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Ferritin, TSH, gluten and B12 blood test results advice please

Has anyone had success increasing their iron levels?

I've been trying for about a year now without success. The levels have moved from "15" to "42" even after supplementing with 400 mg (I think it's mg and not mcg) of iron supplements prescribed by my surgery (200 split into two doses).

I take 75 mcg levo and 10 mcg T3 (liothyronine) - T4 in the morning and T3 at midday without food.

I'm also taking daily supplements of Vitamin D 1000 IU (25 mg), Vitamin C (500 mg), Zinc Orotate 9.54 mg that is packaged with 18 mg Magnesium (as magnesium carbonate and magnesium stearate), and Selenium 200 mcg.

Note: my TSH has dropped by almost 2.5 points since I've been taking the T3 (about 2 months now). I have not adjusted the T4, as the doctor wished me to go from 75 mcg to 50 mcg, but perhaps I now should? I have been feeling strangely: dizzy, moody, very thirsty, low energy, strange clarity and very worrying eyesight issues - I have a blind spot now in my right eye as my optic nerve has somehow been damaged (it is 'dipping' and not circular as before) and doctors have no clue what's causing it.

The doctor requested T3 testing but the lab did not do it.

I'm considering trying Nature-Thryoid if I can source it from a reputable manufacturer.

My test results were:

For gluten sensitivity - Tissu transglutaminase IgA lev: 2.6 U/ml (range 0.0 - 10.0)

Serum vitamin B12 - 209 ng/L (range 130-900)

Serum folate - 6.4 ug/L (range > 3.0)

Serum ferritin - 42 ug/L (range 15-300)

Serum TSH level - 0.25 mU/L (range 0.30 - 4.40) "Low"

Serum free T4 level - 13.3 pmol/L (range 9.0 - 19.1)

I've heard that supplementing with Folic Acid (although I'm not sure at what dose) can help with low folate levels - is this true? Also, I'm not quite sure what the folate top range is.

Thank you!

6 Replies

It's not just your folate you need to raise. It's also your B12 which is dangerously low.

Optimal for b12 is 1000, but anything under 500 can cause irreparable neurological damage - your eye, perhaps?

If I were you, I would supplement with 5000 mcg methylcobalamin daily. With that, you need to take a B complex to keep the Bs balanced. If you get one with methylfolate, that will raise your folate. Don't take folic acid, it is not well absorbed.

Your ferritin is also too low. It needs to be more like 100. So, supplementing that with ferrous fumarate would be a good idea. Take 1000 mg vit C with it, to aid absorption.

Your TSH is not low, it is irrelevant. Once you are taking any form of T3, your TSH and FT4 will be low, the most important number - the number to dose by - is the FT3. Without it, you have no idea where you are. The doctor should mark on the form that you are taking T3, see if that helps get it done.


Serum vitamin B12 - 209 ng/L (range 130-900)

Serum folate - 6.4 ug/L (range > 3.0)

Serum ferritin - 42 ug/L (range 15-300)

All much too low still. You need methylfolate (usually as part of a B comples - eg Thornes) not folic acid - aim for about 10 or 11, but higher isn't a problem if B12 is good - and methylcobalamin for B12 (eg Jarrow formulas 5000iu a day) until your levels are over range. You say your ferritin is increasing, but it would still help to supplement until ferritin is at least 70. My eye problems (esp double vision and tics) are much worse when my B12 drops below 1000, but I don't know anything about blind spots except as a side effect of migraine. The type of magnesium in your supplment isn't going to do anything good at all. You need magnesium malate, citrate or threonate. Oxide is basically the least available type (the magnesium version of a stick of chalk) and stearate is a (possibly harmful) filler to make the capsule or tablets easier to make.

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The book - could it Be B12 ? - by Sally Pacholok is a must read for everyone. I have just bought the 2nd Edition and have discovered so many new things.


Can you specify exactly what iron supplements you are on, please. The name of the product and the dose.


Have you had your vitamin D level checked? When supplementing we need to check levels twice a year.

Also you need to add some vitamin K2 mk7 when taking vitamin D, to help the extra calcium that circulates, go correctly into the bones.

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folate is the form of B9 found in food. Folic acid is an artificial form of folate. You can also get methylated forms of B9 which some people find work better for them but it is much more expensive and the problems with processing B9 (generally MTHFR - caused by specific genetic variants) only mean that you are less efficent at processing folic acid not that you don't process it at all.

At 209 your levels of B12 are in the statistically normal range. this means that the majority of people have no problems at this level. However, individual responses to B12 are such that some people will have severe problems at this level. What really counts with B12 deficiency is the symptoms and you can find a checklist of symptoms here


as you will see there is a considerable overlap with thyroid which can make diagnosis very difficult as GPs aren't necessarily aware of it.

There is a lot of hype around methylcobalamin. It is true that people with MTHFR genetic mutations are less efficient at processing un-methylated forms of B12 such as cyano and hydroxo but again this is just about being less efficient and not about being unable to use these forms at all. There are some cases of people who are not able to convert methyl to adenosylcobalamin (but they will be able to convert hydroxo to both forms) and the body needs both forms ... methylcobalamin does not work for everyone.

Ideally you should get a B12 absorption problem properly diagnosed before you start treating yourself. The B12 serum test is not the most accurate - symptoms need to be taken into consideration - two tests for waste products that build up when the body doesn't have enough B12 to process them back into useful building blocks - MMA and homocysteine - tests can be difficult to get done. GPs are often unaware of the problems in interpretting B12 serum and that symptoms really do need to be evaluated and generally have a poor understanding of how a B12 deficiency works - they will be focused on looking for macrocytosis - though being low in ferritin may counter this as it may be indicative of an iron based deficiency which will result in red blood cells being smaller.

If you need help trying to get a B12 absorption problem identified then I would suggest that you join the PAS forum and post there.


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