Ferritin test results skewed, b12 not resolved or something else?

First time here... first time posting about my health online. I'll try to keep this short. 5 months ago I started experiencing numbness in foot and tingling in hands and feet. Blood test showed B12 was 221 - within the normal range but I started taking the sublingual methyl-b12, 5000mcg daily. I also started taking iron with vit C because my ferritin was 23. No anemia. The tingling stopped in a couple of weeks but turned into weird vibrating, then burning feeling in my feet. Always in the afternoon when sitting at work, usually lessening at night and not interfering with sleep. I also had my toes or entire arm fall asleep during the night and take a lomg time to come back to life.

Since then, it got better and I lowered the b12 dose, then raised it again when the symptoms persisted. Tried adding folate and other B vitamins. 6 weeks ago I stopped iron as was getting constipated. Started a gluten free diet, which made me horribly bloated at first (not the unhealthy gluten free, more just wheat free with more veggies, smoothies, liver) Became almost symptom free but then had a couple of tummy bugs and digestive issues and the foot burning came back. My fingers and toes started falling asleep again when sleeping, but would recover quickly. A couple of weeks ago I started taking iron again and it gave me a lot more energy and seemed to improve circulation... but then I had another blood test. I had taken 2 iron tablets within the 24h before the test and my ferritin was over 70. Folate was high. I asked the doctor and he said the tablets wouldn't have significantly affected the results. So I stopped taking iron and feeling more tired, toes permanently cold and the foot burning slightly worse. I was also tested for h pylori (neg) and other bacteria/parasites (neg). TSH 1.48 (was 2.01 before), no diabetes.

So, can this still be b12 related (if it ever was) or what could it be?

There have been other minor sensations / symptoms but pretty fleeting and I'm a sensitive person so I wouldn't say they are significant.

I'm 36 and mother of one. Had thyroiditis after pregnancy (hyper, then hypo) but it settled. Healthy diet, no alcohol, no smoking... but clearly becoming a hypochondriac :)

20 Replies

  • Hi Enni you don't say whether your serum B12 was measured in with the other tests you had done a couple of weeks ago.

  • yes it was measured - 1100. I suspected that's reading the supplements so it wouldn't tell my real level. I am thinking of stopping b12 for a few weeks to test the real level...

  • Ferrous bisglycinate or fumerate are less likely to cause constipation. 70 is not too high, and you may find your ferritin level drops again. You could continue with a low dose supp, say 100 per cent RDA.

    Have you excluded celiac? You should do that before going on a gluten free diet. You might not be celiac, but you are best to rule it out first. A g free diet is not dangerous, by the way, but Just cutting down on wheat a bit is pointless, it will achieve nothing if you really are g sensitive. The bloating would not have been caused by cutting it down. Maybe the extra veg did that, or your gut is worsening.

    A TSH result is not very helpful. If you can afford it, do a private blood test, a full panel including antibodies. Did tests after pregnancy include antibodies? Do you know if you have them?

  • thanks. No, haven't had a celiac test. I was told gluten can mess with iron absorbtion so that's why. I did mean I went gluten free, not just wheat free - sorry about the confusion :) Just meant that I'm avoiding the GF products and having more sweet potato etc. Not totally grain free though.

    They measured antibodies after pregnancy, that was negative.

    Ferrous fumarate is what I was taking before the test and it hasn't been that bad for my stomach (was on another brand earlier)

    I'd also been taking spirulina powder for a week (including that morning) Could that affect the test results?

  • Antibody negative ... Do you have the results? Was it close? Might they have crept over in the meantime?

    You can get an on line test for celiac if the gp refuses ... you do need to be eating gluten for several weeks before it though.

    Hmmm .. the numbness and tingling do sound like autoimmune atrophic gastritis, which can eventually lead to outright PA, don't they ...

  • That was over 3 years ago so could be different now. But since h pylori came back negative I'm hoping the gut issues were just viral infections etc. My husband caught the same bug, we both got better but then I had another round a week later and lingering symptoms for another week. It's better now, only random tummy aches on some nights.

  • Hi Enni, you could have wrote that for me, I've been exactly the same as you, my B12 was 233, also Hashimoto's thyroiditis, this B12d came about 2 years ago, now having gut problems, I saw a Neuro who got me ijnjections in September numbness & tingling gone, but returns near injection time, my moods were terrible too, very teary,

    I would say you need B12 injections, I'm still learning about all this too, hope you get sorted :-)

  • Great to hear you've found something that works! It's really hard to get injections in New Zealand since my levels were not under 140. I've found that magnesium helps with anxiety and mood swings (and other PMS symptoms!) but I can only tolerate 200mg per day. I hate swallowing those horse pills so I just drop one in my water bottle :)

  • Hope you get sorted over there, it's very hard where ever you live I think, good idea putting mag in the water bottle never thought of that, perhaps look for a new neurologist over there that can help you, I've found a nutritional person that's going to help with symptoms, hope you get you much needed help soon x

  • I don't believe there are that many hypochondriacs. Alpha lipoic acid is supposed to help nerves. Sorry I don't know what's causing your troubles

  • Thanks for mentioning Alpha Lipoic acid. Just looked it up and am going to try it.

  • Thanks. I actually got some and tried for a little while but didn't notice much. I read somewhere that it's been proven helpful for diabetes related neuropathy.

  • Being a good little skeptic I looked this up - and there does seem to be something in it. Studies so far on oral dosing have been too small, but IV alpha-lipoic acid certainly seems to help with neuropathic pain due to diabetes. search.proquest.com/openvie...

    I don't think they actually fix the nerve damage, but a bit of extra pain relief might help.

  • Hi! A little update... I wanted to test if B12 has anything to do with my symptoms so went on a lower dose for a few days, then took over 10,000mcg on one day. Lower dose only made my toes feel a bit numb. the high dose immediately fixed that but made my skin burn that night - the burning feeling traveled from one spot to the next all around my body and I was too awake to go to sleep until 2am. The next day I didn't take anything and felt fine, apart from a little of the same skin burning at night. And this morning I woke up the tips of my toes fallen asleep.

    Does this mean I couldn't even handle the shots? Can higher dose really affect someone that much or it some kind of weird coincidence?

    Any thoughts appreciated!

  • I think the burning is one of the signs of nerve healing. After I started injecting the numnbness turned into a pretty bad burning feeling and lasted about a week. The burning then turned into pins and needles, then slight tingling, and now it's alternating between tingling and what I've read here referred to as "socks and gloves" feeling.

  • that's good to hear. I haven't had injections but when I first started taking b12 supplements the numbness and tingling did turn into a burning feeling in my feet, which sort of comes and goes. It's been a couple of months though so I'm not sure when it's going to go away... the burning skin in other parts of the body is new, I haven't experienced any numbness or tingling on my back, shoulders etc. so is it even possible I have nerve damage in these areas?

  • I'm not sure, but I suppose so. On some days I have tingling in areas that never felt numb before (e.g. upper arms or thighs, parts of back, etc).

    You might look into injecting rather than supplements. If you have an absorption problem (e.g. PA) then you won't be able to absorb much of the B12 so you might be slowing your recovery. Plus injections are probably cheaper if you're having to take such high doses.

  • I had taken 2 iron tablets within the 24h before the test and my ferritin was over 70. Folate was high. I asked the doctor and he said the tablets wouldn't have significantly affected the results.

    Your doctor might need a bit of a refresher on how iron tests should be conducted.

    Read the instructions on iron blood tests on this page from the NHS Choices website :


    And if you want to know how much iron you are hanging on to without interference from pills, the STTM website suggests you leave off iron pills for 5 days before testing on this page :


  • Thanks everyone for your responses! I have an appointment this Friday with a female dr who I'm not quite so scared of - and who last time saw me for 15min instead of 5min, felt like such a luxury! She actually suggested I'd take B12 even if my results come back within range (which they did, at 221). I'm hoping she agrees to trying the shots since I'm still having neuro symptoms nearly 6 months later...

    My foot burning has changed to more of a 'stocking/tight skin' feeling, but it's now occasionally on my hands as well, sometimes on my face. Not sure if this means getting better or worse..??

    I've reading about the MMA and other possible tests but not sure which ones are available in New Zealand OR what the treatment guidelines here are. It seems most google results are about b12 shots for cattle(!) This country cares about its sheep more than its people :)

  • A little update: Dr told me there is no other test they can do to see if I'm absorbing B12 - well, not in this country - so she said I should just go off supplements for 3-4 weeks and see if my blood levels fall. If there's enough of a change (not sure how much that would be...) it indicates an absorbsion prob and I can get injections. I'm kinda scared I'll become a total vegetable but if it helps to get a diagnosis I'll endure... I ran out of the stronger supplements a week ago and have been taking less. The nerve symptoms are still minor but the brain fog is back and making it hard to get through the work day. ahhhhrgh.

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