Advice on low Free T3 results: Looking for advice... - Thyroid UK

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Advice on low Free T3 results

EZM1 profile image
EZM1
12 Replies

Looking for advice please - I had my bloods done last week which included TSH, T4 and free T3 plus a few others.

TSH is 1.21 (0.35 - 3.5 range)

T4 is 14 (8 - 21 range)

Free T3 is 3.5 (3.8 - 6 range)

For the second time my T3 is below the range. My iron and vit d were also low so I’ve been told to take supplements for that. No advice about the T3 though. I currently take Levothyroxine 75mg daily. I don’t know why T3 wasn’t done and just free T3 or what the difference is? I can’t say I’ve been feeling well lately but getting used to that as normal. Any thoughts gratefully received 🙂

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SeasideSusie profile image
SeasideSusieRemembering

EZM1

I don’t know why T3 wasn’t done and just free T3 or what the difference is?

If by T3 you mean Total T3 then it's not a useful test, it's free T3 that tells us what we need to know.

Your current results show that your FT4 is 46% through range. The aim of a treated hypo patient generally is for TSH to be 1 or below with FT4 and FT3 in the upper part of their ranges. You are currently undermedicated and could do with an increase in your Levo to raise your FT4, lower your TSH, and then see where your FT3 lies.

My iron and vit d were also low so I’ve been told to take supplements for that.

Optimal nutrient levels are necessary for thyroid hormone to work properly and good conversion of T4 to T3. What were your results (with reference ranges) and what supplements will you be taking?

Once all nutrient levels are optimal your conversion may be better.

EZM1 profile image
EZM1 in reply to SeasideSusie

Thanks for your reply. I’m currently taking 1000 daily of vit d and trying to take 40 of iron. My b12 and folate levels aren’t okay. I will ask GP if I can increase my levo.

SlowDragon profile image
SlowDragonAdministrator

75mcg is only one step up from starter dose of levothyroxine

The aim of Levothyroxine is to increase the dose slowly in 25mcg steps upwards until TSH is under 2 (many need TSH significantly under one) and most important is that FT4 is in top third of range and FT3 at least half way through range

Your Ft4 is too low and conversion to Ft3 is poor

Improving low vitamin levels can help improve conversion

Low Ft4 shows you need 25mcg dose increase in levothyroxine

NHS guidelines on Levothyroxine including that most patients eventually need somewhere between 100mcg and 200mcg Levothyroxine.

nhs.uk/medicines/levothyrox...

Also what foods to avoid (eg recommended to avoid calcium rich foods at least four hours from taking Levo)

For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested. Also EXTREMELY important to test vitamin D, folate, ferritin and B12

All four vitamins need to be regularly tested and frequently need supplementing to maintain optimal levels

Have you had thyroid antibodies tested?

Low vitamin levels are extremely common, especially if you have autoimmune thyroid disease (Hashimoto's) diagnosed by raised Thyroid antibodies

Ask GP to test B12, folate and thyroid antibodies

You may need to get full Thyroid testing privately as NHS refuses to test TG antibodies if TPO antibodies are negative

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .

Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)

Is this how you do your tests?

Private tests are available. Thousands on here forced to do this as NHS often refuses to test FT3 or antibodies

thyroiduk.org.uk/tuk/testin...

For thyroid including antibodies and vitamins

Medichecks Thyroid plus ultra vitamin or Blue Horizon Thyroid plus eleven are the most popular choice. DIY finger prick test or option to pay extra for private blood draw. Both companies often have special offers, Medichecks usually have offers on Thursdays, Blue Horizon its more random

If you can get GP to test vitamins and antibodies then cheapest option for just TSH, FT4 and FT3 £29 (via NHS private service )

monitormyhealth.org.uk/thyr...

If antibodies are high this is Hashimoto's, (also known by medics here in UK more commonly as autoimmune thyroid disease).

About 90% of all primary hypothyroidism in Uk is due to Hashimoto's.

Low vitamins are especially common with Hashimoto's. Food intolerances are very common too, especially gluten.

So it's important to get TPO and TG thyroid antibodies tested at least once .

Link about thyroid blood tests

thyroiduk.org/tuk/testing/t...

Link about antibodies and Hashimoto's

thyroiduk.org.uk/tuk/about_...

thyroiduk.org.uk/tuk/about_...

List of hypothyroid symptoms

thyroiduk.org.uk/tuk/about_...

EZM1 profile image
EZM1 in reply to SlowDragon

Thanks for your reply, you are very knowledgeable. I have had my antibodies tested soon after my diagnosis when my TSH was 67. They were raised and I’ve been told I do have Hashimotos. My vit D level was 40 (50-120 range) so I’m now taking 1000 daily. My ferritin was 16 (23-300) range. I’m trying to take 40mg daily but usually manage only 20mg. Good information regarding avoiding calcium, I wasn’t aware of that. I’m currently feeling spaced out all the time so will ask my doctor if I can increase my levo dose. I may take in your reply, thanks

SlowDragon profile image
SlowDragonAdministrator in reply to EZM1

TSH is particularly unreliable when we have hashimoto’s as levels hop about all the time

Most important are Ft4 and Ft3

Your Ft4 is only 46% through range. So you need 25mcg dose increase in levothyroxine

Helpful calculator for working out percentage through range

chorobytarczycy.eu/kalkulator

Ft3 is clearly below range ...so you are terrible converter of Ft4 to Ft3

Ft3 needs to be at least half way through range

Hashimoto's affects the gut and leads to low stomach acid and then low vitamin levels

Low vitamin levels affect Thyroid hormone

Poor gut function can lead leaky gut (literally holes in gut wall) this can cause food intolerances. Most common by far is gluten. Dairy is second most common.

According to Izabella Wentz the Thyroid Pharmacist approx 5% with Hashimoto's are coeliac, but over 80% find gluten free diet helps, sometimes significantly. Either due to direct gluten intolerance (no test available) or due to leaky gut and gluten causing molecular mimicry (see Amy Myers link)

Changing to a strictly gluten free diet may help reduce symptoms, help gut heal and slowly lower TPO antibodies

While still eating high gluten diet ask GP for coeliac blood test first or buy test online for under £20, just to rule it out first

Assuming test is negative you can immediately go on strictly gluten free diet

(If test is positive you will need to remain on high gluten diet until endoscopy, maximum 6 weeks wait officially)

Trying gluten free diet for 3-6 months. If no noticeable improvement then reintroduce gluten and see if symptoms get worse

chriskresser.com/the-gluten...

amymyersmd.com/2018/04/3-re...

thyroidpharmacist.com/artic...

drknews.com/changing-your-d...

restartmed.com/hashimotos-g...

How long have you been on 1000iu vitamin D?

With hashimoto’s we frequently need higher dose than average

Suggest you get vitamin D Retested after 2-3 months

vitamindtest.org.uk

What are the actual results of B12 and folate ?

These need to be OPTIMAL...not just somewhere within range

Getting all four vitamins optimal should help improve conversion

Other supplements that may help are selenium and zinc.

You can test levels privately via Medichecks first

Going strictly gluten free may improve gut function too

EZM1 profile image
EZM1 in reply to SlowDragon

Thank you again for your advice. I just read your bio and you have had quite a journey. I was only diagnosed in April last year and am fed up with it so you have done extremely well getting to where you are now. I know I’m not celiac but have read about going gluten free so will try this. I’ve only been taking the vit C for a couple of days. Iron I’ve taken off and on for last year as was diagnosed as anemic which is how this all initially started for me. I have also taken a probiotic as read about good gut health so will try adding them in again. I get dreadful acid reflux which is one of my worst symptoms. I was put on a PPI but stopped this after reading about low stomach acid. Have you ever tried increasing the acid with anything or do you not suffer in this way? My rest heart rate like yours was low 50’s but that has not gone up to average 57/58. I’ll get some of the other vitamins you recommend and hopefully will get an increase of levo from my GP. I don’t want to get the palpitations I got at start again though so hope the increase in dose won’t cause them. Thanks again very much

SlowDragon profile image
SlowDragonAdministrator in reply to EZM1

Many, many people find acid reflux improves on strictly gluten free diet

Obviously getting vitamins optimal and levothyroxine optimal will help

Many people improve low stomach acid by various means. Thousands of posts on here about low stomach acid

healthunlocked.com/search/p...

Suggest you retest vitamin D

Folate, B12 and ferritin need testing too

Lalatoot profile image
Lalatoot

Your levels suggest that you need an increase in levothyroxine.

greygoose profile image
greygoose

I don’t know why T3 wasn’t done and just free T3 or what the difference is?

T3 comes in two forms: bound and unbound. The bound is T3 attached to a protein carrier, which transports the T3 in the blood, but is unavailable for use by the body. The unbound - also called Free T3 - is available for use by the body. So, that's the one we need to know about.

Total T3 is just what it says: the sum total of all T3 in the blood, both bound and unbound. But, the test doesn't tell us how much of each, so is of little use. :)

Jackobee profile image
Jackobee

Would recommend you ask GP for b12 injections as I understand this is needed for good conversion T4 to T3. I have b12 injection every 3 months and feel better for it. You are lucky to get T3 and T4 tested as I am only able to get TSH on the NHS.

EZM1 profile image
EZM1

Thanks for your advice. My doctors are really good but it hasn’t been offered I’ve just requested it, they haven’t said no to be fair though. My B12 levels were okay I think. Did your GP suggest the B12 injections or are you under a consultant?

SlowDragon profile image
SlowDragonAdministrator

Presumably you got your increase in levothyroxine to 100mcg daily

“My B12 levels were okay I think”

You are legally entitled to copies of your results and ranges

Essential to test vitamin D, folate, ferritin and B12 at least annually.....if GP won’t.....get tested privately

We need all four vitamins optimal

Vitamin D at least around 80nmol and around 100nmol maybe better

Serum B12 at least over 500

Active B12 at least over 70

Folate and ferritin at least half way through range

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