The hemoglobin test is often used to check for anemia, usually along with a hematocrit or as part of a complete blood count (CBC). The test may be used to screen for, diagnose, or monitor a number of conditions and diseases that affect red blood cells (RBCs) and/or the amount of hemoglobin in blood.
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What Does Low Hemoglobin Mean? Patient Comments Read 3 Comments Share Your Story Low hemoglobin means that a person's hemoglobin level when measured, is below the lowest limits of normal for their age and sex (see above normal range of values). For example, a 19 year old male would have low hemoglobin if the detected blood value was below 13.6 g/dl. Another term frequently used in place of low hemoglobin is anemia, or the person is described as being anemic. Some of the more common causes of anemia are as follows:
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Hemoglobin is the protein molecule in red blood cells that carries oxygen from the lungs to the body's tissues and returns carbon dioxide from the tissues back to the lungs. Hemoglobin is made up of four protein molecules (globulin chains) that are connected together.
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Higher than normal hemoglobin levels can be seen in people living at high altitudes and in people who smoke. Dehydration produces a falsely high hemoglobin measurement that disappears when proper fluid balance is restored. Some other infrequent causes are high hemoglobin levels are: advanced lung disease (for example, emphysema); certain tumors;
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A low hemoglobin level is referred to as anemia or low red blood count. A lower than normal number of red blood cells is referred to as anemia and hemoglobin levels reflect this number. There are many reasons (causes) for anemia. Some of the more common causes of anemia are:
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A hemoglobin A1c of 6% roughly correlates with an average blood sugar level of 135 mg/dL (milligrams per deciliters) over the previous 3 months. Each 1% increase in hemoglobin A1c above 6% represents an average blood sugar of approximately 35 mg/dL over 135 mg/dL.
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For people without diabetes, the normal range for the hemoglobin A1c level is between 4% and 5.6%. Hemoglobin A1c levels between 5.7% and 6.4% mean you have a higher change of getting of diabetes.
http://www.webmd.com/diabetes/guide/glycated-hemoglobin-test-hba1c
How are hemoglobin levels tested? Hemoglobin levels are measured by a blood test. Hemoglobin, or Hb, is usually expressed in grams per deciliter (g/dL) of blood. A low level of hemoglobin in the blood relates directly to a low level of oxygen. In the United States, anemia is diagnosed if a blood test finds less than 13.5 g/dL in a man or less than 12 g/dL in a woman. In children, normal levels vary according to age. What do high hemoglobin levels mean? High hemoglobin levels could be indicative of the rare blood disease, polycythemia. It causes the body to make too many red blood cells, causing the blood to be thicker than usual. This can lead to clots, heart attacks, and strokes.
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A serum hemoglobin test measures the amount of free-floating hemoglobin in your blood serum. Your doctor may use it to diagnose or monitor hemolytic anemia. A serum hemoglobin test measures the amount of free-floating hemoglobin in your blood serum. Serum is the liquid that is left over when the red blood cells and the clotting elements have been removed from your blood plasma. Hemoglobin is a type of oxygen-carrying protein found in your red blood cells. Normally, all of the hemoglobin in your body is contained in your red blood cells. However, some conditions may cause some of the hemoglobin to be in your serum. This is called free hemoglobin. The serum hemoglobin test measures this free hemoglobin. Doctors usually use this test to diagnose or monitor abnormal breakdown of red blood cells. If you have had a recent blood transfusion, this test can monitor for a transfusion reaction.
https://www.healthline.com/health/serum-hemoglobin
What do low hemoglobin levels mean? Low hemoglobin levels usually indicate that a person has anemia. There are several kinds of anemia: Iron-deficiency anemia is the most common type. This form of anemia occurs when a person does not have enough iron in their body, and it cannot make the hemoglobin it needs.
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what is hemoglobin levels
A low level of hemoglobin is a low level of oxygen.