B12 is water soluble and does not cause neuropathy. It was a error by the original poster. As for methyl vs cyano, it depends whether you have the genetic fact

B12 is water soluble and does not cause neuropathy. It was a error by the original poster. As for methyl vs cyano, it depends whether you have the genetic factors that would benefit or not from methyl groups. In my case I wouldn't benefit so I don't take the methyl form and instead take the hydroxy and adeno forms. Cyano is useless. Needs multiple steps in the liver to convert.