Hi all, I've been diagnosed as 'not absorbing B12' but am not sure why. I didn't test positive for IF antibodies (although I understand that's not accurate) but think my stomach acid is probably low. Anyway, that's not my question for now. I'm self-injecting B12, was weekly and now once every 3 weeks seems to be OK. The peripheral neuropathy I was experiencing is much better. It's taking longer with the low energy but I think I am seeing slow improvements. I've been trying to read and understand the whole B12 absorption thing. This is where I'm confused: B12 injections bypass the need to absorb it and go straight into the bloodstream to be stored in the liver. I understand that the liver is able to store large quantities of B12 over many months. So how come we need to inject so often? (I see there are very variable frequencies for different people's needs and I know there is no way I can wait the 3 months the GP is offering). Is the stored B12 not bio-available? And if not why not? Are there any resources I can read around this?
PS It's been so helpful being part of this group- so far I've just been reading and not commenting but it's been really helpful and has stopped me feeling so isolated in this. So thank you all.
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Search on enterohepatic circulation of B12. You're correct that your body is storing B12 in the liver, most likely perfectly normal and in a person without PA the body would normally recycle this B12. There is maybe 2 to 3 years of B12 stored here. However, the body recycles this B12 from the liver through your common bile duct into the duodenum (first part of small intestine). It is normally a small trickle amount rather than on-demand. Once in the duodenum the B12 follows the normal absorption process through the digestive system. In other words it must bind with Intrinsic Factor which allows it to be absorbed in the Terminal Ileum (the last part of small intestine). For those with PA and lacking IF this recycling is broken and the B12 from the liver as well as that from recently ingested food just passes through unabsorbed.
For those with PA the only stores we have available is that currently in our blood serum. A very short lived storage hence frequent injections. I note that injection frequencies vary amongst individuals as we are all different. Also depends on what stage of disease we are each in. Some inject EOD, some weekly, some monthly, just listen closely to your body, Shhhhh! You'll learn to notice little barely perceptible things, maybe a pain in that right toe, a momentary fleeting stabbing pain in your foot, a little wobble in your walk, or a headache, fatigue, brain fog. All of these may be signs that your cells are yelling at you like a newborn wanting to be fed! 🙂. The trick is to time these incidents and inject a few days before they happen. I personally have settled on every 6 to 7 days. But sounds like you're listening to yourself though.
That's a great question. Firstly, liver stores of B12 being unavailable does not apply to all those with "B12 deficiency" but rather only those with the autoimmune condition Pernicious Anemia where we cannot absorb B12.
To answer your question, the half-life of injected B12 in human serum has been measured to be ~6 days. Meaning that half of what you inject is excreted or used by the body in that time. Another way to look at it is if one injects 2000 mcg of B12 then 6:days later there will be 1000 mcg remaining. And so in after 6 more days or day 12 there will be 500 mcg remaining. This continues for 5 or 6 half-life or 30 days. I'm not sure but this is quite possibly why doctors in US typically prescribe once monthly B12 injections for those with PA. Note that although essential and critical to life, the human body needs only a miniscule amount of B12, about 72 mcg per month to function properly. Also the half-life of B12 varies a bit from individual to individual and is influenced by sex, age, health, BMI, etc.
I've found no studies or data that supports 3 month injection interval is OK for those with PA.
I happen to inject 2000 mcg of methylcobalamin about every 6 to 7 days only based on how I am feeling.
Thank you. I'm so scared. I'm having horrible neurological symptoms and neuropathy and worried I'm going to die like this. Starting to even question if b12 is my issue
I noticed you joined in October of this year. If that's about when you were diagnosed and started supplementing B12 through injection AND you're still having neurological and peripheral neuropathy then your current frequency of three weeks may not be enough. If it were me, just a suggestion of course as I'm not a doctor, I'd try at least weekly again or even EOD. There is a short window to heal nerve damage before it may become permanent. It also can take a year or more to heal these nerves after start of B12 therapy.
In fact, through my experience, continued nerve damage does not just stop when you start injecting. It really depends on how severely deficient you were when diagnosed. Nerves become exposed and damaged when myelin sheath becomes eroded. This is the protective sheath that covers the nerves of which B12 is required to maintain. As this sheath is being healed and repaired with this elixir of life the nerves remain exposed and damaged can continue to occur while this healing is taking place.
As Enuffisenuf said "it takes time."
Keep your injections frequent until improvement stops... Maybe a year, maybe longer. Also know your dose.
YES, it is scary. Trust me no one on this forum wasn't scared of "what the heck is happening to me!" At the start of treatment. Scared is OK. Just try and stick with it and take little victories as they slowly happen.
Like "This can't possibly be it, I'm still getting worse. Everyone else started getting better, so maybe there's something else. Something they've missed or not tested for and identified yet."
Luckily, I was later sent to an ENT specialist, who told me that I quite clearly had a B12 deficiency. That I was doing the right thing by self injecting frequently, and that I would have to be patient and not give up, as it would take a very long time, but that I would improve.
Shordae - keep going. JanMoon - you are right : the people here are really supportive and can keep you on track through this experience. Rexz - Thanks !
I've been having constant tingling and numbness all over my body since January. It's been a year now are you saying it's permanent? Also, I haven't done the injections. I only did a couple, but I had to stop because everybody in these groups kept telling me that my ferritin was too low. My ferritin was 20 the last time checked. They said if I inject it will cause me more issues so I haven't.
Hi Shordae, my reply was mixed up between you and JanMoon. But I went back and looked at your bio and I apologize as I had assumed you had been diagnosed with Pernicious Anemia and B12 deficiency? My response was really geared towards that.
I really can't say if your situation is permanent or not? With little information I only offer my experience... I was severely deficient in B12 back in Jan 2020 to the point of collapsing. I was started on weekly B12 injections for two months then monthly. Then about 6 months into my treatment the entire right side of my body suddenly went completely numb. I couldn't walk. My B12 injections were moved back to weekly and it took me many months to recover my peripheral nerves and we'll over a year for other neurological symptoms. Today I am mostly recovered. I do have some residual nerve damage in my right hand and right foot not to much though. No more tingling just a bit of numbness. My neurological symptoms are recovered except for a condition called acalculia where I can no longer do simple math in my head. For the first time in my life I now rely on spreadsheets and calculators. Today I function pretty good and I am now hike often. I offer this to you not to scare you but to let you know that things can improve. The important thing is to get a proper diagnosis so you are treated properly. I might also add that no to people are the same and much depends on the severity of B22 deficiency, duration of deficiency, and many other factors.
Regarding B12 and iron deficiency.... They are independent of each other. Although some of those with PA will have both the causation is different. B12 deficiency is caused by Parietal Cell Antibodies and Intrinsic Factor Antibodies (IF). IF being required to absorb B12. Hence injections. Iron malabsorption on the other hand, for those with PA, is caused by very low levels of gastric acid (hypochlorhydria) or zero gastric acid (achlorhydria) which I have. So the treatment of B12 def and iron def are independent of each other. Although one does need to treat megaloblastic or macrocytic anemia for "normal" red blood cells to transport iron. If you've a confirmed diagnosis of Autoimmune Gastritis/PA and iron deficiency with or without anemia then most likely oral supplements will not help but rather iron infusions are necessary. Again the importance of a diagnosis.
I'm not a doctor for sure so best I can advise is to take information you glean from this site, including mine, have a conversation with your doctor and ask, ask, ask.
Sorry to jump in late here, but I saved this post and was rereading it. I thought low stomach acid alone (without antibodies to IF or parietal cells) could cause b12 deficiency?
MorningMist , you're exactly correct! I apologize for confusing that.
Yes, irregardless of PA/AIG one can be B12, iron and other macronutrient deficient with very low (hypochlorhydria) or no (achlorhydria) gastric acid. Proper gastric acid pH is necessary to convert pepsinogen to pepsin and properly break down food, especially protein. Into smaller and smaller pieces where digestion can take place. This is where B12 cleaved and binding with R-protein takes place (in the stomach). IF although produced in the stomach follows The chyme (partially digested food) into the duodenum where the R-protein is cleaved and IF then binds with the B12. The IF-B12 bound molecule will then travel to the Terminal Ileum to be absorbed. It's all quite a complex dance and fascinating to think how all this was designed!
Hello,As others have said it takes time. It may be hard but you have to try not to stress. Your body is undergoing alot. I know how you feel. I felt like it was my last as well 😌
I try to stay positive and not tell alot of people bc it takes up energy having to explain to everyone and then slightly irritating bc they may perceive it as something that's not dire.
Advocate for yourself! Take care of you! Have some self care routines, delete negativity as much as possible. Like others I increase my dose based on how I feel. I couldn't survive on weekly more is needed for me. Know your body and keep fighting!!
I am not on injections. I have been constantly having tingling and reduced sensation all over my body since last January.. I started to inject a few times, but then the B12 group told me that my ferritin was too low so now I haven't. Don't really sure what to do. I'm taking iron tablets at a lower dose because that's what I tolerate.
Sorry, I'm confused. You have low serum B12 and low ferritin. So both B12 Pernicious Anemia and iron based Anemia?Who advised you to stop B12 injections?
Either could cause the symptoms you are having. You need oxygen round your system.
If you have been diagnosed with Pernicious Anemia you need the injections regularly for life.
Your troubles here are muddled in someone else's post. It might be worth doing a separate post, stating any blood level statistics for clarity.
As far as I can find out you can inject vitamin B12, when your ferritin is low and it may help improve your iron absorbtion. But as I said please start your own thread to get the collective and more expert knowledge.
I'm newly certified having autoimmune gastritis, blood test was positive and the scope confirmed the damage and yes PA did rear its ugly head which is how I got diagnosed. You seem really well versed with all of this confusing PA mess of contradictory advice and findings, so would be interested on you opinions.
I am now at the test dummy phase of injections (every 3 months) which I do not believe will be sufficient.
I started taking sublingual 1,200mcg Mecobalamin midway through my last monthly shot because I felt my energy waning I stopped them a week before my last bloods performed the day before my last monthly shot to try to not skew the results. the results were that I had borderline B12 sufficiency at 280 (sufficiency > 300) and my active b12 at 62 (sufficiency > 40).
I will go down the self injection route if it required. At the moment I'm just testing the waters.
To throw a spanner in the works of understanding my low energy my ferritin levels dropped from 182 to 40 in 2 months (pre/post B12 injections, should be 30-400, I suspect the levels were not correct to start with, perhaps PA showed a false high level). I'm now on iron supplements with added folate and taking vitamin c to aid absorption. The part of my gut that absorbs iron is good so should be no issues there.
To add to the confusion of my low iron levels, I previously worked in IT for over 25 years and am now working my ass off as a domestic cleaner which is fast paced and I'm sweating my ass off anywhere between 2 -5 hours each day. Not a lifelong career, but good enough to get back into the world.
I am totally shocking my system in every way so it is hard to figure out what is happening and why! On a bad day over the last few years a slow 10 minute walk would push me, so I am clearly much better, but never want to go back to my previous zombie functional state.
So, after this long spiel, a few questions.
Why would daily sublingual B12 not work? If only 1% was absorbed into my blood from the mucus membrane it would make 12mcg per day which should suffice.
Is active B12 a good measure of absorption of B12 and if so, what should it be for someone with PA. My only measures are from my last bloods at 62 (should be > 40), previously they were undetectable and have not and will not be automatically measured unless my regular B12 results fall below sufficient (> 300) so have no reference how they have changed over time?
Is there an optimal ferritin level for someone with PA?
Is there an optimal folate level for someone with PA?
Autoimmune gastritis being an autoimmune condition, does that mean that it at times it could go into remission and your gut could heal somewhat? (new to this stuff, aiming high for my wishes, don't want to get any symptoms down the track)
Lastly, am I bat shit crazy?
Be honest, especially with the last question. This disease is frustrating in that general doctors have no idea and it is difficult to know if you are finding the right information and making the correct decisions for yourself.
I would appreciate any insights that you may have and will forward many positive vibes and karma to you in appreciation.
There's a lot to unpack here so I've got to digest..maybe not the best word considering the topic, how about absorb, nope not good either OK just read through again! 😜 So will answer all your questions in a bit. But all very good questions and your curiosity and ability to ask those puts you a bit ahead of the game.
Let me start for now by answering your last question first... Emphatically YES, you are bat shit crazy! As evidenced by joining the bat shit crazy club here with the rest of us. 😂
I'll eread and respond more whilst I have my morning coffee ☕
Lovely to be amongst kindred folk. Thankyou or your diagnosis, although I suspect I have had this mentioned before. Oh, I forgot to order my cute bat earrings, true.
I will look at your answers tomorrow, don't rush yourself, I need to get rest its almost 1am. Work at 10am, need rest.
Why would daily sublingual B12 not work? If only 1% was absorbed into my blood from the mucus membrane it would make 12mcg per day which should suffice.
If you take that absorption figure as true, that might be enough to maintain normal stores but if you're already deficient, you can't heal massive amounts of damage on so little B12. Personally I don't have any faith in sublinguals at all but for people with less severe deficiency it might work - BUT even if there's a chance it does for them, since there's no accurate way to monitor levels and quite often reversal or healing symptoms are similar to damage symptoms, how would we know for sure it's working?
Remember, a lot of people with malabsorption also are deficient in iron and folate. So once we get these three musketeers treated, they're all going to start using each other up. 12mcg per day might be enough for Joe Bloggs, but is it enough for someone who needs B12 available to heal nerve damage due to B12D, plus heal blood cells, increase oxygen around the body, etc.? And then the maintanence dose on top of it?
Is there an optimal ferritin level for someone with PA?
Is there an optimal folate level for someone with PA?
I was told ferritin over 50 ng/L min and over 100 optimal. Folate in the teens.
Lastly, am I bat shit crazy?
Once you've healed some more from B12D you'll look back and wonder how you were even functioning in your right mind (many of us weren't 😀) no you are a perfectly sane individual, you're just stuck in a bat shit crazy body that doctors don't understand!
Here's my take... for those with PA they don't work. Even for those without I am not sure they work through being absorbed sublingually or through the skin in skin patches. For those with B12 def due to being vegan certainly sublingual will work but only through the swallowing of the B12 Saliva mixture and absorption through the normal Binding with IF and terminal ileum process. Here's a repost of a post I made several months ago...
I've researched this also and there are no evidentiary studies that remotely suggest skin patches work for B12. The B12 molecule is the biggest and baddest molecule on the block by far. That's why it is the only vitamin that is given such special VIP treatment by our body through the digestion process. Much like a super tanker needing many tugboats to guide it into port. Our port is the terminal ileum, the last part of the small intestine where our designers installed special receptors for the Intrinsic Factor (IF) that is bound to the B12. The receptors do not recognize the B12 molecules by themselves with IF.
Most molecules that do work with patches are around the 150 to 250 molecular weight. I think nicotine is around 150 or 160'ish so these are easily absorbed through the skin. However, the B12 molecule weight is over 1,200.
Same issue with B12 sublingual or nasal sprays. These claim to work, and I do believe they work as a supplement but not absorbed through the mucous membrane under the tongue or the sinus mucosa. I mean, logically, what makes us think that B12 could more readily be absorbed through the skin, under the tongue, or sinus better than anywhere along the highly absorptive small intestine?!
So, why does sublingual SEEM to work for some??? My, I think, rather valid theory, is that no B12 is actually being absorbed under the tongue. However, unlike digesting a piece of meat where your digestive juices in the stomach first must cleave the B12 molecule and then immediately it gets bound with an R protein that has followed it down with your saliva ready to do its job. The R protein in the saliva is the first VIP escort that keeps this very special, prima-donna, B12 molecule from being damaged by the digestive juices within the stomach. The IF will bind with the B12 after the R protein is cleaved in the duodenum. Well, with many B12 deficient people that still have IF and thus some of any form of supplementation will work. This also includes those with AIG that haven’t progressed to an advanced stage of Pernicious Anemia. What the sublingual benefit may do is that as the B12 is dissolved under the tongue, think lots of saliva and R protein, the B12/R protein may bind in the mouth before it gets to the stomach thus protecting more of the B12. But think, virtually ALL of the B12 you would dissolve under your tongue eventually gets swallowed so the uptake mechanism of the B12 in the terminal ileum is the same.
If one pays close attention to the studies, they are not clear whether the participants are those with PA and IFaB or PCab or just B12def. This piece of information is critically missing so it's important to review the methods and participants selection in any study you read. One place to look for a valid study is the nutritional supplementation requirements of those who have undergone a total gastrectomy. These studies clearly include a study pool with zero IF and zero gastric acid (achlorhydria) so they have all the same micronutrient absorption issues that one with an advanced state of AIG/PA will have.
This is a smattering of my research and conclusions I have made from that. Consider this my educated opinion and nothing more.
Optimal Ferritin for those with AIG/Pernicious Anemia, and hypo- or achlorhydria…
Autoimmune Gastritis and achlorhydria create a double whammy for iron malabsorption. The proper pH of gastric acid is required for you to properly absorb iron. Then to exacerbate a low iron level is the fact that with Gastritis/chronic inflammation your body’s immune system sequesters its available iron. It does this normally when it is fighting some pathogen or virus as these need iron to reproduce. So, your immune system sequesters iron in an attempt to kill any invading virus. For those with AIG then just serum Ferritin is not a valid marker, and Ferritin should be kept at 100 ng/mL, where the normal range is 30 to 400 ng/mL. Make sure you have complete iron panels done with blood tests not just Ferritin.
See my posts here and you’ll find some more detail discussion and links.
My doctors and I are keeping my Ferritin above 100ng/mL and when it drops below that I get an iron infusion. I am at an end stage of this disease and have zero oxyntic mucosa Parietal cells and stomach acid (achlorhydria)
Optimal Folate…
Those of us with AIG/PA have no absorption issues with Folate. I do take a B12/Folate sublingual daily…not for the B12 but rather just the Folate. I measure my serum Folate rarely but just try and keep it at a normal level of 2-20 ng/mL.
Hope this is helpful. Sorry for the delay in responding.
Having P.A.means that your stored B12 is unavailable to you, because you have no Intrinsic Factor .
You will need to inject B12 often enough to keep B12 symptoms at bay . Glad to hear that you have found a routine that is helping you.
we do not know why patients require differing regularity of injections. I know people who find 3 monthly fine , and I know someone who has to inject twice a day .., and others anywhere in between .
A great deal of research needs to be done for this “Cinderella “ condition
Most of the medical profession are not well informed about it . We have to find our own salvation I’m afraid .
For neuropathy I took 15 mg of L-Glutamine powder from Klaire Labs 2x a day and my neuopathy disappeared. I haven't taken it in few years and the neuropathy has not returned. Ask your doctor before trying anything like this. Just thought it might help .
With PA, we lack intrinsic factor. You can think of that as the delivery truck that picks up the B12 in the digestive track and delivers it into the body. Our trucks are no longer working. The mechanism for recycling B12 goes through the liver. But it requires the truck (intrinsic factor) to get it back into circulation again. So for people with PA, the recycling is not working either. The IF anti-body test has a very high false negative rate. If it is positive, you have PA. But lots of people with PA get a negative on that test, but it does not mean you do not have PA. You say your peripheral neuropathy is better. That is a strong sign you have PA. I would encourage you to keep up every other day injections until it is gone. Then choose an interval where you do not get symptoms back. I get tingly toes in 3 weeks so I inject once per week. Very best wishes!
Injections are active and stay in the blood, I believe. B12 stored in the liver is inactive; you need adequate IF to convert it, I think.
The NHS test could show say a total B12 value of 200 (can't remember the actual units!) so active B12, which is what you need, could be as low as 20 (10% of 200) or as high as 60
Danger level is lower than 30 to 40, I think. So an NHS test lower than 400 could mean imminent danger.
One thing we know is that the recycling of B12 (the entero-hepatic recirculation) does not function in someone who has PA so there is a loss of up to 5mcg per day through bile which would normally be mostly recovered (~1 mcg ordinarily being lost per day).
I have found it difficult to locate good resources on the mobilisation of stored B12. It's important to understand that B12 is not only stored in the liver - up to 30% of the bodys B12 is in muscle.
Resources such as the "Nutrient Metabolism" book from Martin Kohlmeier state that :
"There is a lack of information on the processes that govern mobilization of stored 5' -deoxyadenosylcobalamin".
The majority (>50%) of B12 is stored in the liver (1–3% methylcobalamin; 60–80% adenosylcobalamin) with total stores reaching up to 5 mg (ref1). 30% is stored in muscle (ref2).
ref1 :E. Laird, A.M. Molloy, in Reference Module in Biomedical Sciences, 2014 available online at sciencedirect.com/topics/bi...
ref2 : Messina M, Messina V. The Dietitian’s Guide to Vegetarian Diets. Gaithersburg, MD: Aspen Publishers, Inc., 1996
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