T4 to T3 conversion problem?: Hello all. I wanted... - Thyroid UK

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T4 to T3 conversion problem?

CraftyGamer19 profile image
17 Replies

Hello all. I wanted to ask for interpretations of my recent thyroid lab results. With some context, the last 2 labs I had done, one in December and one just a few days ago in March, showed that I had very low TSH. I have Hashimoto's and this was very strange to me because it would indicate I am over medicating with levothyroxine, though I still have all the telltale signs of hypothyroidism - I'm always cold, fatigued, have dry skin, etc. My TSH in December was 0.109 uIU/mL (the range in 0.45-4.5), so I decreased my medication slightly to try to get the labs better but not feel too hypothyroid. After having been on the new dose for 2 months I got my tests done again and now my TSH is even lower! - 0.079, even though I hace worse hypothyroid symptoms than I had before the dose decrease.

My endocrinologist only tests TSH and Ft4, which is what I had done in December, so this time I went to my primary doctor to have a full thyroid panel done.

Most recent test results:

TSH: 0.079uIU/mL (0.45-4.5 reference)

T4: 10.3ug/dL (4.5-12 reference)

Free T4: 1.74ng/dL (0.82-1.77 reference)

T3: 99ng/dL (71-180 reference)

I do not know why she didn't test free T3 but I can't go back to get more tests done so this is what I have.

From what I have read, you want total T3 to be in the upper 30% of the reference range to be considered optimal and most people with Hashimoto's have symptoms if it is any lower than that. My total T3 is significantly lower than that; it is in the lower 30% of the reference range. But my FT4 and T4 are on the high end of their reference ranges.

So I'm wondering, could the reason I have hypothyroid symptoms be because my body is having trouble converting T4 to T3 even though my TSH is so low? And also, what does TSH react to - T4 levels or T3 levels? Is my TSH low because my pituitary is reacting to my high T4 and ignoring my lower T3 levels?

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17 Replies
SlowDragon profile image
SlowDragonAdministrator

You need vitamin D, folate, B12 and ferritin tested

What vitamin supplements are you currently taking

Are you on strictly gluten free diet and dairy free diet

If not always worth trying both/either

CraftyGamer19 profile image
CraftyGamer19 in reply to SlowDragon

I can't get those things tested. I live in the US and my doctor likely won't see the need to test those things, not to mention it is expensive. I am not taking any supplements but I usually eat pretty well as far as vitamin intake goes, and I avoid gluten and dairy when possible, though I usually have small amounts of each every day.

SlowDragon profile image
SlowDragonAdministrator in reply to CraftyGamer19

Being almost gluten free is a waste of time

To be effective it needs to be absolutely gluten free

Dairy is possibly less critical.

As Jaydee1507 has explained, how good our diet is has little effect if not absorbing nutrients in the gut

Many, many members find they need to supplement continuously to maintain GOOD vitamins

usually vitamin D and vitamin B complex, sometimes separate B12 as well (initially if not ongoing)

And possibly iron rich diet to maintain optimal ferritin levels

Test once year minimum, vitamin D, folate, B12 and ferritin

buddy99 profile image
buddy99 in reply to CraftyGamer19

Have you looked into letsgetchecked for blood tests (D, folate,B12). I used to take advantage of their services while they were available in Canada (same issue with doctors limiting testing). While the company does not operate in Canada anymore, they are still available in the US. I don't know whether the pricing is affordable, but it should be easy to figure out when you go to their website, if you are interested.

Jaydee1507 profile image
Jaydee1507Administrator

Did you get your vitamin levels tested? They are really important for us to be able to use our thyroid hormone properly and to help with symptoms.

Previous post here. healthunlocked.com/thyroidu...

CraftyGamer19 profile image
CraftyGamer19 in reply to Jaydee1507

I have gotten a couple tested in the past and they were in the reference ranges, but I cannot get them tested again. But as far as the lab tests I do have, do you think I am having a conversion problem?

Jaydee1507 profile image
Jaydee1507Administrator in reply to CraftyGamer19

Is that a total FT3? We need to see a Free T3 plus vitamin levels to be able to tell.

Good diet means little with vitamin levels when hypothyroid. We get low stomach acid and cannot absorb vitamins well from food. People doing well will be continuously supplementing to get their levels OPTIMAL.

Here is justone company in the US that offers testing privately. That or ask your Endo etc personalabs.com/keyword/pri...

Low vitamins will mean low TSH.

Catseyes235 profile image
Catseyes235

my TSH has been around 0.1 for over 20 years. My doctor asked how I if felt (VER Y IMPORTANT). I felt fine and was happily ish on 150 mcg Levo but a newish doc 4 years ago freaked out that I was overtreated ...I wasn’t and hypo symptoms increased as I obligingly reduced to 125 Mcg then 100. My cholesterol and blood pressure increased and I had a mini stroke. Eventually I asked to see and endo who added T3 to my treatment and bingo no more freezing extremities, hair falling out, dry skin and fatigue.

I was taking antacids and Omeprazole which they discovered can prevent T4 conversion. I tweaked diet to have absolutely no processed foods, never anything with white flour and sugar and biggest change was to start having sourdough bread. Took a while to get dosage right and sometimes add in extra T4 but so much better now. TSH is probably only a good indicator for normal healthy people? Good luck!

CraftyGamer19 profile image
CraftyGamer19 in reply to Catseyes235

Thank you! That's very helpful. I will see a new endocrinologist soon and I will ask her about adding T3 or trying NDT

jrbarnes profile image
jrbarnes

I'm in Texas and use UltaLab. If you're in a state that allows, you can buy all these tests online and go to the Quest lab. I use this rather than waiting for my Dr and they always run sales on lab tests. They email my results as quick as the next day. My Total T3 is always in the 80s on Levo. It does increase the more T3 I add. 10mcg bumped it up to 105 but if I wanted to get it up to the top 30% I'd have to take quite a bit but that wouldn't necessarily make me feel better. I wouldn't focus so much on the numbers but how you feel. I will never go to an endocrinologist again for my thyroid. Better to seek out a Dr that mentions T3 or "hormones" on their website, even an obgyn. I currently see a registered nurse at a functional health clinic. She also has hypo so she understands her patients. I pay $99 every 6 months to see her and she responds quickly to emails. I've been to several different types of Drs and endos have been the laziest when it came to my treatment so I finally went the functional route. I'm on the opposite end. When my FT4 was 1.7 my TSH was 1.8. Even at 1.9 it was still on the higher end. You can't decide a dose based upon the TSH. I add 10mcg T3 to my Levo and my TSH drops to 0.19.

CraftyGamer19 profile image
CraftyGamer19 in reply to jrbarnes

Yeah I'm very fed up with doctors, but I don't know how to find a better one except for trial and error. They don't usually have websites that explain how they treat patients and I can't exactly call them up and ask. It is very tempting to go the functional medicine route but that is way more expensive than any doctor's visit and they won't take insurance. Personally, I don't see why I need an endocrinologist or a doctor at all. I can understand my own labs well enough and how to adjust my medication based on those labs and how I feel, but I have to have a doctor to prescribe my medication. The system is just very screwed up.

jrbarnes profile image
jrbarnes in reply to CraftyGamer19

Traditional doctors don't have websites explaining how they treat patients but the ones who focus and place importance on hormones and wellness will say so. You have to pay attention to the verbage they use on their website. Also you need to read the reviews that people are saying about the doctor which will support that they are open-minded. I've probably seen about 10 different doctors in 10 years and spent like 5000 times more going with the traditional doctor on insurance than I have ever spent on this nurse I see at the functional clinic. Not all functional clinics are the same. I went to another one prior to this and didn't like them, so it is trial and error. I went to an OBGYN on my insurance who was really nice and prescribed natural desiccated and T3 for me but doctors on the insurance model don't have enough time for you. You can order thyroid meds online. You can private message me for a couple of reliable websites if you need it. I adjust my meds however I want because you can't rely on doctors to figure it out for you. Focus on what you can do One small step at a time and try not to get overwhelmed. There was a time when I felt so overwhelmed by The thought of having to look for another doctor, read through their websites, read through reviews etc but I think when you finally find a doctor that is willing to prescribe for you without hassle it will pay off.

You could test for the DIO2 genetic mutation which causes less than optimal conversion of T4 to T3. I tested in the UK which showed I have the mutation. My TSH and T4 levels were in the normal range but I felt hypo. I take T3 and feel much better. The DIO2 result is useful evidence for my doctor.

Vvaughn profile image
Vvaughn

In the U.S. you can use Jason Labs. {Jason health.com) You can order whatever tests you want without a prescription. They are very reasonable. Lab choices are plentiful. Go check out their website.

Batty1 profile image
Batty1 in reply to Vvaughn

I have not and will check them out… thanks

Batty1 profile image
Batty1

You can pay for your own thyroid labs (FT3) by ordering it through walkin labs (but this depends on where your located) it’s $58.00 where Im located …. Your right for some reason doctors here see no need for vitamin testing I just went through this myself with Vitamin D testing my doctor eventually gave in and ordered it we just shouldn’t have to battle for vitamin panels…

jrbarnes profile image
jrbarnes in reply to Batty1

Have you tried Ulta Lab? I used to do Walk-in lab until my doctor told me how much cheaper Ulta was. I got a panel with vitamin B12, folate and vitamin d for only $67 after a 20% discount. The vitamin d alone is $39 on Ulta. They only do quest diagnostics through Ulta so I don't know if it's available where you are but I like this company because they are always giving big discounts.

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