Clinical recommendation	Evidence rating	References	Comment
High-risk infants six to 12 months of age should be given routine iron supplementation.	B	14	Infants are considered high risk if they are living in poverty; are black, Native American, or Alaskan Native; are immigrants from developing countries; are preterm or low birth weight; or if their primary dietary intake is unfortified cow's milk.
Blood donors should take 20 mg elemental iron daily with vitamin C.	C	13, 17, 18	Blood donors lose iron; 20 mg per day replaces lost iron with minimal constipation or gastroesophageal reflux disease; vitamin C potentiates iron absorption.
Patients of either sex who are older than 65 and have iron deficiency anemia should be screened for occult gastrointestinal cancers.	B	30	In a population-based cohort, 9 percent of adults older than 65 years (95% CI, 0.02 to 0.25) had gastrointestinal cancer, and older adults with anemia had gastrointestinal cancer 31 times as often as adults without anemia.
In men and nonmenstruating women younger than 65 years, screening for occult gastrointestinal cancer should be undertaken in the absence of another explanation for iron deficiency.	B	30	In a population-based cohort, 6 percent of adults with anemia (95% CI, 0.01 to 0.16) had gastrointestinal cancer on investigation.
Hemoglobin and ferritin tests are the best for diagnosing iron deficiency anemia.	C	25–27, 29	See Table 4 for likelihood ratios.