Which form of b12?

[Freezeframe]

I have pernicious anemia and also homozygous MTHFR c667t. Which form of b12 injectables would be best for me. I did not tolerate Methylfolate well so I now take Folinic supplement. Any comments? Thanks

[fbirder]

Taking folinic acid will be no different to taking folic acid when it comes to MTHFR mutations. Both folic acid and folinic acid end up as methylenetetrahydrofolate. It is this which is converted to methylfolate by the MTHFR enzyme.

All forms of B12 are converted to cob(II)alamin as soon as they enter the cell. So all forms of B12 are, from that point onwards, identical.

People with a homozygous C677T mutation will not benefit from taking methylcobalamin instead of cyanocobalamin or hydroxocobalamin. Where they might benefit is by taking methylfolate instead of folic acid (or folinic acid). If you cannot tolerate methylfolate supplements then you could try be your intake of folate in food.

However, there are about 600 million people in the world with a homozygous C677T MTHFR mutation. Very few of them take any form of folate supplement. Their body just makes more of the enzyme.

My post explaining it healthunlocked.com/pasoc/po...

And folinic acid healthunlocked.com/pasoc/po...

[Freezeframe in reply to fbirder]

I was hoping you’d answer my question. So you is Folinic acid as toxic to me as folic acid is considering my MTHFR? My doctor sent a prescription from cyanocobalamin to Methylcobalamin. I am just finishing my load on cyanocobalamin. I don’t know if trying out the Methylcobalamin is going to cause me to over methylate . Does that make sense? Thank you

[fbirder in reply to Freezeframe]

No. Folic acid is not toxic to people with the homozygous C677T MTHFR mutation. Almost 10% of the population have that mutation. If folic acid was toxic to 10% of the population it would have been noticed by now. There would be medical journals warning of it. But there aren't. There are just lots of clickbait websites spreading misinformation in an attempt to make money.

Cyanocobalamin is just as good as, if not better than, methylcobalamin. ncbi.nlm.nih.gov/pmc/articl...

Some people have an adverse reaction to injecting methylcobalamin. It doesn't seem to have anything to do with MTHFR but may have something to do with COMT.

23andMe are (one of??) the biggest genetic testing companies. They make more money if more people get tested. Here is what they said about MTHFR

Based on the existing data, scientists at 23andMe have concluded that people should not interpret their genotypes at the common MTHFR variants as having an effect on their health. In order for a connection between a genetic variant and a health condition to be considered real and clinically meaningful, well-run scientific studies need to show convincing and consistent evidence for that association. As statements from multiple scientific and medical organizations indicate,[14] [15] that is currently not the case for the common MTHFR variants.

blog.23andme.com/health-tra...