Methylcobalamin is an incomplete form of B12 and must be supplemented for pernicious anemia or B12 deficiency, according to a 2015 article in the European Journal of Nutrition. This information is available on wikipedia.org. Please spread this information widely.
Methylcobalamin incomplete: ... - Pernicious Anaemi...
Methylcobalamin incomplete
Thank you but could you give an exact reference/link to the article in the EJN.
Not quite sure what is meant by 'an incomplete form of B12' as I'm not sure what a complete form of B12 would be. There are many different forms of B12.
There will be many on this forum who have found methyl works well for them but others (myself included) who have found that it really doesn't do everything that they need - but there could be a number of reasons for this. Others find that it really doesn't work for them. Genetics may play a part in this but the biochemistry of B12 is extremely complex and there are a lot of things that B12 is being used for. At the cell level processes tend to use either methyl or adenosyl forms - depending on the process.
There have been cases in which some people are unable to convert methyl to adenosyl but there is no real information on what the incidence of this problem might be.
Methycobalamin has been more effective for me than transcobalamin. The citation is: Thakkar, K. & Billa. G. (2015-01-01). Treatment of vitamin B12 deficiency - methylcobalamin? cyanocobalamin? hydroxocobalamin? - clearing the confusion. Euro. J. Clinical Nutrition, 69(1), 1-2. Is the issue conversion or is it different metabolic functions of the different forms?
transcobalamin is a transport mechanism for B12 that is created in the body - it isn't something that you can be treated with.
The forms of B12 used to treat a B12 deficiency (and other conditions) are: cyanocobalamin, hydroxocobalamin, methylcobalamin and adenosylcobalamin. These are listed in order of stability. The last two are the metabolic formats that are used at the cell level in different processes.
Thank you all for prompt and careful responses. I look forward to fuller discussion at wikipedia but also hope that the nutrition scientists who wrote the original article will clarify and specify the basis of their conclusion. Is conversion the issue or is it that methylcobalamin and adenosylcobalamin have distinct metabolic functions?
This is part of a letter from Wilhelmina Reitsema in 'Rapid responses' to the BMJ research document on B12 deficiency, that might help explain the differences:
" There are two active forms of the B12 enzyme in the human cell. First, Methylcobalamin acts as a co-enzyme for the conversion of homocysteine to methionine. Methionine then acts as a methyl-donor to a great number of reactions that need a methyl group, including the synthesis of myelin, serotonin, dopamine, noradrenalin, DNA and phospholipids.
Second, Adenosylcobalamin is a co-enzyme for the conversion of L-methylmalonyl-CoA into succinyl-CoA which feeds into the citric acid cycle."
"Is it important which form is used in treatment? In most people, it does not matter. They can convert cyano- and hydroxo-cobalamin into the active forms needed. However, I have recently reported a case in which it did matter. The severe vitamin B12 deficiency, including dementia and psychosis, responded to treatment with high dose oral methylcobalamin, but not to equally high dose oral hydroxocobalamin. [1]"
1. Rietsema WJ. Unexpected Recovery of Moderate Cognitive Impairment on Treatment with Oral Methylcobalamin. Journal of the American Geriatrics Society 2014;62(8):1611-12 doi: 10.1111/jgs.12966[published Online First: Epub Date]|. "
I was advised on the forum to take vit B12 and methylcobalamine and this worked well for me as when I had a full blood count recently my VitB result came back as 923 just outside NHS norm with the note 'is patient taking supplementation' so it worked well for me as a hypothyroid person. I am not sure what my result should be so please advise. Many thanks.
Hi Taminaone. There is no such thing as a 'correct' serum B12 level. If you have been supplementing with B12, then your B12 level will likely be above the top end of the reference range...so in this sense, your B12 level would be one that is expected, following supplementation.
The real issue with serum B12 levels is when they are low and indicative of a B12 deficiency which should, of course, be treated.
So...the right amount of B12 is the amount that gets rid of your deficiency symptoms and makes you feel well. However, this is complicated by your hypothyroidism, since there are a lot of cross-over symptoms between B12 deficiency and hypothyroidism: it might be difficult to tell which symptoms are due to what 😀.
Just a little confused about your reference to taking B12 AND methylcobalamin. Methylcobalamin is one form of vitamin B12, the others being cyanocobalamin (not often prescribed in the UK, though some do use it), Hydroxocobalamin, and adenosylcobalamin.
Some people find that one form works better, for them, than others but this is a matter of trail and error and individual 'preference'. Some also take more than one type of cobalamin, finding that each individual cobalamin works to elliaviate different symptoms (again, it's a matter of trail and error).
Really pleased that you are getting some relief from what you're taking.
Please post again if you need any further advice....lots of people here to help, if needed 😀.
Take care X
Are very many people finding success with using adenosylcobalamin?
Hi Hopefull2016. Sorry, not sure. One of the lesser used, I think, so read about it rarely..I do recall someone once saying that if gave them relief from one of their symptoms, but can't remember which. Oops, Foggyme!
If you use Hydroxocobalamin and do not have a problem with methylation, this is converted to Methyl and Adeno during the methylation process - so you get it anyway!
I think (but not sure) that adenosylcobalamin is also derived from Methyl during methylation (unless you have a problem with methylation).
I think I've just talked myself into thinking that only people with a methylation problem take adenosylcobalamin - but I could be entirely wrong about that - and perhaps someone will see this,post and reply 😀. On the other hand, it may be that some people find it relieves symptoms that the other cobalamins don't do anything for. Hmmm.....
I'd be really interested to see a definitive answer to your query - why don't you put up a seperate post (so more people see it) and we can see what people say 😀😀.
if wikipedia is wrong, anyone can edit it and make changes. Im not the expert in methyl but if there is one on here i suggest they propose a change to the methylcobalamin page.
Ah ha....so indeed, Foggyme!!
Thanks fbirder 👍😀.
Afterthought - is there some kind of conversion process going on (rather than methylation) and can you point me to some reading so that I can clarify myself?🙃🙃
I use adenosyl lozenges - main effect is controlling bladder weakness - still need to go urgently at times but at least I make it to the loo before the gates open (sorry tmi) ... and I don't have so much of a problem with sneezing. It works quite well for me with mood as well.
methyl works okay with some of the neuro problems.
overall hydroxo does the most - just that I seem to need a bit of help with a couple of symptoms round the edges.
Actually quite a few people use adenosyl sublinguals (or even injections) and some with good results. Loads of sublinguals with that available as well, usually called 'co-enzym' or dibencozide. It has it's function. It is said that for the neuro methyl would be better and for the 'rest' adenosyl (fatigue) There are also sublinguals with both forms (like from NOW) Or just take hydroxo and get them both like that