Why are some foods fortified with folic acid?

Folic acid is the man-made form of an important vitamin called folate.  Folate has been shown to help prevent a group of serious birth defects known as neural tube defects.  Neural tube defects, such as spina bifida, involve the incomplete closure of the spinal column. 

Because the neural tube forms soon after conception, women need to have an adequate amount of folate in their diets before becoming pregnant.  Unfortunately, most women consume only about half of the 400 micrograms of folate that's recommended.  That's why many common foods, such as breads, pastas, rice, and ready-to-eat-cereals have been fortified with man-made form, folic acid.

According to Becky Gorham, a registered dietitian at the USDA/ARS Children's Nutrition Research Center and an instructor with Baylor College of Medicine in Houston, the 400 micrograms (mcg) folate recommendation applies to all adults, not just women of childbearing age.  A slice of fortified bread has about 40 mcg of folic acid, while fortified ready-to-eat cereals contain between 100 mcg to 400 mcg per serving. 

Because too much folic acid can mask a vitamin B12 deficiency that can lead to nerve damage, Americans are advised not to exceed 1000 mcg (100 mg) of folic acid in vitamin supplements and fortified foods per day.

Folic acid fortification may benefit more than developing infants.  It's also thought to help protect against heart disease by aiding in the control of a by-product of protein metabolism called homocysteine.

Folate/Folic Acid