Subject(s)

Food, Fortified , Nicotinic Acids , Nutrition Disorders/prevention & control , Riboflavin , Zea mays , Black or African American , Arm , Black People , Child , Child, Preschool , Darier Disease/epidemiology , Diet , Humans , Leg , Niacinamide/urine , Pyridones/urine , Riboflavin/urine , Serum Albumin/analysis , Skin Diseases/epidemiology , South America , Stomatitis/epidemiology