Cow's milk consumption and childhood anemia in the city of Sao Paulo, southern Brazil

Objective To evaluate the influence of the consumption of cow milk on the risk of anemia during childhood in the city of Sao Paulo. Methods We have studied a probabilistic sample (n=584) of under five children living in the city of Sao Paulo, southeastern Brazil, between 1995 and 1996. Anemia (hemoglobin < 11g/dl) was diagnosed using capillary blood obtained by fingertip puncture. The cow milk content and the density of heme and nonheme iron in the child diet were obtained using 24-hour recall questionnaires. Multiple linear and logistic regression models were used to study the association between cow milk content in the diet and hemoglobin concentration or risk of anemia, and included statistical control for potential confounders (age, sex, birthweight, presence of intestinal parasites, family income, and mother schooling). Results The prevalence of anemia was 45.2% and the mean contribution of milk to the total caloric content of the children diets was 22.0%. The association between milk consumption and risk of anemia remained significant, even after considering the dilutive effect of milk consumption on the density of iron in the diet, thus indicating a fect of milk on the absorption of the iron present in the other foods possible inhibitor ingested by the child. Conclusions The relative participation of cow's milk in the child's diet showed a significant positive association with risk of anemia in children between ages six and 60 months, regardless of the density of iron in the diet.