Iron deficiency and hair loss

Iron deficiency may cause hair loss. The three major causes of iron deficiency anemia are:

• Iron loss from chronic or excessive bleeding. Long-term (chronic) bleeding is the most common cause of iron loss that leads to iron deficiency. Other conditions or events that result in large amounts of blood loss may also lower iron levels to the point where anemia develops. Causes of iron deficiency that are related to blood loss include:
  • Bleeding in the digestive tract, often due to ulcers and inflammation of the stomach (gastritis). This is the most common cause of iron loss in men. Both men and women over age 60 are at an increased risk of digestive tract bleeding.
  • Pregnancy. Blood loss during and after birth may cause a woman to become iron-deficient, which may result in anemia or hair loss.
  • Menstruation. Excessively heavy periods (menorrhagia) can cause an iron deficiency in women, especially when combined with other factors, such as inadequate iron intake.
  • Severe injuries that cause significant blood loss.
• Decreased ability to absorb iron. Medications that reduce stomach acids may cause iron absorption problems. Conditions that may decrease your body's absorption of iron include:
  • Total or partial removal of the stomach (gastrectomy).
  • Lack of stomach acid (achlorhydria).
  • Total or partial removal of the small intestine.
  • Chronic diarrhea.
• Insufficient iron intake. Some people develop an iron deficiency because they do not get enough iron in their diets. Most people's nutritional needs can be met by eating a balanced diet that includes foods high in iron, such as meats.

Low iron can be detected by laboratory tests. For more information, see the topic Iron Deficiency Anemia.