Gastrectomized rats develop anemia and osteopenia, and ingestion of fructooligosaccharides leads to an increase in iron absorption and promotes recovery from anemia in iron-deficient rats. Laparotomized (sham-operated control) rats and totally gastrectomized (Billoth II) rats, in groups of 14 each, were fed a control diet without fructooligosaccharides or a diet containing fructooligosaccharides (75 g/kg of diet) for 6 wk. All rats received an intramuscular injection of vitamin B-12 every 2 wk. Tail blood was collected every week for determination of hematocrit and hemoglobin concentration. At the end of the experiment, the rats were killed and the femur and tibia were collected for measurement of bone mineral density (BMD). The hematocrit, hemoglobin concentration, hemoglobin regeneration efficiency, and BMD of both femurs and tibias were significantly lower in gastrectomized rats fed the control diet than in the other three groups. Dietary fructooligosaccharides prevented anemia and osteopenia in totally gastrectomized rats.