Blood loss can also cause anemia – whether it’s because of excessive bleeding due to injury, surgery, or a problem with the blood’s clotting ability. Slower, long-term blood loss, such as intestinal bleeding from inflammatory bowel disease (IBD), can also cause anemia.
Anemia sometimes results from heavy menstrual periods in teen girls and women. Any of these factors will also increase the body’s need for iron because iron is needed to make new RBCs