Tired of being Tired, Depressed, Constipated, and Can’t Sleep or Think?

Can anybody hear me

Welcome to TiredThyroid.com, a website for those who are tired all the time, and not getting the help they need to restore their health due to thyroid problems.  This site was specifically written for patients to share with their doctors.  Therefore, it is essential that one understand thyroid physiology terms.  Here, in great oversimplification, are … Read more…

Reverse T3: Side Effects of T3-only (or why you need T4 too)

reverse T3 graphic

High reverse T3 (rT3) is a “bad” thing, according to some, because rT3 “blocks” the receptors, keeping T3 out.  Therefore, high doses of T3 should be taken to “clear” rT3, and because rT3 is made from T4, no T4 should be taken.  I tend to have high reverse T3, did not do well on high … Read more…

Reverse T3 and the “T3-only” protocol

Reverse T3 is a thyroid molecule that is similar to regular T3, except one of the iodine atoms is in a different position.  This makes it inactive.  T3 is the active hormone that the body uses. High reverse T3 (rT3) levels or a “bad” reverse T3 ratio (Free T3 divided by rT3 is less than … Read more…

T3’s negative effect on other hormones

Apparently some people can remain on T3-only indefinitely and actually feel fine, or certainly better than they ever did on T4 medications.  Others, however, become worse, because the high T3 levels have side effects and create imbalances in other hormones.  In men, high T3 levels will cause sex hormone binding globulin (SHBG) to rise, the … Read more…

A reverse T3 ratio greater than 20 does not indicate good health any more than a normal TSH does

Reverse T3, like cholesterol, is a natural substance found in every single body, and has a purpose.  To try and rid oneself of it is unnatural, and analogous to taking statins to bring cholesterol levels down.  Many have suffered permanent damage from taking statins, and people have suffered serious side effects from taking T3-only.  The … Read more…

Reverse T3’s role in the body

Normal, healthy people produce reverse T3, it is not poison, and it is a normal pathway for the breakdown of T4.  It is actually abnormal to have no reverse T3! [7] One purpose of reverse T3 is to reduce metabolism, to prevent starvation in cases of famine.  Anyone on a severe caloric restriction diet will reach a … Read more…

D3, the deiodinase enzyme that makes reverse T3 (NOT Vitamin D3)

Because reverse T3 is elevated when a certain deiodinase enzyme known as D3 is high, a closer look at D3 is warranted.  D3 is the deiodinase enzyme that converts T4 to reverse T3 and inactivates T3 to T2.  Its purpose is to keep T3 levels low.  D3 is absent from most adult tissues, though it is found … Read more…

T4’s role in the body

T4 non-genomic

While T3 appears to be the most metabolically active, all thyroid hormones (T4, T3, T2, T1, T0) have non-genomic effects many are not aware of.  All this means is that they can exert an effect on the cell at the plasma membrane (surface) or cytoplasm level, whereas the primary effects of T3 are at the … Read more…

T3 and T4’s role in the brain

There are two different transporters for T3 and T4 into the brain.  One (OATP1c1) transports only T4, the other (MCT8) transports T3 and T4.  T4 is then converted locally to T3 by the D2 deiodinase enzyme.  The total T3 in the brain comes from what was converted locally (from T4), plus what was transported in … Read more…

T3-only side effects

The problem with T3-only treatment is that one must usually take high doses of T3, which results in T3 levels above the reference range.  These high T3 levels compensate for the lack of T4 in the body.  People on thyroid internet forums that have been on T3-only protocols have reported the following side effects: erythrocytosis … Read more…

Do thyroid receptors really get blocked and take 12 weeks to clear? Is T4 really the problem?

Proponents of T3-only therapy believe that reverse T3 “clogs” the T3 receptors, therefore only T3 should be taken for 12 weeks until the reverse T3 is “cleared.”  Yet others who have not changed their dose to T3-only (and continued to take some T4) have reported reduced reverse T3 levels in subsequent labs, by addressing problems like low … Read more…