Epidemiology studies have consistently shown that prenatal vitamins taken by mothers-to-be can protect their children from developing brain tumors. But new research from the Brown School at Washington University in St. Louis suggests that high levels of one of those nutrients – folic acid – may actually be detrimental to children at high risk for tumors. The study, published in the August Nutrition and Cancer, was conducted by Dr. Kimberly Johnson, assistant professor at the Washington University Brown School with a secondary appointment in the department of pediatrics at the Washington University School of Medicine.