The reason I take B12 as a supplement is unrelated to this - I have MTHFR mutation and as such I need to take methyl folate (methylated B9). Apparently this form of B9 absorbs better if it’s combined with the methylated form of B12 (methylcobalamin)

I guess if it will keep my hair color longer that’s a nice side effect!

> Apparently this form of B9 absorbs better if it’s combined with the methylated form of B12 (methylcobalamin)

B9 and B12 are interdependent. When the body uptakes cobalamins, the ligands are pulled off and replaced with ligands sourced from other processes. IIRC in the case of methylcobalamin, the methyl group is pulled off and replaced with a methyl group that’s moved over from methylfolate via a riboflavin-dependent reaction. Been a hot minute since I looked into this so I may have some details incorrect.