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Could Multi vitamins containing folic acid be the cause of increased neurological problems?

Hi I've had fatigue for a long time now and recently found out that I had low serum b12 back in 2012 that wasn't treat. (I also had a low serum level in October this year and no b12 tests between these dates)

In May I purchased a multi vitamin spray that only had 6ug of b12 in it but 400ug of folic acid.

I used it until the end of June when I felt odd and more tired so I took a break then used it a few times in July then stopped it.

At the end of July I was incredibly fatigued and experience my first ever ocular migraine then I get an aversion to bright light and eventually to noise too. In August after a long brisk walk I take to bed for two weeks and my heart races every time I stand up. Some time after this I notice a burning sensation on my right thigh that's still here now but it's more like a strange numbness with occasional pulsing little shocks.

Is it possible the folic acid in the spray converted too much of my remaining b12 and resulted in how I was feeling?

I've now been advised that folic acid is bad before b12 levels are raised but didn't know any of this before joining here.

I'm tying to get a grasp of what went wrong?

I'm still trying to get b12 from the Gp (since October when I get a serum b12 done privately that comes back at 156pg but the gp follow up test is 314pg.

Yesterday he referred me to a doctor in the local hospital and said it'll likely take 6 weeks.

I'm currently using sublingual methyl b12 and not taking any b9/folic acid because I don't know what my true b12 levels are. (When I began I was using the multivitamin spray with the folic acid in but stopped it after advice on here about the folic acid before b12 injections) My mood and light glare have improved nicely but I still have the numb/burning thigh and now tingling legs.

I'm still very fatigued and the tinnitus I've had for years is ever present. I also lost 2 1/2 stone since July but that's mainly from before I started the b12 as I lost my appetite and had terrible feelings like anxiety. Since using the b12 spray my appetite has returned and my anxiety level is back to normal (in fact I'd say it's improved beyond normal). The fatigue is the biggest issue.

My private test in October showed low serum b12 but normal active b12. (Long shot but could the folic acid lower the serum but raise the active if you were chronically low in b12?)

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Hi Steap I'm not medically qualified but the most logical thing would be to have your serum Folate tested and go on from there.

What level of folic acid was in the supplement you were taking?


clivealive 400ug (in four sprays)

I took it for about 5 weeks from 29/5/16 I get light aversion at the end of July then it all goes pear shaped after August the 6th (that's the day my world changed after I take a long fast walk and get my heart rate up despite hardly exercising for ages)

My folate test in October was 5.57ug/l

The b12 serum was 153pg/ml but active was 67.8pmol/l


Would you require a high serum folate for nerve damage to occur?

The way I read it was that adding folic acid if you are serum deficient in b12 causes an unwanted increase in conversion to methyl b12 leaving the nerves open to more damage due to less fatty acid metabolism, leading to the break down of nerve coatings that don't renew quick enough.

I'm struggling though to understand how all this works and the fatigue makes taking things in even harder.


What were the ranges <from - to> of the B12 and Folate?

Your Folate "looked low" at 5.5 in October despite you supplementing with 400ug of folic acid in May but different labs use different ranges and anyway that is not an huge amount for just a couple of months. I've taken a tablet of that strength every day for more years than I can remember, but then I'm on B12 injections every three weeks

Folate is "used up" processing the B12 so if you start supplementing with B12 again maybe you should think about bumping up your Folate too if it is low.


B12 was 156 pg/ml 191-663

Active b12 was 67.8 pmol/L 25.1-165

Folate (serum) was 5.57 ug/L 4.6-18.7

I think you've seen these before Clive but here's the actual report


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Your Folate looks to be bumping along the bottom of the range the lab used and if (as you thought) you were "overdosing" in May/June it would surely be much higher.

Maybe it's a case that it is getting "used up" and you need your doctor to prescribe a supplement.

I wish you well and hope you find some answers

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I'm not taking any folate whatsoever now after advice on here not to use it until I start injections (if I ever get them)

I have been taking at least 2000ug of methyl b12 spray for ten weeks now. I was feeling better than I am now on the multi vit including the folic acid alongside the b12 but didn't want to worsen my neurological symptoms if the b12 wasn't being absorbed.

I think it is to some extent because since I've been taking it my legs tingle and get sore but it eases if I get a lot of extra potassium.

I'm also feeling much better psychologically and my visual symptoms are much improved too.

Surely that means I'm getting at least some.

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I wouldn't wait for the injections. You are getting some B12 via the sprays, your Folate level in October was low so keep taking the 400ug of folic acid whilst you are spraying.

As Gambit62 says they are "...not sure that the amount of folic acid you were taking would cause the problems you mention much more likely that it is just the deficiency really starting to bite..."


Like Clive I'm not a medic but I'm not sure that the amount of folic acid you were taking would cause the problems you mention.

much more likely that it is just the deficiency really starting to bite - symptoms tend to snowball - personal theory is that it is the point at which your reserves in your liver have all leaked away.

Also possible that there is something else going on. Do you know how your thyroid is? and there could be other things. Know that Hughes syndrome can cause migraines and a load of other things - sticky blood - but only from hanging around the National Migraine Centre forum.


They've never mentioned my thyroid but dare I say as far as I know it's ok.

Both my mother and sister have thyroid disease though.

Mum underactive on thyroxine and sister over (originally but now on thyroxine after treatment to destroy her thyroid)

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I suspect hardly anyone recognises early stages of low thyroid hormone levels in themselves for what they are. I only did because someone near me pointed out what was happening, so I asked my GP for a test, actually a series of tests over many months. Without that, everything could simply have been put down to getting a bit older, etc.


Hi Helvella, Does low thyroid also cause B12/folate issues? I ask re your post above. I am new to all this but am looking at B12 because of nerve damage symptoms - Burning mouth which has started since Christmas includes burning lips tongue cheeks gums. I have tingling in toes but burning in hands and fingers and noise in ears. I have started in panic taking Premier Research Labs B liquid complex - contains lots of B12 and natural folate as folinic acid. In October fasting blood tests showed TSH had risen to 3 (No drugs) Was 2.5 six months before. In April last year my serum B12 after supplementation was 550 but in Oct had fallen to 400 after no supplements. With folate mid range at 10+

My B12 had been low yrs before (191 rising 200+ 300+ as I started supplements)

I am confused about the relationship between B12 and folate. And whether I should change to taking B12 on its own? Did Steep not infer in her post that folate can cause the nerve sheaths to be damaged if Active B12 is low? It is really difficult to know what to do.

Can you help advise?

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I'm interested too! :)

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It seems likely to me that people with low thyroid hormone and/or autoimmune thryoid disease are more likely than most to suffer B12 deficiency.

Low thyroid hormone can result in low stomach acidity which results in less B12 being made available. Simply, making acid is a high energy process and requires adequate thyroid hormone.

Autoimmune thyroid disease is associated with autoimmune gastritis which can result in lower production of both acid and intrinsic factor. In some people, this gastritis might resolve.

I feel very ignorant of folate issues so would rather not answer than mislead anyone.


Can you tell me what role intrinsic factor plays? I have autoimmune condition (RA) but not as I am aware, digestive issues. And just incase I do have low stomach acid, I have lemon juice or cider vinegar or both with main meals


There are many here who know a lot more than I do.

It is a protein that attaches to B12 and carries the B12 safely through from the stomach into the intestine - where it should release the B12.

No Intrinsic Factor means, pretty much, no B12.

Autoimmune gatritis is particularly common in association with autoimmune thyroid.


High dose ubiqinol, magnesium and b12 drastically improved my fatigue. My haemotologist supported me doing this alternative programme. I went from sleeping nearly all day to now being awake all day!!. To heal my nerve damage my functional Dr also has me on ionic minerals, carnitine and omega 3 algae oil. Healing the digestive system is also a priority. I'm not a Dr but just wanted to say functional medicine has been the only thing to help me. I still have a long way to go but my feet burn less. Hands have improved but still have limited use. My Dr thinks that in time it's possible to heal them and get my chronic viral infections under control. I hope so!!

Ps sorry I wasn't sure about your folate question.


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