Docs never understand my thyroid numbers. I'm a clinician myself (non-MD category), and I look at things from the "functional" perspective, so when they say things look fine or that NDT is required to bring things in line, I always question their reasoning.
Back in the early days, I tried .5 grain of NDT on and off, and every time it made me feel worse. It wasn't until I put 2 and 2 together and realized that I had more than enough T4 and that NDT (with its typical 4:1 ratio T4:T3) was overloading the balance.
What does the body do when there is too much T4? It converts it to RT3. And too much RT3 leads to clogged T3 receptors, so even if free T3 looks good, the body feels hypothyroid. The way my labs look are like this:
Free T4: 1.67 ng/dL (0.82-1.77)
Free T3: 3.8 pg/mL (2.0-4.4)
TSH: 3.1 uIU/mL (0.45-4.5)
RT3: 25.2 ng/dL (9.2-24.1)
See what I mean? A good clinician will ask why RT3 is high. Most docs don't even test for it. The most common reason -- high cortisol is slowing down the conversion of T4 > T3 and RT3 is pooling.
The only situation where you want to take straight T3 (without T4) is when this is happening. It's literally the only approach that will clear out that excess RT3. If free T4 is trending with a TSH above 1, then NDT is useful. Be careful, though, if free T4 looks good (as in my case).
It's not a long term strategy if the original cortisol problem isn't fixed. In my case, cortisol was tending to go high because of estrogen. Higher estrogen results in higher reactivity to antigens (think allergies). Allergic reactions tend to raise cortisol. On my labs, eosinophils are always high.... They have finally been coming down because T is going up. As a matter of fact, this allergy season (after starting T therapy), I had no allergic symptoms. None. There is a reason women suffer more from asthma than men, especially during their cycle.
Estrogen effects in allergy and asthma
I have some good news to report, actually --- I think I've found a solution for my high SHBG and lack of response from testosterone. I had a flash of insight last night -- and it occurred to me that by raising testosterone, it's triggered a biofeedback look in the steroid hormone chain to slow down Pregnenolone / DHEA production --- they simply aren't needed when exogenous supply has increased. Then I remembered that my Progesterone has been low on previous labs. Just as an experiment last night, I rubbed a topical solution of Pregnenolone / DHEA onto my forearms (5mg / 5mg) and literally within a couple of hours, I felt completely different. The weak erections immediately disappeared.
So I need to dig a little more in this area. I might try just straight Progesterone and DHEA together, since they would synergistically bring down cortisol -- and that's ultimately what's interfering with both thyroid and testosterone.
It makes you think ... how many men out there have optimal hormone levels but aren't getting the benefits because cortisol is too high? I think it should be mandatory for guys to do a 4-point salivary test before fooling around with other options, especially those that "overtrain". Everyone knows that too much training is catabolic, primarily through excess cortisol.
Bit by bit, this will all become clearer.
If you are curious about the T3 drops I have been using, a lot of the "peptide shops" sell it. You can also do some hunting around the Ray Peat forum, as that crowd seems to be very pro-thyroid (a more is better mentality). But again, don't touch straight T3 if your T4 is going low. You can benefit from NDT instead.
Sounds like you’re very knowledgeable about the thyroid. I’ve been doing a ton of research on the thyroid lately, and it scares me that the level of knowledge you have is more than some endocrinologist with a medical degree. Why they aren’t being taught to test for RT3, I have no idea. But you’re spot on. Straight T3 is what you personally need. Clearly you have enough T4, it’s just converting into RT3. So any exogenous T4 is obviously a bad idea. How some doctors still don’t understand this is beyond me. So in your case, straight T3 is the answer, along with the cofactors iodine and selenium.
So since you’re pretty knowledgeable about the thyroid, I have a quick question. Here are my labs, what do you think is going on. I have average morning temps of 96.1, extreme brain fog, and a bunch of other hypothyroid symptoms. My guess is that my free T3 isn’t getting into the cells, and is pooling in my blood. So my questions are, what do you think is going on, and do you think NDT would help me? I’m thinking a trial of NDT would be the best option, but just curious if you had any insight. Thanks.
T3 total - 83 (76-181)
T4 total - 5.6 (4.5-10.5)
Free T3 - 3.7 (2.3-4.2)
Free t4 - 0.9 (0.8-1.8)
Rt3 - 11 (8-25)
TSH - 0.73 (0.4-4.5)
Thyroglobulin antibodies - (<1)
Thyroid peroxidase antibodies -(1) Range - (<9)
And you’re spot on with guys not paying enough attention to cortisol and DHEA. I see guys on here all the time with low DHEA, that don’t think it’s that important to treat. But it’s literally just as important as testosterone. Plus, like you said, DHEA and cortisol oppose each other. So low DHEA can give you a good idea on where your cortisol sits. I personally have the opposite. Low cortisol and DHEA naturally slightly above the top of the range.