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I have normal Iron but low Ferritin, can this still cause conversion problem T4 to T3?


Just wondered if anyone knows if this can still cause a problem with converting

T4 to T3 My Iron is 19umol/L range 6.6 - 26, Transferrin saturation is 28%

range 20 - 55 and Ferritin 50ug/L range 13 - 150.

If it does how do I increase the Ferritin without increasing the Iron,

as I have know idea what to do. I know high Iron isn't good so I am worried about taking too much.

Any help would be great.


12 Replies

This explains all three as you scroll down optimal values.



Thanks Heloise, I will have a look and take it from there.


You are welcome TJ. I'll just add that my last ferritin test came out to 151 and was over the highest range. But as it says in the article, this could just denote a lot of inflammation but I did read that vitamin C will also cause higher ferritin and I do take ascorbic acid crystals in a fruit drink. I also snack on nuts which also raise ferritin. Maybe you could try those to see if it makes a difference.

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That is high isn't it, as for the vitamin C I do take 3 grams a day, so I'm surprised

my ferritin isn't higher. I didn't know about the nuts, I will try them although I'm not

a fan, but I'll try anything. Glad it works for you. Thanks again:-)


My iron is in range but I have low ferritin levels - it is called hypoferritinemia - and since I have been on iron supplements given to me by my endo and gastro (ferrous sulphate 200mg twice daily) I have had to reduce my levo twice due to going over medicated, so my body is definitely using my levo a lot better.

So in answer to your questions, yes in can cause problems with conversion - I felt dreadful with low ferritin but am now almost back to my pre-hypo days.

Moggie x


Hi Moggie,

I didn't know it was called that, I'm glad the ferrous sulphate is working for you. I

have been taking an iron supplement made by Mineral Check, it only has 14mg

Iron, so I also take a Spatone sachet, which is only 5mg, it just isn't enough.

My Gp doesn't think there is a problem though, so I will have to do see if I can

get it somewhere.

I do think this could have been the cause of my problems, I have tried everything else and

still feel tired and hypo, but can't raise my meds, I really hope this is the answer.

Thanks for your help:-)


Ferrous Sulphate 200mg's contains 65mg's of iron - so I am on 130mg's of iron daily - I doubt your levels will rise at all with the amount of iron you are taking. It's taken me a whole year of 200mcg's to get my levels up from 12 to 64 so my gastro decided to double the dose.

Change your iron supplements to ferrous sulphate (£1.40p for 28) and take with vitc and food and your levels should start to rise.

Moggie x


Yes you're right, looking at the amount you are taking no wonder I still

don't feel well. What level is your gastro aiming for? I've seen that it

should be about 70-90.

I'll change my supplements and see what happens, fingers crossed.

Thanks again:-)


Seeing as my levels had gone up to 64 (not far off of the magic 70) I was surprised when she doubled the dose. Especially after I had told her that I had a metallic taste in my mouth only a few weeks previous (this can be the bodies own way of telling you that your iron could possible be getting to high). I had to stop the iron for a couple of months due to test she wanted to do and an operation to remove my ovaries but started back on the double dose early last month and so far so good - no metallic taste as yet.

She wants me to stay on this dose for 3 months and then re-test.

Hope that has given you some idea of what a long haul you are in for, and that's on the ferrous sulphate, I think you would have been taking your iron meds for life and still gotten nowhere on the level you have been taking.

Moggie x


It's amazing how long it takes, I thought it would only take a couple of months,

but I suppose as long as you get there in the end that's what matters and I'm glad

you are nearly there. I thought it was about 70, so I will get some tablets and aim for that.

I was just a bit worried about taking too much iron, as I know it can be harmful, but as

long as I re-test it should be fine.

I have been taking my supplements for 5 years now, so you're right, they are doing

nothing for me, I just wish I knew about the ferritin test years ago, I could be well now.

Never mind I feel better just knowing that I'm not going mad, there is something I can


Thanks again, take care x


Your welcome and now you have a posh name for your low ferritin as well to impress people with.lol.

Just be aware of the metallic taste and try and have regular blood tests - mine are done every 4 months.

This link explain about ferritin and conversion.


Good luck with it.

Moggie x


That's great, you have been very helpful:-)

I will let you know how I get on and good luck to you too!

I hope things keep improving for you.

Take care x


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