Plan of attack for low T3 / Ferritin / B12 - Thyroid UK

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Plan of attack for low T3 / Ferritin / B12


Hi everyone!

My latest NHS results are in:

T4: 17.3 (10-23pmol/L)

TSH: 6 (0.27-4.2mIU/L)

Folate: 10.9 (3.10-20.50ug/L)

B12: 471 (187-883ng/L)

Ferritin: 59 (22-275)

This is in the context of a Medichecks blood test the day before that found low T3 (which the NHS don't check for):

TSH: 5.98 (0.27-4.20)

FT4: 16.74 (12-22)

TT4: 83 (59-154)

FT3: 3.04 (3.1-6.8)

The doctor has raised my Levo from 100mcg to 125mcg to address my symptoms of fatigue and low heart rate. He referred me to a thyroid clinic when I mentioned T3 levels.

That will take a few weeks to come through, and I'm wondering what I should do in the meantime. According to my research, my ferritin is on the low side (should be >100) and likewise my B12 (should be >500).

I'm already taking a Vitamin D supplement daily (25mg), but haven't checked my levels. I don't take a Selenium supplement, nor have I checked those levels.

I'd like to address this ASAP, of course, but I also don't want to mess up anything that might have long term consequences before seeing the endo (which could be ages away!).

I'm thinking a plan of action could be:

- Test Selenium levels with Medichecks before supplementing (because with over-supplementation there's an increased risk of bad things happening to men).

- Start taking B12 supplement and monitor symptoms (because it can't hurt).

- Test T3 and Reverse T3 in a couple of weeks, once the additional 25mcg levo has had time to take effect. This will give me extra ammo for the endocrinologist whenever that happens.

- I have no idea how to raise Ferritin, other than eating liver, which I plan to do once per week.

How does that sound? Any of your suggestions or experiences would be great.

Thank you!


4 Replies

David - ferritin should be half way through it's range. Eating liver once a week will be good, maximum 200g, plus including lots of iron rich foods

You could add an iron tablet if it doesn't cause you any problems, take each one with 1000mg Vit C to aid absorption and help prevent constipation, and take iron four hours away from thyroid meds and any other medication and supplements as it affects their absorption.

You really should test your Vit D level because excess Vit D gets stored and can elevate you to toxicity level if you take more than you need. There are also important cofactors needed when taking Vit D -

When supplementing with B12, a B Complex is also needed to balance all the B vitamins. Go for a decent brand with methylfolate rather than folic acid.

Thanks again Susie! I'm going to go for the biggest Medichecks blood test I can get my hands on - the one that includes rT3 and Vit D as well as the usual. That should give me some answers.

Thanks for the warning!

Gambit62 in reply to ds_charles

your B12 levels are actually quite good - and there is definitely no need to supplement if you aren't symptomatic of B12 deficiency - though I recognise that it will be difficult to evaluate this is if your thyroid isn't under control because of overlap in symptoms.

Serum B12 is a very indirect measure of whether your cells are getting enough B12 - and is really a tool for diagnosing a problem absorbing B12 from your diet. Even in that context, although it will miss 25% of people who are deficient it will also catch 5% of people who aren't B12 deficient but are perfectly okay with levels below the bottom of the normal range and your result is well into the normal range.

Use of high level B12 supplements can cause problems for some people so please think very carefully before going down that root.

This is link to to one of the pinned posts on the PAS forum


ds_charles in reply to Gambit62

Thanks for your wise comment, Gambit. I will be more circumspect!

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