Hemoglobin (Hb or Hgb) is the protein in your red blood cells that carries oxygen. A low hemoglobin count is a below-average concentration of the oxygen-carrying hemoglobin proteins in your blood.
A low hemoglobin count is generally defined as less than 13.5 grams of hemoglobin per deciliter (135 grams per liter) of blood for men and less than 12 grams per deciliter (120 grams per liter) for women. In children, the definition varies with age and sex. The threshold differs slightly between medical practices.
A low hemoglobin count is a commonly seen blood test result. In many cases, a low hemoglobin count is only slightly lower than normal, isn't considered significant and causes no symptoms. A low hemoglobin count can also be caused by an abnormality or disease. In these situations, a low hemoglobin count is referred to as anemia.
A low hemoglobin count is often discovered during a complete blood count test. If your test reveals you have a low hemoglobin count, ask your doctor what this means for you.
Make an appointment if you have signs and symptoms
If you experience signs and symptoms of a low hemoglobin count, make an appointment with your doctor. Signs and symptoms may include:
- Faster than normal heartbeat during exercise or activity
- Feeling short of breath
- Lack of energy during your usual activities
- Pale skin and gums
Your doctor may recommend a complete blood count test to determine whether you have a low hemoglobin count or whether your signs and symptoms are caused by something else.
May 17, 2012
- Schrier SL. Approach to the adult patient with anemia. http://www.uptodate.com/index. Accessed April 4, 2012.
- McPherson RA, et al. Henry's Clinical Diagnosis and Management by Laboratory Methods. 22nd ed. Philadelphia, Pa.: Saunders Elsevier; 2011. http://www.mdconsult.com/books/page.do?eid=4-u1.0-B978-1-4377-0974-2..00032-4&isbn=978-1-4377-0974-2&uniqId=327813426-7#4-u1.0-B978-1-4377-0974-2..00032-4. Accessed April 4, 2012.
- Hussein M, et al. Approach to anemia. Disease-a-Month. 2010;56:449.