Anemia | Causes & Risk Factors


What can cause low iron levels?

A number of things can cause low iron levels in your body:

Diet. You may have low iron levels if you don’t eat enough foods high in iron. This is mostly a problem for children, young women who follow “fad” diets and people who don’t eat meat.

Inability to absorb iron. The iron in your food is absorbed by the body in the small intestine. Diseases that affect your small intestine’s ability to absorb nutrients, such as Crohn’s disease or celiac disease, may cause low iron levels in your body. Some foods or medicines, including milk, antacids or stomach acid-lowering medicines, also can prevent your body from absorbing iron.

Growth spurts. Children younger than 3 years of age grow so fast that their bodies may have a hard time keeping up with the amount of iron they need.

Infants who drink cow's milk in the first year of life are at risk for iron deficiency anemia. It’s the most common dietary cause of iron deficiency in infants. Cow’s milk does not have enough of the iron infants need to grow and develop. Do not give cow's milk to your infant in the first year of life. Breastfed infants who do not eat iron-rich foods like iron-fortified cereal or take an iron supplement after the fourth month of life are also at risk of iron deficiency anemia.

Toddlers (12 to 24 months of age) who drink a lot of cow's milk, have a diet low in iron, or already had iron deficiency as an infant are also at risk.

Pregnancy. Women who are pregnant or who are breastfeeding need more iron than women who are not pregnant or breastfeeding. That's why pregnant women often are tested for anemia and why they need to eat more iron-rich foods or take a daily iron pill.

When you're pregnant, your body makes more blood to share with your baby. You may have up to 30% more blood than when you’re not pregnant. If you don’t have enough iron, your body can't make the red blood cells that it needs to make this extra blood.

The following may increase your risk of anemia during pregnancy:

  • Vomiting a lot from morning sickness
  • Not getting enough iron-rich foods
  • Having heavy periods before pregnancy
  • Having 2 pregnancies close together
  • Being pregnant with twins, triplets or more
  • Becoming pregnant as a teenager
  • Losing a lot of blood (for example, from an injury or during surgery).

If you are pregnant and are not getting enough iron, you are at risk of developing iron-deficiency anemia.

Blood loss. Heavy periods may cause low iron levels in women. Internal bleeding, usually in the digestive tract, also can cause blood loss. A stomach ulcer, ulcerative colitis, cancer, or taking aspirin or similar medicine for a long time can cause bleeding in your stomach or intestines.

Genetic diseases. If you have sickle cell disease or thalassemia, your body has trouble producing healthy red blood cells, which can lead to anemia. You’re also at risk of passing these diseases on to your unborn baby. If you or someone in your family has one of these diseases, talk to your doctor about how to prevent or treat anemia while you’re pregnant.

What causes normocytic anemia?

Normocytic anemia can be a problem you were born with (called congenital) or it can be caused by an infection or disease (called acquired).

The most common cause of the acquired form of normocytic anemia is a chronic (long-term) disease. Chronic diseases that can cause normocytic anemia include kidney disease, cancer, rheumatoid arthritis and thyroiditis. Some medicines can cause you to have normocytic anemia, but this does not happen often.



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Written by editorial staff

Reviewed/Updated: 02/14
Created: 01/96