Low Hemoglobin


What is hemoglobin?

Hemoglobin is a substance in red blood cells that makes it possible for blood to transport (carry) oxygen throughout the body. (Hemoglobin is what gives red blood cells their color.)

What are normal hemoglobin levels?

Normal hemoglobin levels for men is between 14.0 and 17.5 grams per deciliter (gm/dL); for women, it is between 12.3 and 15.3 gm/dL.

Who is most likely to develop iron-deficiency anemia?

Anyone can develop iron-deficiency anemia, although the following groups have a higher risk:

  • Women, because of blood loss during monthly periods and childbirth
  • People over 65, who are more likely to have diets that are low in iron
  • People who are on blood thinners such as aspirin, Plavix®, Coumadin®, or heparin
  • People who have kidney failure (especially if they are on dialysis), because they have trouble making red blood cells
  • People who have trouble absorbing iron

How can I know if I have low hemoglobin?

Your healthcare provider can perform blood tests to check your hemoglobin level and to tell if you have anemia. The type and number of blood tests will depend on what type of anemia is suspected.

Possible Causes

What happens when someone has low hemoglobin?

If a disease or condition affects the body’s production of red blood cells, the hemoglobin levels may drop. Fewer red blood cells and lower hemoglobin levels may cause the person to develop anemia.

What is anemia?

Anemia is a blood disorder that occurs when there is not enough hemoglobin in a person's blood. When a person develops anemia, he or she is said to be "anemic." There are several different types of anemia. Some types cause only mild health problems, while others are much more severe. Each type of anemia comes from one of these factors:

  • The body cannot make enough hemoglobin.
  • The body makes hemoglobin, but the hemoglobin doesn't work right.
  • The body does not make enough red blood cells.
  • The body breaks down red blood cells too fast.

What causes anemia?

Your body uses iron to make hemoglobin. A lack of iron in the body is the most common cause of anemia. This is called iron-deficiency anemia. If you don’t get enough iron, your body cannot make hemoglobin. Factors that can lower your body's stores of iron include the following:

  • Blood loss (caused by ulcers, trauma, some cancers, and other conditions; and, in women, during monthly periods)
  • An iron-poor diet
  • An increase in the body's need for iron (in women during pregnancy)

What are the symptoms of anemia?

There are a number of symptoms that occur in all types of anemia, including:

  • Feeling tired
  • Trouble breathing
  • Dizziness
  • Headache
  • Feeling cold
  • Weakness
  • Pale skin

Care and Treatment

How is anemia treated?

To treat anemia, the healthcare provider must first learn what is causing it (a poor diet or a more serious health problem). In that way, the provider can treat the anemia and the cause. Iron-deficiency anemia is treated by increasing the amount of iron the patient gets, either with iron supplements taken by mouth or by eating more foods that are high in iron.

What foods are high in iron?

The iron in food comes from two sources: animals (found in various meats and fish) and plants (found in certain vegetables and in iron-fortified foods such as breakfast cereals).

The following foods are good sources of iron:

  • Oysters
  • Kidney beans
  • Beef liver
  • Tofu
  • Beef (chuck roast, lean ground beef)
  • Turkey leg
  • Whole wheat bread
  • Tuna
  • Eggs
  • Shrimp
  • Peanut butter
  • Leg-of-lamb
  • Brown rice
  • Raisin bran (enriched)
  • Molasses

Last reviewed by a Cleveland Clinic medical professional on 02/02/2018.


  • National Heart, Lung, and Blood Institute. Anemia. (https://www.nhlbi.nih.gov/health-topics/anemia) Accessed 2/15/2018.
  • National Heart, Lung, and Blood Institute. Your Guide to Anemia. (https://www.nhlbi.nih.gov/files/docs/public/blood/anemia-yg.pdf) Accessed 2/15/2018.
  • American Society of Hematology. Anemia. (https://www.hematology.org/education/patients/anemia) Accessed 7/1/2020.
  • American Association for Clinical Chemistry/Lab Tests Online. Hemoglobin. (https://labtestsonline.org/understanding/analytes/hemoglobin/tab/test/) Accessed 2/15/2018.

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