Iron deficiency is a leading cause of anemia worldwide: the World Health Organization estimates that about half of the 1.62 billion cases of anemia are due to iron deficiency. Groups at higher risk include pregnant women, infants and young children, women with heavy menstrual bleeding and frequent blood donors. Iron deficiency anemia develops when iron stores run out and red blood cell production is impaired.
Common symptoms
Fatigue and weakness
Difficulty concentrating
Digestive upset
Lower exercise or work capacity
Trouble regulating body temperature
Weaker immune function
Restless legs, which are linked with low iron stores
At-risk groups
Menstruating women, especially those with heavy periods
Pregnant women (the RDA rises from 18 to 27 mg a day)
Infants and young children, especially babies born early or small
Vegetarians and vegans (plant iron is absorbed less well than heme iron)
Frequent blood donors
People with digestive conditions such as celiac disease, ulcerative colitis or Crohn's disease, or who have had stomach or bowel surgery
People with cancer or heart failure
When to see a doctorOngoing tiredness, weakness or trouble concentrating, especially in one of the groups above, is a reason to ask for a blood count and ferritin test. Do not begin iron supplements without testing first: extra iron is harmful when stores are normal, and iron interacts with several medications.