Outside | In: Iron-Deficiency Anemia

Anemia — or a lack of healthy red blood cells — is the most common blood disorder in the United States, according to the American Society of Hematology. The most common form of anemia is called iron-deficiency anemia, which occurs when your body doesn’t have enough iron. As a result, your bone marrow is unable to produce an adequate number of red blood cells.

There are various reasons your body might be running low on iron, and figuring out what’s causing your deficiency is a crucial first step, says Sioban Keel, MD, a hematologist and associate professor of hematology and medicine at the University of Washington School of Medicine. Commonly, an iron deficiency occurs if you’re losing too much blood or your body is unable to properly absorb iron from food.

• Have heavy menstrual periods
• Are pregnant
• Have a gastrointestinal disease like celiac disease, ulcerative colitis, or Crohn’s disease
• Have a peptic ulcer
• Eat a vegetarian or vegan diet

Your body needs iron for many functions, including the maintenance of healthy skin, hair, nails, and more. But this mineral’s main task is to help produce red blood cells, which contain a protein called hemoglobin that is responsible for transporting oxygen from your lungs to the rest of your body.

Here’s how your body uses iron:

1. Iron is absorbed from food in the GI tract before being released into the bloodstream.
2. In the bloodstream, iron attaches to a protein called transferrin and is delivered to the liver.
3. Iron is stored as ferritin in the liver until it is released to make new red blood cells in the bone marrow.

• Healthy Red Blood Cells Hemoglobin gives red blood cells their bright red color. When red blood cells pass through the lungs, oxygen molecules attach to the hemoglobin. From there, red blood cells transport oxygen to cells in your muscles and other vital organs and tissues.
• Anemic Red Blood Cells When iron levels are too low, red blood cells become smaller and don’t contain as much hemoglobin. When that occurs, less oxygen is transported around the body, causing fatigue and other symptoms.

• Food Eating legumes, dark leafy greens, and red meat can give your body a boost of iron, but keep in mind that “the body absorbs heme iron, which is found in meat, about three times better than it can absorb elemental [or non-heme] iron, which is found in plants,” says Dr. Keel. According to the National Institutes of Health Office of Dietary Supplements, people who don’t eat meat, poultry, or seafood need almost twice as much iron as those who do eat meat.
• Supplements Both over-the-counter and prescription iron supplements contain elemental iron, says Keel. She recommends taking the pills with orange juice because vitamin C can boost your body’s absorption of iron.
• IV injections If you have trouble absorbing iron or can’t tolerate a supplement, your doctor may recommend intravenous iron injections on a periodic basis.

• 1 serving of iron-fortified breakfast cereal: 100 percent of the recommended daily value⁺
• 3 ounces (oz) of oysters: 44 percent*
• ½ cup of white beans: 44 percent
• 3 oz of dark chocolate (45 to 69 percent cacao solids): 39 percent
• ½ cup of boiled lentils: 17 percent
• ½ cup of spinach: 17 percent
• ½ cup of tofu: 17 percent
• 3 oz of sardines: 11 percent*
• ½ cup of chickpeas: 11 percent
• 3 oz of beef: 11 percent*
• 3 oz of chicken: 6 percent*
• 1 large hard-boiled egg: 6 percent

⁺National Institutes of Health Office of Dietary Supplements, Iron, March 2018

*Heme iron