Statements like folic acid is ineffective in people with MTHFR “mutations”, it blocks methylation, can’t be absorbed, or is unsafe, are exaggerations and not entirely accurate. This variant merely lessens the efficiency of conversion. What’s important when discussing folate (as folic acid, m...
Cycloserine: Reduces folic acid absorption and reduces serum folate levels. Dihydrofolate Reductase Inhibitors (DHFRI): DHFRIs block the conversion of folic acid to its active forms, and lower plasma and red blood cell folate levels. DHFRIs include aminopterin, methotrexate, pyrimethamine, triamterene...
Folate (found in dietary sources) and folic acid (found in supplements) are both biologically inactive as consumed, and must be converted to the metabolite 1-methylfolate (MTHF), which is biologically active and able to cross the blood-brain barrier. MTHF acts as a regulator of a critical ...