Iron Nutrition in Schoolchildren of Western Mexico: The Effect of Iron Fortification

In Mexico, food fortification is used as a strategy to combat micronutrient deficiencies. However, little is known about the effects of food fortification in vulnerable populations. This study was carried out in a population of school children believed to be at risk of various micronutrient deficiencies, including iron. The study aimed at determining iron status of children, and identifying and quantifying the sources of iron intake and the presence of relevant enhancers and inhibitors of iron absorption in the diet. The iron status and dietary iron intake was assessed of schoolchildren aged 3–14 years in western Mexico. Hemoglobin, serum ferritin, and transferrin saturation percentages were used to evaluate the iron status in a school-based sample of 762 children. Dietary data were collected from 607 children using semi-quantitative food frequency questionnaires. The overall prevalence of anemia and iron deficiency was 3.7% and 4%, respectively. Iron intake ranged from 1.9 to 3.3 times the recommended daily allowance, with fortified iron accounting for 72% of the total iron intake. Although iron fortification of staples such as maize flour in Mexico for more than a decade most likely contributed to reducing the prevalence of anemia and iron deficiency, the relatively large amounts of iron consumed could eventually lead to problems related to excessive iron intake in some children. Nutritional guidelines for iron fortification in Mexico should be defined and put into practice.