Hemoglobin is a protein in your red blood cells. Your red blood cells carry oxygen throughout your body. If you have a condition that affects your body’s ability to make red blood cells, your hemoglobin levels may drop. Low hemoglobin levels may be a symptom of several conditions, including different kinds of anemia and cancer.
Hemoglobin is a protein in your red blood cells. Your red blood cells carry oxygen throughout your body. Oxygen powers your cells and gives you energy. A low hemoglobin level may be a sign of several conditions, including different kinds of anemia and cancer.
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If a disease or condition affects your body’s ability to produce red blood cells, your hemoglobin levels may drop. When your hemoglobin level is low, it means your body isn’t getting enough oxygen, making you feel very tired and weak.
Normal hemoglobin levels are different for men and women. For men, a normal level ranges between 14.0 grams per deciliter (gm/dL) and 17.5 gm/dL. For women, a normal level ranges between 12.3 gm/dL and 15.3 gm/dL. A severe low hemoglobin level for men is 13.5 gm/dL or lower. For women, a severe low hemoglobin level is 12 gm/dL.
Healthcare providers diagnose low hemoglobin by taking samples of your blood and measuring the amount of hemoglobin in it. This is a hemoglobin test. They may also analyze different types of hemoglobin in your red blood cells, or hemoglobin electrophoresis.
Several factors affect hemoglobin levels:
Your bone marrow produces red blood cells. Diseases, conditions and other factors that affect red blood cell production include:
Your bone marrow constantly produces red blood cells. Red blood cells live about 120 days in your bloodstream.
Some factors that affect that lifespan include:
Healthcare providers treat low hemoglobin by diagnosing the underlying cause. For example, if your hemoglobin levels are low, your healthcare provider may do tests that reveal you have iron-deficiency anemia. If that’s your situation, they’ll treat your anemia with supplements. They may recommend you try to follow an iron-rich diet. In most cases, treating the underlying cause of anemia will bring the hemoglobin level up.
Many things can cause low hemoglobin, and most of the time you can’t manage low hemoglobin on your own. But eating a vitamin-rich diet can help maintain your red blood cells. Generally speaking, a balanced diet with a focus on important nutrients is the best way to maintain healthy red blood cells and hemoglobin. Here are some suggestions:
If you have a disease or condition that affects your hemoglobin levels, you should call your healthcare provider anytime your symptoms worsen.
A note from Cleveland Clinic
If you have blood test results that show your hemoglobin level is lower than normal, it means you have fewer red blood cells doing essential work — that is, carrying oxygen throughout your body. A low hemoglobin level may not be a cause for alarm. Many things affect hemoglobin levels. If your test results show low hemoglobin levels, your healthcare provider will explain why you have this symptom, what it means and how it will be treated.
Last reviewed by a Cleveland Clinic medical professional on 05/04/2022.
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