Ferritin Low: How much Iron do you take and wha... - Thyroid UK

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Ferritin Low: How much Iron do you take and what form?

Hi all,

My partner has changed to NDT (Armour) from Levothyroxine. This is looking pretty good so far - however one thing we wanted to make sure we had right is his ferritin level.

Last blood test this was 40, range 30-400 ug/L. His endo said that this was "fine", but we promptly ignored her and he started taking ferrograd C. This contains two active ingredients; ferrous sulphate, which is a form of iron and ascorbic acid, which is vitamin C. Exact amounts are 325mg (equivalent to 105mg elemental iron) in a prolonged release formulation and Vitamin C (equivalent to 500mg Ascorbic acid)

For people who had low ferritin before - how much iron did you take and what form? Is what he is taking enough? The Ferrograd is just something I grabbed from Boots so wasn't a very informed choice.

Thanks so much in advance - your advice is so valuable to us

27 Replies

Ferrograd C isn't a good choice of iron supplement. It is a modified release preparation which means that the iron in it is released slowly as it passes through the gut. The problem is that the gut can only absorb iron over a short piece of intestine. So the pill could sail past that bit of the gut and the rest gets "wasted".

The British National Formulary (BNF) has a comment on this problem :



Modified-release preparations

Modified-release preparations of iron are licensed for once-daily dosage, but have no therapeutic advantage and should not be used. These preparations are formulated to release iron gradually; the low incidence of side-effects may reflect the small amounts of iron available for absorption as the iron is carried past the first part of the duodenum into an area of the gut where absorption may be poor.

End Quote

It is worth reading the whole page and the various sub-sections.

As you can see from that page there are various forms of iron supplement. Iron is poorly tolerated by many people so some experimentation may be required.

I've been taking prescription strength iron supplements for about 18 months now. I absorb iron very badly because of a poorly functioning gut. But for people who absorb it normally it should be possible to fix a deficit within 3 - 6 months.

The ones that I take are :

Ferrous fumarate 210mg, bought in boxes of 84 - this is sufficient for dosing three times per day for 28 days. When I last bought it it cost just over £4 per box, but someone has commented recently that they were charged £5.50.

Prescription strength ferrous fumarate cannot be bought without a prescription from all pharmacists - Boots don't sell it, for example. I buy from Lloyds. Shop around if you have to.

I've also tried ferrous sulphate. I couldn't tolerate that at all. But I have read of some people with the exact opposite experience to me. So, as I said before, you have to experiment.

With each iron pill take 500mg - 1000mg of vitamin C. Iron is constipating, vitamin C may cause diarrhoea. If you get the quantities right you can keep things moving normally. Vitamin C also helps the body to absorb iron. As a bonus it is also good for the adrenal glands.

It is not a good idea to take iron for long periods without regular thorough testing because iron overload is very damaging and poisonous.

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Humanbean, my doctor has just prescribed ferrograd sulphate tablets 325mg in a controlled release Graddumet equiv. to 105mg elemental iron. Are these also bad?

I've actually bought my own iron from amazon;


I capsule is 20mg of elemental iron so I take 5 a day with dinner. You have to take Iron Bisglycinate with food, so I make sure I don't have any dairy, and have it with apple cider vinegar and 1000mg of vitamin C

I was thinking of going on ferrograd sulphate after my iron bisglycinate runs out, but I won't if they are rubbish, I'll just buy more bisglycinate from amazon


If they are slow release/controlled release, then the BNF says they shouldn't be used. (See the quote from the BNF I posted.)

I suspect that doctors prescribe iron like this because people tolerate them better than normal supplements, so the doctors probably think they are being kind. But ultimately the patient is not getting the iron boost that they really need, and the process of getting iron stores up is going to drag out far longer than it needs to.

If you have a hard time tolerating normal supplements then carry on with it. But it could be a long slow process to getting your levels up.

I have no experience of iron bisglycinate, so can't help you with that one, sorry.

Edit : I just noticed your post lower down. You seem to respond well to ferrograd, so you should probably stay on it. Why change a winning formula?


humanbean, regarding Ferrous fumarate 210mg, is 210x3 a day too much for the stomach to take? I currently take 100mg iron pills and they make my stomach a bit upset.

my iron level is 22, how long do you think I should take Ferrous fumarate 210mg x 3 a day?



I was taking Ferrograd tablets last year when my ferritin was 35. Is your partner suffering with hair loss too?

I think I was probably prescribed the same ones I've just been prescribed again this year (see above post).

Last year it took 3 months to get my ferritin to 103 on these tablets. I was told to take them on a empty stomach, which I did in the mornings. I could do that last year, as this was before I was on thyroid medication. You can't take iron at the same time as thyroid meds. You need a 4 hour gap.

However, I need my ferritin around 130, I've had another iron tests to make sure I'm not toxic at this level. We are all different. I read that some people can still be iron deficient if their ferritin is below 100. The reason I am not taking these tablets this year, is that Ferrograd constipates me (even when I take 1000mg of Vit C) so I bought Iron Bisglycinate. Although now I take 2000 Vit C a day and magnesium so maybe I wouldn't have that problem (??)

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Why not take the ferrograd, vitamin C and magnesium, and just see what happens with regard to the constipation since you react so well (in terms of your ferritin going up) to the ferrograd? Getting your levels up so quickly is amazing, and I have to admit to being a wee bit jealous! Mine took 18 months to go from 21 to just under 70. I've never come across someone who got their ferritin up so quickly with ferrograd before!


Really? Well that's encouraging for me. I'm gonna finish the bottle of Solgar first and then try. I can't take it in the morning because of my thyroid meds, so I could take it at bedtime (and make sure it's taken 2 hours after eating).



Take the iron with the vit c, but separate from Magnesium as they compete with each other


That is amazing to hear that you got your iron up to 108 in only 3 months.


On the solgar, this time round I got my ferritin up from 52 to 108 in 8 weeks approximately.


That also is amazing. Please would you tell me more....how many a day did you take, and when did you take them, ie before or with food, time of day. Were they better on your stomach? Did you take anything else as well, or do anything else to help it go up so quickly, food etc.....Thanks a lot.


I just saw your post about taking 5 a day, and taking it at dinner and with apple cider vinegar and 1000mg vit C. That's interesting because I read an article yesterday that explained how the iron salts are made and how they need acid to be re activated and so absorbed. So maybe that is the secret, apple cider vinegar, good for you.

Please would you let me know how much a c vinegar you took and if you took the tablets with it? Also, was it ascorbic acid that you took for vitamin C?

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I took a tablespoon of ACV mixed with water straight after I took my iron. I drank it through a straw so not to harm my teeth.

I would make sure my dinner was always diary free, as calcium can effect iron absorption.

Yes it was absorbic acid...I bought it from the supermarket, the ones you just chew. I took 1000mg, but now I take 500mg.

So basically ate my diary free dinner, then took 5 solgar gentle iron capsules, took the bit c in the middle of these 5 tablets, then drank my ACV.

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vit c not bit c!


Thank you, that is really good to know.

Did you find that form of iron gentler on digestion?


Yes no constipation with it.


Wow, that is great. I am going to try your method since it works so very well for you. Thank you for your replies. All the best.


A bit of vit c!

Technically ascorbic acid is not actually vitamin C.

It is a synthetic version of it. But obviously it is working very well for you.


Where can you buy real vit c? Or what is it called?

On the tub it says chewable vitamin c. Ingredient 500mg vitamin c. So is that vitamin c or a synthetic version? I'm not sure


Thank you.

Your magic formula for iron works.

But I have just found a wonderful iron product which is not a tablet. Instead it is a liquid iron angstrom sized (nano partical) which means that it doesn't need to be even digested, as goes straight into the blood stream, and is absorbed almost 100%. So hopefully, this is the end of needing to take high doses of iron....


I wonder how you are doing now on your new iron product. Just found out why my hair is falling out, ferritin at 54 but doctor said it was 'fine'. Could you send me the product name please, thanks x


Could you also send me the product name too aliveandwell.


hi alive - (: . very encouraging comment, product name? mind my asking how long you took it for - still?


Would love to know why you need your ferritin to be around 130, I think that is interesting, please would you say more, thank you very much.


For me, it's when my hair stops falling out.

Isabella Wentz, google her, says ferritin should be 90-110


Thanks for all the suggestions all - we got galfer today so he's going to try that instead....

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