The rate of neural tube defects had been twice the national average. A daily folate intake of 400 micrograms was selected because that is the recommended daily allowance. The choice is somewhat arbitrary, however, as there is no data indicating that this amount of folate is enough to prevent birth defects. The FDA feared that larger amounts could mask development of macrocytic anemia, which is used for the early recognition of pernicious anemia in older people who might eat large amounts of products enriched with folate. None of the subjects was taking a folate supplement in addition to the fortification.
Fortification of foods is nothing new.
The additions of iodine to salt and vitamin D to milk have proven their worth in preventing goiter and rickets. Simeon Margolis , MD, PhD, is professor of Medicine and Biological Chemistry at Johns Hopkins University. N Engl J Med . Associated Press . Cragan JD, Roberts HE, Edmonds LD, et al.