Recently a number of people have asked about methylfolate brands that are not Metafolin. This site may have some answers about it. As only the L-methylfolate is active and these others are a mix people were wondering about effectiveness. A paper list on this site suggests that the inactove form might actually block the active L-methylfolate, so another form of paradoxical folate deficiency. In any case he is into testing for these and appears well on his way in research on the polymorphisms. http://mthfr.net/mthfr-doctor-consult-with-dr-ben-lynch/2011/09/10/ http://www.healthegoods.com/mthfr-test.html Elsewhere on the site problems with some methylfolates are mentioned and articles.