You may be looking at your supplement label and seeing folate measured in units of "mcg DFE". DFE stands for Dietary Folate Equivalents. DFE is a new way to measure folate metabolism which is now required by the FDA on all supplement labels. The amount of folate is in your products has not changed.
Please also note that the mcg of folate is still listed on the label, along with converted mcg DFE.
The Food and Nutrition Board established these conversion factors for mcg folate to mcg DFE folate:
- 1 mcg food folate = 1 mcg DFE
- 1 mcg folate from fortified foods or dietary supplements consumed with foods = 1.7 mcg DFE
The Food and Nutrition Board made this change to folate measurement (DFE) to reflect the higher bioavailability of supplemental folic acid compared to food folate, however, be careful when dissecting this statement. The FDA considers all supplemental forms of folate, including both folic acid and methylfolate, to be equivalent in potency. However, bioavailability does not always mean utilization: educate yourself around Dr Lynch's research in folate metabolism and folic acid.*
Folic acid, a man-made version of folate that is found in breads, cereals, supplements all over the world. Though it is preferred by the body ("higher bioavailability"), it is not utilized efficiently. Dr Lynch states "Since humans cannot convert folic acid effectively, the excess leads to high amounts of what is known as unmetabolized folic acid in the blood". Though many people take folic acid to increase blood folate levels, they end up with an excess amount of folic acid, and can still have a folate deficiency according to Dr Lynch. Folic acid can even block folate receptors, as it is preferred by the body's receptors over folate, potentially causing or exacerbating folate deficiency.*
For more information on folic acid versus methylfolate, read Dr Lynch's article Folic Acid Side Effects.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.