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Causes of Anemia: Contributing Factors for Low Hemoglobin

causes of anemia feature image

Anemia is the most common blood disorder, affecting more than 3 million Americans. (Source)  Are you familiar with the causes of anemia? If not, this post may give you a better understanding of this prevalent condition and how it is manifested in the body.

Your Blood & Red Blood Cells

Whole blood & causes of anemia

Whole blood is comprised of red blood cells, white blood cells, platelets and plasma, as illustrated in this graphic from Encyclopedia Britannica. In this post, we are going to focus on the red blood cells. They contain an iron-rich protein called hemoglobin, which carries oxygen throughout the body. When your blood does not contain sufficient amounts of healthy red blood cells, or when these cells do not function properly, you have anemia.

How do you know the status of your red blood cells? Through specific and commonly ordered blood tests, your hemoglobin and hematocrit (a measure of the space that red blood cells take up in your blood) levels can be obtained. Both of these tests are generally included in a complete blood count (CBC). Low levels of hemoglobin or hematocrit are a sign of anemia.

Causes of anemia - normal hemoglobin chartCauses of anemia - normal hematocrit chart

According to the Iron Disorders Institute, your healthcare provider may also want to test serum ferritin, which indicates the amount of iron stored in the body. This is important because it helps distinguish between iron deficiency anemia and anemia of chronic disease (for which taking iron supplements can be harmful). Also, serum iron and iron-binding capacity (IBC, UIBC or TIBC) tests may be run. These measures are used to calculate transferrin-iron saturation percentage (TS%), a measure of iron in transit in the serum. (Source)

Symptoms of Anemia

Anemia is often a silent condition, which can go undiagnosed for too long. If you are experiencing symptoms as indicated here, you should have a discussion with your doctor.

  • Chronic fatigue
  • Pale complexion
  • Dizziness
  • Headaches
  • Weakness
  • Shortness of breath
  • Sensitivity to cold
  • Pica
  • Restless legs
  • Rapid heartbeat
  • Irritability
  • Numb or cold hands and feet
  • Changes in stool color

Causes of Anemia/Low Hemoglobin Levels

  • Your body is not producing enough red blood cells
    • Iron deficiency, some medications, cancer, hypothyroidism, lead poisoning, chemotherapy, toxic chemical exposure, kidney disease, viral infections, bone marrow functioning issues, vitamin deficiency or nutrient absorption issues (folate, vitamins B6 and B12), radiation, autoimmune disorders, enzyme deficiencies, Crohn’s disease, etc.
      • Can include aplastic, iron deficiency and apstic anemias
      • Iron deficiency anemia is a risk for vegetarians due to the elimination of meat (a major source of iron) from their diets
      • Vitamin B12 deficiency anemia as well an iron deficiency anemia are risks for vegans because they avoid all animal products
      • Medications that can cause anemia include cancer chemotherapy drugs, some antibiotics (penicillin, chloramphenicol), antihistamines, antifungals, and medications for transplants, HIV and malaria
  • Your body is destroying its red blood cells faster than it can make them
    • Enlarged spleen, sickle cell anemia, porphyria, a genetic condition called thalassemia, vasculitis, etc.
      • Generally termed hemolytic anemia
  • You experience excessive bleeding (your body can’t replace lost red blood cells fast enough)
    • Heavy menstrual bleeding, digestive tract bleeding (stomach ulcers, IBD), urinary tract bleeding, wound bleeding, blood clotting issues, frequent blood donation, etc.
      • Generally termed iron deficiency anemia


The most common of these causes of anemia/low hemoglobin levels are: poor nutrition, ulcers, kidney issues, rheumatoid arthritis, trauma or surgery-related blood loss, and bone marrow disorders (including chemotherapy and radiation-related). Hemoglobin levels can also be slightly lower during pregnancy due to an increased demand for red blood cells and hemoglobin, and is also normal for some individuals.

It is important to note that anemia is a common problem among older adults, especially anemia of chronic disease. In this case, although there is enough iron in the body, the bone marrow cannot incorporate it into the red blood cells. This type of anemia can be associated with cancer, chronic renal failure, collagen vascular disease, chronic infection, and medications. Seniors are also at a greater risk for anemia due to increased medication usage and nutritional deficits that occur when they lose significant amounts of weight, even if vitamins are administered. (Source)

Many types of anemia are not preventable, but you may be able to avoid this condition by eating a healthy diet that includes foods that are high in iron, folate, and vitamins B6 and B12. This post highlights the essential nutrients and best foods to eat for building blood. You may also check out this article for more ideas: Iron Rich Recipes for Energy and Healthy Blood.

Treatment options for anemia are based on the cause, so it is important to heed the advice of your healthcare professional. If left untreated, anemia can result in various health concerns, including those related to the heart, pregnancy, and even death.

Have you suffered with anemia? If so, how was it diagnosed? Share your story in the comments below. You may help one of our readers with your experience!