Folic acid fortification of foods may reduce the incidence of the most common type of kidney cancer and a type of brain tumors in children, according to new study at Washington University in St. Louis. Incidence reductions were found for Wilms' tumor, a type of kidney cancer, and primitive neuroectodermal tumors, a type of brain cancer.

Since 1998, the U.S. Food and Drug Administration has mandated fortification of foods with folic acid because earlier studies show that prenatal consumption of folic acid significantly reduces the incidence of neural tube defects in babies.

The study, published in the current issue of Pediatrics, examined the incidence of childhood cancer pre- and post-mandated folic acid fortification. This study found that Wilms' tumor rates increased from 1986 to 1997 and decreased thereafter, which is an interesting finding since the downward change in the trend coincides exactly with folic acid fortification. PNET rates increased from 1986 to 1993 and decreased thereafter. This change in the trend does not coincide exactly with folic acid fortification, but does coincide nicely with the 1992 recommendation for women of childbearing age to consume 400 micrograms of folic acid daily.The study involved 8,829 children, from birth to age four, diagnosed with cancer.