Can Crohn's Disease Cause Anemia?

Crohn's disease can be exhausting. But tired feelings may go beyond the stress of dealing with a chronic illness. Over a third of people with Crohn's disease may have anemia: low levels of red blood cells or hemoglobin, a protein in red blood cells that helps transport oxygen throughout the body, which causes symptoms like fatigue and weakness.

Both iron and vitamin B12 are needed to make red blood cells, so deficiencies in either of these nutrients can lead to anemia.

Crohn's disease can cause anemia in a few different ways:

  • Bleeding in the digestive tract. Blood vessels in the digestive tract can rupture when Crohn's-related ulcers and fissures penetrate beneath the inner mucosal layer of the intestines. This blood loss can lead to iron-deficient anemia.
  • Long-term inflammation and swelling. The inflammation associated with Crohn's disease may prevent your body from absorbing iron as well as it should, which can lead to iron-deficient anemia.
  • Vitamin B12 deficiency. Anemia in Crohn's disease can also be unrelated to iron levels. Other potential causes of low hemoglobin include a vitamin B12 deficiency from poor absorption in the intestines. 

Fatigue and weakness are the best-known symptoms of anemia, but signs of anemia can also include shortness of breath, cold hands or feet, and unusual cravings, such as for ice or dirt.

How is anemia treated in Crohn's disease?

The best way to treat iron deficiency or anemia in Crohn's is to address the underlying disease, but your doctor may also recommend iron supplements or adding more iron to your diet. 

However, iron supplements can come with complications and side effects, particularly for those living with Crohn's. Crohn's disease may interfere with the body's ability to absorb the iron. Oral iron supplements may also cause nausea or constipation – not ideal for those already experiencing Crohn's symptoms.

If you're concerned about anemia symptoms, talk with your doctor about the best treatment options for your individual case.

You may also consider adding additional high-iron foods to your diet. Food sources of iron include:

  • Red meat (two to three servings per week)
  • Dairy: Cheddar cheese, cottage cheese, milk
  • Fish: Oysters, sardines
  • Poultry: Chicken, Turkey
  • Fruits: Cantaloupe, raisins
  • Nuts: Cashews, pistachios
  • Vegetables and beans: Broccoli, peas, mushrooms, potatoes, spinach, tomatoes, chickpeas

Crohn's disease is different for everyone, and you may have found that avoiding certain foods helps your Crohn's symptoms. Consider working with a dietician for help balancing your nutritional needs with your Crohn's disease symptoms. 

Clinical trials for Crohn's disease

Existing Crohn's disease treatments don't work for everyone. Clinical trials are researching potential new options – answer a few questions to find research opportunities near you.