level may range from low to normal to high.
http://www.mythyroid.com/optimalthyroid.html
If TSH levels have been gradually. increasing over time, I know that the thyroid gland has been struggling more and more to. produce enough thyroid hormone. The most likely time for a woman’s thyroid gland to struggle is during major hormonal. transitions: puberty, pregnancy, and peri-menopause and menopause.
http://www.drjudithboice.com/info/thyroidfunction.pdf
Many other diseases can mimic low thyroid function. Testing. •TSH (Thyroid Stimulating Hormone): made by the pituitary, TSH signals the. thyroid gland to produce more thyroid. This is an indirect measure of how well. the thyroid gland is functioning. The higher the TSH level, the more the thyroid. gland is struggling.
http://www.drjudithboice.com/info/thyroidfunction.pdf
An overview of the changes in thyroid hormone levels that occur in depressed patients, and a summary of known studies of T3 and depression may be found in a review article in the journal Thyroid 1998 Oct;8(10):951-6 The thyroid axis and depression.
http://www.mythyroid.com/optimalthyroid.html
Click here for Frequently Asked Questions on Optimal Thyroid Replacement. The majority of patients with hypothyroidism are treated with thyroxine, also known as T4 (Trade names include Synthroid, Eltroxin, Levoxyl etc). Theoretically, pharmacological management of hypothyroidism would mimic what our own thyroid does, which is to produce both T4 and T3. It is important to remember that the majority of thyroid hormone produced and secreted by the thyroid (about 90%) is T4.
http://www.mythyroid.com/optimalthyroid.html
The range of thyrotropin. (TSH), under the impact of placental human chorionic go-. nadotropin (hCG), is decreased throughout pregnancy with. the lower normal TSH level in the ﬁrst trimester being. poorly deﬁned and an upper limit of 2.5 mIU/L.
http://www.thyca.org/download/document/486/PregnancyandPostpartum.pdf
In essence, pregnancy is a stress test for the thyroid, resulting in hy-. pothyroidism in women with limited thyroidal reserve or. iodine deﬁciency, and postpartum thyroiditis in women. with underlying Hashimoto’s disease who were euthyroid. prior to conception.
http://www.thyca.org/download/document/486/PregnancyandPostpartum.pdf
Scott Sullivan,10 and Wilmar Wiersinga11. INTRODUCTION. P. regnancy has a profound impact on the thyroid gland. and thyroid function. The gland increases 10% in size. during pregnancy in iodine-replete countries and by 20%–. 40% in areas of iodine deﬁciency. Production of thyroxine. (T. 4) and triiodothyronine (T. 3) increases by 50%, along with a. 50% increase in the daily iodine requirement.
http://www.thyca.org/download/document/486/PregnancyandPostpartum.pdf
what are functionally optimal thyroid levels during pregnancy
During pregnancy, functionally optimal thyroid levels are 2.5 milli-international units per liter. The  functionally optimal thyroid levels during pregnancy are 2.5 mIU/L.