Your blood vessels are the body's superhighway. Blood races through more than 50,000 miles of vessels, delivering nutrients to cells and hauling waste products away from them. One of the blood's most vital passengers is oxygen. Oxygen binds to hemoglobin, a protein in red blood cells, and is carried to cells throughout the body. Anemia occurs when hemoglobin does not carry enough oxygen to cells. There are several possible causes. Sometimes the body has too little iron, which is essential to the formation of hemoglobin. Deficiencies of vitamin B-12 or folic acid can also cause anemia. Sometimes there are not enough red blood cells, which can result from ulcers or other undetected sources of blood loss. And sometimes the body simply demands more iron for growth: Pregnant women and growing toddlers are at increased risk of anemia. People who are anemic can have headaches, dizziness, difficulty breathing, fatigue and they may feel cold. Anyone who has such symptoms can find out, through a simple blood test, whether some form of anemia is to blame. To keep that superhighway moving, we have to make sure that the blood is doing its job.

A complete blood count (CBC) is an important tool in gauging overall health. The test measures the volume of red blood cells and hemoglobin in the blood to make sure that both are adequate, and records the size, shape and color of red blood cells. When iron deficiency is causing anemia, the red blood cells are smaller and paler. When vitamin B-12 deficiency is the culprit, the red blood cells are larger, and there are fewer. If anemia is detected, doctors will do further tests to rule out cancer, ulcers, chronic kidney disease and a few inherited disorders that require serious medical interventions. However, iron deficiency causes most cases of anemia, and usually can be corrected with oral iron supplements as well as dietary changes. Iron-rich foods include kidney beans, beef, tofu, peanut butter and brown rice. For most people with anemia, the solutions involve just a few small changes that make a big difference in how they feel.

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