Thyroid UK
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Confused about iron supplements

Hi guys.

Can anyone tell me what iron supplement to take, how, when and which one to order in what strength. I am so confused reading about the different types, everyone is suggesting different sorts! My Ferritin level is low but my doctor said its in range!

I take 100mg of Levo late at night. 2 hours away from food and 4 hours away from vitamin tablets.

What I'm taking at the moment:

Juice Plus multi vitamins:

Vitamin A - 490ugRE

Vitamin C - 155mg

Vitamin E - 22ug

Folic Acid - 376ug

Selenium 400mg (top daily dose)

I take these together in the morning with breakfast. Then again in the evening with food but not the Selenium. Levo late in the evening, 4 hours later.

My blood test results:

B12 - 1107 (15-150)

(Don't know why B12 is high I am not supplementing it, was having well woman multivitamins but have stopped 3 weeks ago)

Calcium 2.39 (2.22-2.6)

Vitamin D 92 (50-144)

Ferritin 25 (15-150)

Folate 12.5 (3.8-16)

Thyroid results:

TSH 3.54 (0.3-5.5)

FT4 25.3 (12-22)

FT3 3.7 (3.1-6.8)

It looks like I'm not converting so osteopath recommended I take top dose of selenium)

I want to up my ferritin levels, need to get something quickly as I know it will take time to raise its level. Currently off work sick, fatigued all the time, can't think straight, cold, aches, no motivation to do anything. I'm in limbo and getting very frustrated and depressed.

Can anyone please advise... At the end of my tether! Oh yes, no help from GP lol! Told me to eat well and go home and meditate! 😡

Thank you x

27 Replies

He told you to take selenium without testing your levels? Hmmm - not sure if that's wise. Everything I read says don't take any minerals or metals without testing first.

If you eat a small handful of Brazil nuts a day your body should absorb the selenium it needs, rather than forcing in a supplement.

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Ty. He didn't test. He said my thyroid isn't working properly and I'm suffering from exhausted adrenals and so told me to take selenium to help them both. And to help convert T4 to T3.


Well, no, not necessarily, MichelleBerko. It depends if the Brazil nuts have any selenium in them! Amounts vary, because soils are depleted. It's a very haphazard way of getting your selenium.

You can take up to 200 mcg without testing. It's not always useful to test minerals, anyway. Magnesium, for example, will always be somewhere in-range, because of the way the body handles magnesium. But it's OK to take about 350 mgs, because, again, soils are depleted, and most people are deficient in magnesium.



My Serum ferritin level is 13 and I am a walking zombie. I was prescribed ferrous .... something (fog brain again). I have switched to ferrous gluconate today, 3 times a day and hoping this helps.

Other have recommended Solgar Gentle Iron which I haven't tried but lots of people say its good.

Good luck


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The one that is current recognised as best and cheapest to raise levels is ferrous fumerate. It contains roughly 65-70mg of elemental iron per tablet. You have to get it from a pharmacy e.g. Boots, Asda, Tesco or online from Amazon, making sure it's from a pharmacy. If you go into a pharmacy to get it off prescription you will have to tell the pharmacist - "I have been told by my GP to get this as I have low iron" so make sure it's not a pharmacy you get your normal prescriptions from. This is because they have to confirm why you want them as they can be poison in the wrong hands. Get a pack of 84 which is about £3.80.

Take one two times per day with a vitamin C supplement and water. Ensure you take it 4 hours away from thyroid medication and two hours away from other food, drink and supplements to avoid interactions.

This is the link -

If you have problems with ferrous fumerate try taking only one per day before bed. If that doesn't work then try ferrous gluconate or ferrous bisglycinate. Both these are much more expensive than ferrous fumerate.

Ferrous gluconate you can find generics of it on Amazon and make sure it says that it is around 300mg as it contains about 35-38mg of elemental iron. A common brand for ferrous bisglycinate is Solgar gentle iron, which again you can find on Amazon. This contains about 20mg of elemental iron.

Once you have finished your course wait 7 days and have another blood test to see where your levels are.

Finally iron supplements like Floradix and from places like Holland and Barrett don't contain enough iron for someone who is deficient.

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Thank you for your help.

Ferrous Fumerate it is then. Got to start taking something!

So I need to take 1 tablet twice a day. Do I need to take a separate vitamin c tablet at 1000mg with each tablet or just one of them for example in the morning?

And I need to take it 4 hours after Levothyroxine and 2 hours after food, drink and other supplements.

At present I take vitamin a, c, e, folic acid and selenium with my breakfast. I take Levothyroxine late at night. So I can take the first iron tablet 2 hours after breakfast.

When can I take the second one because I take vitamin supplements at 6pm with food and then Levothyroxine around 10pm? Shall I take the second iron tablet at 4pm? 2 hours before my my second batch of vitamins a, c, & e?

Will that be ok?

Sorry for all the questions, I'm confused because I can't think clearly... Brain fog etc.

But thank you for your help.


Naz67 Yes, you need 1000mg Vit C with each iron tablet, it aids absorption and helps prevent constipation.

If I was taking what you are at those times, I would look to be taking the second iron tablet at around 4pm as you suggest.

By the way, folic acid isn't the best way of getting folate. It's synthetic and has to be converted into folate by your body and not everyone is good at that. Methylfolate is natural, doesn't need converting and the better form.


Thank you SeasideSusie. The folic acid comes with the Juice Plus vitamin capsules. I'm not taking folic acid separately.

Taking two vitamin c tablets at 1000mg each will equal my daily intake to 2000mg. Thing is I'm already getting 310mg vitamin c from the juice plus capsules. Is it dangerous to go over 2000mg of vitamin c in a day?


Naz67 You can take more Vit C than that. I take a total of 4000mg a day, some people take more on a daily basis. Vit C is water soluble so you pee out any excess. You can take Vit C to bowel tolerance if you want and we all have our own levels, 4000mg a day does not cause me any bowel problems, other people may find that is too much.

We all have to do our own research and make our own minds up but I'm very skeptical about Juice Plus, for a start it is Multi Level Marketing (pyramid selling) and it contains the wrong form of folate (folic acid). They seem to be very shy about saying what form the other vitamins take. A quick Google hints at Vit A being Beta-carotene which is the wrong form, we should take Vit A as Retinyl Palmitate (or Retinol), and it doesn't seem possible to find out what form of Vit E they use. Personally, I would look at testing and then supplementing any deficiencies I have.

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Yes I have read up about juice plus reviews. The osteopath made me order them lol so I may as well finish them off at £57 for 3 months! I totally understand what u r saying about the folic acid and the beta carotene etc... I was desperate and confused at the time was willing to take anything! Do u think he could b a seller?... In their pyramid lol!... Whatever it is I'm going to finish them off... Hope they give me some benefit!!

I will look into testing again and seeing what deficiencies I have.

Going to start iron today with 1000mg vitamin c with each tablet.

Can I get supermarket vitamin c from eg Tesco's? Will it be good enough?...


Naz67 I've just had a quick google and the Tesco ones seem to be either chewable or effervescent. They do seem to contain stuff we don't need and I like to stick to as little unnecessary ingredients as possible.

If you are OK with ascorbic acid (which the Tesco ones would be) I would just stick to ascorbic acid powder and make a drink with some OJ perhaps.

This is the one I use

It is the L-ascorbic acid type which is supposed to be better than the D-ascorbic acid type. When I bought mine it worked out at less than 4p per 1000mg and you'd get 454 x 1000mg servings out of that pack. I just dissolve it in some OJ and sip through a straw to help prevent any damage to tooth enamel.

I try to use as few tablets/capsules as possible.

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Hi seasidesusie, how much vitamin c do I need in a glass of orange juice? I assume 1gram but how do I measure1 gram lol?... I think a teaspoon is 5 grams lol!

Any ideas? What do u do?

I ordered the one from Amazon lol!


Naz67 I know that one teaspoon is 5ml and I've just weighed one level teaspoon of Vit C powder using my kitchen measuring spoons, it weighed 6 grams. I have some digital kitchen scales that measure in 1gram increments so that's how I do mine.

1 gram doesn't look very much at all. I add about 40ml or so of OJ and drink through a straw to protect tooth enamel.


Ty seaside sue... I will have to estimate then lol! Can't go too wrong. My electric scales are broke!! Ty Hun need to start taking today as I've waited too long. X

Can't think straight!


Seasidesusie I have started my iron tablets at last today lol. Thanks to u! I've put 1/6th of a level teaspoon in orange juice... No belly ache and I hope no constipation! Whoo hoo!

Thank you for being so helpful... Couldn't have done it without u!


Naz67 I hope you get on OK with the Ferrous Fumarate, it would be no good for me, even 5mg iron bungs me up! If you do get constipated then Dr Myhill recommends 2000mg Vit C before bed to produce a bowel movement next morning.

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Ooh let's c if I get bumped up lol... Been a while since I've had iron tabs lol! Ty


Hi SeasideSusie

I just wanted to thank you again for your advice on iron tablets and vitamin c...

All is going well, I'm taking ferrous Fumerate twice a day with a gram of vitamin c dissolved in oj... No adverse effects so all good!

Any advice on a b complex?... I've got high b12 when I'm not even supplementing... Any ideas please? X


Oh, well done Naz67 :)

Normally Thorne Basic B or Jarrows B Right are the ones recommended. I've checked both of them and would suggest you look at the Jarrows as that contains only 100mcg B12 methylcobalamin whereas the Thorne contains 400mcg. Seeing as your B12 is already high you don't really need the extra amount in the Thorne brand.

Be aware that your urine may be bright yellow when taking a B Complex, it's normal, it's the B2 Riboflavin.

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Thank you SeasideSusie . Now onto the next mission... A B12 complex!

Hey more good news, managed to get T3 out of my endo! Gonna start that tomorrow. Are u on T3... Any advice please? x


Naz67 I self medicate with T3, GP not involved, I try to keep away from her!

Well done on getting it from your endo.

Not sure what your endo has advised about the T3 for you but it's usual for self medicators to start low and wait to see what happens, then build up slow and gradual. I started with 1/4 of a 25mcg tablet and lowered my levo by 25mcg. I started with 1/4 tablet in the morning. When I increased I added a second quarter in the afternoon. I am now on 3/4 tablet and take half a tablet in the morning with my Levo (early hours when I need the loo then go back to bed) and 1/4 tablet in the afternoon.


SeasideSusie , forgot to ask... Can I take the b complex with food? Or when?.... I'm popping pills all day and night lol... 4 hours after this... 2 hours b4 that... Can't cope lol!

Not enough hours in the day!! 😜


Naz67 The Jarrows B Right says to take with a meal. It's recommended that any B vits are taken in the morning, no later than lunchtime, as they can be stimulating and you don't want your sleep affected. I take mine with breakfast as that's a few hours after my thyroid meds, like other supplements two hours away is the norm (except for iron, mag and Vit D as you probably know which should be 4 hours).


Bluebug what ferritin level were u at when the doctor gave u iron tablets? Thing is, I am in range but scraping the bottom of the lowest end.

How long shall I take the tablets for? A week or a month or check levels after 4 weeks and go from there?... I'm worried about getting too much. GP said my level was in range so will have to think up an excuse to get my blood tested again lol! I can't afford to pay privately.


This all may be a lot of information but take your time reading it and understanding it. I didn't learn about iron and the importance of it in one go, and there is still more stuff to go through.

For starters did you read the link I put in my post? It would be worth reading that as a starting point. Doctors and nurses, who are doing their jobs properly, also have to look things up and ask colleagues/specialists for advice.

If you take 2 ferrous fumerate per day it will take you about 3 months to finish the course. However with the bowel issues some people suffer it may take you 4 months. (This is why I don't recommend taking 3 per day.) If you find after 2-4 weeks you have to swap to ferrous gluconate or ferrous bisglycinate it may take you 6 months to finish the course.

After that wait 7 days and get a blood test to see what your ferritin level is. You don't need a blood test before this as ferritin levels actually rise slowly.

Humanbean has explained why you need to be tested and that you want to be mid-range. One of the reasons for this is that ferritin levels can rise in inflammation and infections. So to confirm that your level has risen just due to supplementation you also need to ensure you have a test that confirms this. Blue Horizon do various pin-prick tests that including testing ferritin and a C Reactive Protein, an inflammation marker, levels.

In regards to convincing your GP to treat you - under NICE guidelines GPs don't have to treat you when you are in range it is left to their clinical decision to treat you and when to treat you. In your case your GP has decided not to. This GP is like many GPs who think they are saving money by doing so.

In my own case, I with the first GP practice I've been with in my life who will treat low but in range ferritin levels. In fact this is the first GP practice I've been with where some of the GPs even know what ferritin is and why it is of importance. Every single other GP practice I've had since a teenager I've had to fight to get iron tests from. Unfortunately I changed to this practice after I learnt how to self-treat various issues so I sort myself out as it saves time and is much less hassle.


I used ferrous fumarate 210mg, one tablet, three times a day. I took that dose because it was what my doctor prescribed when I first started supplementing iron. She stopped prescribing after two months, so I continued buying my own without prescription. I bought it in packets of 84 tablets (from Lloyds or Tesco pharmacies), which is enough for 28 days when taking three per day. There is 69mg of elemental iron in a single pill of ferrous fumarate 210mg. Taking three per day I was taking 207mg elemental iron in total. I would consider that to be the highest safe dose.

I had terrible problems getting my iron and ferritin levels up. I really didn't absorb very well at all. I supplemented for nearly two years to get my ferritin up to just over mid-range. In the end I only managed it after I went gluten-free. I am still supplementing one tablet of FF three or four times a week. When I stopped supplementing altogether for four months my ferritin dropped enormously.

I am not medically trained, by the way, so always do your own research. Anyone supplementing iron should get tested regularly because excess iron is poisonous. Ideally, levels shouldn't go higher than mid-range.

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I am gluten and dairy free at the moment. Going to try ferrous Fumerate twice a day and get tested in a few weeks.

Thank you for your help. There's so much good info on here. I wish I could think a little clearer to move a little faster!

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