DESCRIPTION (taken directly from the application) Helicobacter pylori (H. pylori) infection induces hypochlorohydria/achlorohydria in the stomach. Gastric acid is considered as an important luminal factor in the absorption of food/non-heme iron and many other micro-nutrients, e.g. beta carotene, a provitamin A. It is, therefore, hypothesized that H. pylori infection might be responsible for the iron and vitamin A deficiency in children which is highly prevalent in the third world countries, like India. It is, therefore, proposed in this small grant application to evaluate i) if eradication of H. pylori improves response to supplementation therapy with iron and vitamin A. One hundred and twenty children of ages 3 to 10 years, infected with H. pylori, will be recruited from the outpatient facilities of the B.C. Memorial Children's Hospital in Calcutta (India). This will be a 4 cell case control study where one group (n=30) will receive anti H. pylori therapy + iron and vitamin A supplementation, the second group will receive anti H. pylori therapy + placebo, the third group will receive no anti H. pylori therapy + iron and vitamin A supplementation and the fourth group will receive no anti H. pylori therapy + placebo. Iron status will be assessed by measuring hemoglobin and serum ferritin level while increases of serum retinol level over 20 ug/dL will be considered as an improvement of vitamin A status. RDR test will also be performed to evaluate the vitamin A status. Serology and C urea breath test (UBT) will be used to confirm H. pylori infection. Statistical analyses of the results from this factorial placebo control study are expected to provide adequate and appropriate data to substantiate our hypotheses in this study. This study might be of great public health interest, since iron anemia and vitamin A deficiency are highly prevalent, particularly in the preschool age children, worldwide.