The objective of this study was to assess the impact of shared caregiving on the iron and folate status of infants and toddlers reared at home or enrolled in centre-based, independent home or licensed home care. Eighty-eight 9 and 101 <$ (2-29 months) were recruited from Ottawa, Canada. Nutrient intake (24-hr food record corrected for intra-subject variability), height, weight, and head circumference were assessed one month prior to care entry and at 3 and 6 months post-entry. Red blood cell folate (RBCF), hematocrit IHCT), transferrin, and serum ferritin were assessed at the pre-entry and 6-month post-entry visits. Frequency of illness and antibiotic consumption were determined throughout the study. Median intake of nutrients for all subjects exceeded Canadian recommendations (RNIs). However, 34% of subjects consumed < RNI for iron. Of the iron consumed, only 6.6% was heme iron. Five percent and 0% of subjects at pre-entry and 6-month post-child care entry, respectively, had RBCF concentrations indicative of depletion. Seventeen of 79 children at the pre-entry visit and 15 of 70 children at 6-month post-entry had HCT values indicative of anemia. Subjects attending centre-based care were prescribed more antibiotic courses (2.6±0.25) than subjects attending other forms of care (P<0.004). Seventy-five percent of all subjects were prescribed at least one course of antibiotics. Neither iron nor folate status were associated with illness or consumption of antibiotics. In conclusion, infants and toddlers are generally well nourished regardless of child care arrangement; however, iron status remains a concern in this study population. Funded by Health and Welfare Canada.