Do B12 injections deplete iron/folate... - Pernicious Anaemi...

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Do B12 injections deplete iron/folate &/or other B vitamins?


Hi all, my B12 was virtually non existent in July but since loading injections followed by monthly injections my brain fog, dizziness, memory & confusion have all improved. However my physical fatigue & headaches have got much worse. I have a lot of problems with reactions to supplements & have struggled for years to improve my iron levels. Prior to B12 injections my ferritin had risen from 5 to 22 ug/L but since injections has gone back down to 9. My folate has also dropped from 8.95 to 6.95 ug/L & a methyl cycle urine test shows that all my B vitamins are also low. I'm working on improving the levels but until then I'm worried that having more b12 injections may be depleting my other vits.

Can anyone tell me if the B12 injections are likely to be depleting my iron/folate or B vits please?

10 Replies
clivealiveForum Support

Bev11 You are "proof positive" that it is not uncommon for some symptoms to appear to get worse once B12 treatment has started and it gets to work repairing the damage done to your nervous system.

I'm not a medically trained person but I do know that Folate gets "used up" processing the B12 so it is essential to have a healthy level andI guess the same would apply to the other Bs.

I hope you soon start to see a lessening of your symptoms

Bev11 in reply to clivealive

Thanks Clivealive


It isn't the B12 injection that is depleting your vitamins but vitamins do tend to work together so if you body now has enough B12 for various processes and healing it is likely to use up more of the other vitamins that are used in those processes. Folate is a particular case in point.

Ferritin is a protein that binds to iron so the body can use it, so it can be an indicator of iron deficiency. I'm not aware of any direct chemical processes that would use both B12 and iron. If you had macrocytosis when you were diagnosed then your body will be replacing old deformed red blood cells with healthy new ones - and the new healthy blood cells will have a lower iron content as a result.

Suggest that you speak to your GP about the ferritin - the result needs to be evaluated in relation to other measures of iron

Bev11 in reply to Gambit62

Thanks Gambit62, that makes sense. I'll speak to my GP but he's pretty useless with anything B12 related, people on here are much more helpful & knowledgeable so I thought I'd ask advice on here first. Thanks.

Gambit62Administrator in reply to Bev11

ferritin isn't B12 related - iron related. Iron based anaemia tends to be a bit more straightforward than B12 deficiency so may be more familiar.

vitamins likely to be a totally different matter.

Bev11 in reply to Gambit62

Ok thanks

My understanding is pretty basic but it is this: The three components that the body needs in order to create red blood cells are iron, B12, and folate. When you're low on any of the three, your body can't use just the remaining components to go on making cells, so those components continue to exist in the body but not get used. (This lack of production causes anemia.) When you get more of the missing component, the body begins making more cells. Since it is making the cells from all three components, all three are being pulled from. So it does make sense that, if you were low enough in B12 to have become anemic, and you've now been given B12, your body is trying to catch up on cell production and is drawing on the folate and iron in your body for that purpose.

Personally, I have found that I always need to supplement with folate on the day of my injection. Everyone seems to need to find their own individual balance of what additional supplements their body needs. It sounds like you're on the right path since you know to watch your levels of other nutrients.

Thanks for that Galixie, that makes sense. I'll work on supplementing & keep monitoring my levels. Thanks

Interesting question and I wish I knew the answer. Like you, many of my symptoms have improved with B12 injections, but the tiredness/falling asleep has got steadily worse and the headaches have not improved (which was my great hope). I noticed some improvement in both with a few weeks of Spatone iron recently, and thought this was the answer, but then things reverted to how they were, in fact the migraines worsened.

Following the thread with interest.

This is a great resource:

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