Absorption and Retention of B12

[Soulquest]

I understand that everyone is different in terms of how they absorb and retain different forms of B12, and I know it takes trial and error. That said, my understanding has been that B12 stores build in your liver as a result of getting B12 injections. But I don't understand how an injection can 'wear off' so quickly. I have had five weekly injections (cyano) since being diagnosed (switching to daily tomorrow), but I have not noticed any improvement. 48 hours after my injection I get half a day of feeling mostly normal which is refreshing, but then by evening I feel terrible again. Is it possible it takes my body two days to absorb it but that I don't retain it? How can you tell the difference between the injection 'wearing off', and symptoms of your nervous system healing and getting worse temporarily as a result? How do you know if your worsening or stubborn neurological symptoms are a result of not frequent enough injections vs giving injections enough time to build up and temporarily feeling worse because of it?

Before my diagnosis I had increased my sublingual (methyl) to 5000 per day, and by month two I was feeling a lot better. Is it possible for sublingual to be more effective than injection, or is it an issue of methyl being absorbed better than cyano?

Also, at what point in the treatment process do you declare that neurological symptoms are irreversible?

[Nackapan]

Hopefully never!I'm still making improvements 3 years in.

Noone knows

I was told most healing happens in the first yesr by a neurologist.

But no 'quick fix

He also said to keep up frequent b12 injections.

You are doing well to actually have times of feeling your 'old self'

I woujd say that's promising.

I've no answrs to many of your questions

It all seens to be theories as not enough research.

Also individual times of deficiency causing different symptoms.

Does sound like you may benefit ftom more frequent injections to try and stop the seesaw effect.

I personally would increase slowly and make a symptom diary.

It can take months to see if a regime is helping .

If we cant utilises b12 from food it's a absorbtion problem. So even if we have b12 in our liver stores we can't utilises it as the same process needed.

That's how I understand it.

Also make sure folate iron ferritin vit d at good levels. Other vitamins and minerals.

Perhaps take a multivit

Others can explain the process!!

I hope you improve soon.

[SigNi]

I am on the same path. Only this encouraging thought to offer at the moment - someone on the forum just told me she is still seeing neuro improvements 5 years later. That gives me hope for those things that don’t immediately right themselves. In the interim I am learning to do my own injections & have ordered my own supplies so I can tailor my dosage as needed. I started out with a worsening of my symptoms, but as of today am having a few good hours. I finally allowed myself some pain relief though & I’m sure that’s part of it. My injections are 2 x week at the moment. At 4 weeks the doc will reassess. Will go into internal medicine at a local hospital in about a month to try and find the root of my absorption problems. I also have a lot of other deficiencies & have supplements from one of docs that I will begin soon. You may have deficiencies aside from the B12 that are affecting you. Mine are B6, B1, Folate, D3, Omega 3, and Manganese (somewhat rare). Testing also showed a possibility of leaky gut. I presume until I address all of these I will continue to struggle. Sigh. Wishing you luck & comfort.

[Sammyo23]

Different kinds of b12 work differently for other people.

If you're getting results with b12 sublingual then you should keep taking that. Maybe twice a day? 3 times a day? There's relatively cheap bottles out there with massive amounts of pills you could experiment with.

You feel you're not getting enough, so no reason not to.

You can also try eating liver/liver pills, if you can absorb b12 through your digestive system. Lamb liver is has a load of b12 in it.

And you could try buying hydro b12 pills to see if those do anything for you.

As far as irreversible damage goes, I read that as long as the nerves haven't been killed off entirely, healing is still possible, if just very slow.

It would fit with how we've got people here who have been getting results after years of regular b12 doses when logically all healing should have stopped.

[Jillymo]

I am very much the same as yourself and still struggling with the awful symptoms despite being on treatment for a year now -

I started with a loading dose then the 3monthly injections wich did not sustain me so I approached the Dr to give them two monthly. I still felt wretched and were unable to function so the Dr has refered me to a neurologist.

I suffer with various autoimmune conditions and feel the B12 deficiency is linked. Still feeling awful and knowing it will be a long time before seen by a neurologist I decided to buy my own B12 and inject.

I have put myself on another loading dose for two weeks injecting myself every other day. I find after an injection symptoms get worse then improve for a few hours. It doesn't last but it's still early days.

Once I have finished the loading dose I shall inject weekly as at present it is trial and error. My Gp wasn't happy about my self injecting but my question to her was how was I supposed to cope whilst waiting to see a consultant if she wasn't prepared to give the injections more frequently ?

I was frightened of enduring further neurological manifestations because of my Drs ignorance so took matters into my own hands. I feel you are asking some very valid questions I just wish I could answer them for you.

[palmier]

The numbers I've come across, from various sources, are that an estimated 15 % of a 1000 mcg cyanocobalamin injection is retained, and that an estimated 1 % of a sublingual is absorbed. Retention appears to be better for smaller amounts, so possibly most of what is absorbed from a sublingual is also retained.

The body contains up to 5-6 mg of b12, normally 2-4 mg. To compare, five 1000 mcg cyanocobalamin injections seem to add only 0.75 mg to body stores, far from 'filling it up.'

If 1 % of the 5000 mcg sublinguals is absorbed and most of that retained, it could add something like 0.35 mg a week to the body.

As you say, there is a huge uncertainty as to what is actually absorbed and retained in each individual, but it seems possible that a daily 5000 mcg sublingual could add more per week (0.35 mg) than a weekly 1000 mcg cyanocobalamin injection (0.15 mg) .

1000 mcg Hydroxycobalamin injections, which are standard in the UK, are better retained than cyano, estimated 30 %, so a traditional Brittish loading regime with six 1000 mcg hydroxycobalamin injections might add something like 1.8 mg to the body storage.

I don't know if retention is also affected by how short the time is between doses. Perhaps lowered for frequent injections?

[Gambit62 Administrator]

If you have a B12 absorption problem that means that will also affect your ability to utilise any stores that you have in your liver because the mechanism for releasing the stores uses bile to deliver them to the ileum to be reabsorbed but an absorption problem means this process doesn't properly and most/all of the B12 will actually pass down through the gut where some may be absorbed passively but most will just end up going down the pan so to speak.This means you are reliant upon the amounts sloshing around in your blood from the injection. The reason why some people seem to find that they need much more frequent injections etc isn't understood - there could be a number of mechanisms involved and the PAS has been sponsoring some research based around what happens in the gut.

Personally I found that I didn't start to get better until I was using a nasal spray frequently so you aren't alone in responding better to supplementation than injections but I couldn't tell you what the science is behind that - just that the metabolism of B12 obviously isn't as straight forward as some would think ... probably genetics as there are a lot of genes involved in the metabolism of B12 so there are going to be a lot of potential combinations and different outcomes as a result - however genetics is off topic for this forum so will leave it there.

[charks]

I take oral B12 and responded so well to it I have never bothered with injections. And I had quite a severe case of B12D. I ended up in A&E. But I do take the liquid form and little and often during the day. But you touched on a subject that intrigues me. After it has been depleted does the liver ever store B12 again? I have been on B12 now for over a year but still have to take it daily or I start crashing. I am still running on empty. Will this ever change?

[Soulquest]

You all are so wonderful to reply. Words cannot express how much I appreciate everyone's insight. This is a lonely and scary journey.

SIgNi and JillyMo- sounds like we are in similar places/early days. I will be watching your posts closely with interest and wish you speedy improvements. My folate tested normal as did my iron. My omega is very low but I tried taking fish oil and it makes me really sick. I have terrible gastritis/bile reflux.

As for sublinguals, when I take too much I get painful acne and itchy skin. I know this is a small price to pay, but I am trying to figure out the right dosage of injections vs sublingual and can't quite yet figure out what does what.

Palmier- Thank you for the absorption stats. This is really helpful. I am still unclear as to whether in PA liver stores are useful and whether we can utilize them based on Gambit's reply.

Gambit - I am curious based on your comments about bile if this might be related to my bile reflux which has been hard to manage. All thoughts welcome.

Thanks,

SQ