Objective: To evaluate the protective role of breastfeeding against diarrhea in children younger than one year of age in the city of Feira de Santana, Brazil, in 2001.
Methods: A cross-sectional study was carried out. Questionnaires were applied to mothers by 104 university students on the national vaccination day in 44 health units (71.0%) selected by simple stratification. 2,319 children were evaluated (24.3% of the estimated population). The prevalence ratio was calculated and considered significant if p< or =0.05 with a 95% confidence interval.
Results: Diarrhea occurred in 11.6% of the sample, with greater frequency after the sixth month (63.3%). The chance for presenting diarrhea was 64% higher in children younger than six months who were not breastfed vs. breastfed children (p<0.02). When compared to the children who were exclusively breastfed, the chance for presenting diarrhea increased to 82% in children who were not breastfed (95% CI 1.11-3.01).
Conclusions: Breastfeeding and exclusive breastfeeding were a protective factor against diarrhea in the first six months of life.