- In the United States, folic acid can be found in foods with mandatory or voluntary fortification, or in supplements. All products labeled as “enriched” are required by the U.S. Food and Drug Administration to be fortified (mandatory fortification) with folic acid, in addition to other micronutrients. The dietary labels on these products must specify that folic acid is included as an ingredient.
- Researchers currently estimate that in the United States, people consume about 140 micrograms (mcg) of folic acid each day from mandatorily fortified foods.
- Voluntarily fortified foods, such as some ready-to-eat cereals, can be fortified with up to 400 mcg of folic acid in each serving.
- In the United States, supplements containing folic acid generally have 400 to 800 mcg of folic acid per dose, but doses up to 1,000 mcg are allowed without a prescription.
- The amount of folic acid consumed from mandatorily fortified foods alone (about 140 mcg each day, on average) occurs at much lower levels than the amount consumed from supplements containing folic acid (about 400 to 1,000 mcg from each dose) or from voluntary fortification (400 mcg from each serving).
- No scientific studies exist that show that supplements containing other forms of folate [such as 5-methyltetrahydrofolate (5-MTHF)] can prevent neural tube defects.