Here is quote I came across today in paper on diabetes/metformin and B12d:
"Folate administration prior to correcting vitamin B12 deficiency should be avoided because it results into progression and / worsening of the associated neurological manifestations "
This is interesting as it goes against the received wisdom...
Or is it actually saying, only treat folate once B12 supplementation has started? It seems from other papers that high folate levels mask B12d symptoms and is an argument used not to fortify flour et al.
"One recent study indicates that high serum folate levels during vitamin B12 deficiency exacerbate (rather than mask) anemia and worsen cognitive symptoms."
guidelines recommend starting B12 replacement 24-48 hours before treatment with high dose folate. There has been at least one reported case of neurological damage being made worse as a result of starting high dose folate before treatment with B12. It can happen but it is extremely rare.
There has also been some research on fruit-bats that showed that increasing folate levels whilst B12 levels were low caused neurological problems but it is always difficult to assume that what happens in another mammal will be replicated in a human population
A folate deficiency can mask one of the symptoms of a B12 deficiency - macrocytic anaemia. This is only a problem with doctors who believe that macrocytic anaemia is a defining symptom of a B12 deficiency and who, therefore, rule out such a deficiency if there is no macrocytic anaemia present.
There are some people who suggest that treating with high levels of folic acid may exacerbate the neurological problems caused by a B12 deficiency.
The obvious thing to do is for doctors to check for a B12 deficiency before treating a diagnosed folate deficiency - and not by the presence or absence of macrocytic anaemia.
"Care should be taken not to give folic acid (instead of B12) to any patient who is B12-deprived, as this may result in fulminant neurological deficit."
The British National Formulary (Section 9.1.2 Drugs used in megaloblastic anaemias) states
"Folic acid has few indications for long-term therapy since most causes of folate deficiency are self-limiting or will yield to a short course of treatment. It should not be used in undiagnosed megaloblastic anaemia unless vitamin B12 is administered concurrently otherwise neuropathy may be precipitated.
Thanks for the replies, they shed more light on the rather blunt statement I quoted at the top. With some research on here yesterday I picked up that some plp see rising folate as a consequence of supplementing B12, so I guess with additional folate supplementation levels could quickly rise to unacceptable levels. Think I am going to back off the folate supplements for at least the time being.
Thanks again for the replies and other linked items.
There is no reason at all why taking B12 should increase the levels of folate. Indeed, it is well known that a B12 deficiency can cause folate levels to rise because of the folate trap.
I found that to be true. When I took methylfolate before correcting B12 deficiency I had horrible neurological symptoms. I backed it down with Niacin and then increased my B12 and later was able to tolerate methylfolate.
I had the same issues. I was wondering what you think would be the B12 Level that someone should have if they are sensitive to the methylfolate, before they may be able to tolerate the methylfolate?
What I would suggest (I amnot a dr just real life experience) is getting the methyl b12 injections until you see some improvement in symptoms. I would then take small doses of methylfolate to start. I would break the capsule open to build my way up. Have niacin on hand (the flushing kind) as if you have a neurological reaction the high flush niacin will “mop up” the excess methylfolafe and back it down.
Admin note: response edited to remove reference to named individual
I don’t know if methyl vs hydro is the same just that I proved on bloodwork a reverse of b12 deficiency with the methyl injections. This doctor you reference says that folic acid and methylfolate have the same effect, but this pubmed study shows otherwise ncbi.nlm.nih.gov/m/pubmed/2.... I haven’t studied the niacin in-depth but it did help me in my case with pretty immediate results when I had too much methylfolate.
Same here. I was self-injecting B12 every week, and still had B12 deficiency symptoms by the end of the week. My serum B12 levels was very high, but it felt like the B12 wasn't getting into my cells.
I started looking for B12 transport problems, and found a study showing that folate can impair B12 transport in some people. ncbi.nlm.nih.gov/pubmed/277.... I don't have the exact genetic variation in the study, but perhaps I have another variation on the B12 transporter gene, or on another gene involved.
When I reduced my daily methylfolate from 800mcg to 400mcg, I was able to go twice as long between B12 shots.
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