Folate is involved in neurotransmitter synthesis and critical enzymatic reactions throughout the body. By depleting excess homocysteine, folate benefits cardiovascular health and nervous system function. Those who take ordinary folic acid supplements, however, may not be experiencing its full spectrum of effects. This is because folic acid is itself not biologically active, but its biological importance is due to its active form called 5-methyltetrahydrofolate (5-MTHF) after its conversion to dihydrofolic acid in the liver. 9 Research shows that in a large proportion of the population, genetic dihydrofolate reductase enzyme deficiencies limited the conversion of folate to 5-MTHF, leaving many vulnerable to low blood 5-MTHF levels (and higher than desired homocysteine). A more useful approach is to take the bioactive folate 5-MTHF directly, which has been declassified as a drug and is now available as a dietary supplement. 5-MTHF has been shown to dramatically raise red blood cell folate levels10 compared with foli