Bone Marrow

Bone marrow is the soft, fatty tissue inside of the bones in your body. Bone marrow contains cells that produce blood cells and platelets and it is responsible for making billions of new blood cells each day.


What is bone marrow?

Bone marrow is the soft, fatty tissue inside of bone cavities. Components of your blood including red and white blood cells and platelets form inside of your bone marrow.


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What does bone marrow do?

Bone marrow makes nearly all the components of your blood. It's responsible for creating billions of red blood cells daily, along with white blood cells and platelets. Bone marrow also stores fat that turns into energy as needed.

Can you live without bone marrow?

Bone marrow makes the components of your blood that you need to survive. Bone marrow produces red blood cells that carry oxygen, white blood cells that prevent infection and platelets that control bleeding. The absence of bone marrow can be fatal since it's an essential part of your body.


Can I donate bone marrow?

Yes, bone marrow and the healthy cells it produces are necessary for humans to live. Often, cell mutations harm healthy bone marrow cells, and a bone marrow transplant would be a treatment option for people diagnosed with blood cancers like leukemia.

A bone marrow transplant takes healthy cells from a donor and puts them into your bloodstream. The donor’s cells help your body grow healthy red and white blood cells and platelets.


Where is bone marrow located?

There are three parts to the anatomy of your bones: compact bone, spongy bone and bone marrow. Compact bone is the strong, outer layer of your bones. Spongy bone makes up the ends of your bones. Bone marrow is in the center of most bones and in the end of spongy bones in your body. Bone marrow and blood vessels fill cavities in your bones, where they store fat and stem cells and produce blood cells that make your whole blood.


What does bone marrow look like?

Bone marrow is a spongy, soft tissue that resembles a jelly or jam that you would spread on toast. It comes in two colors, red and yellow. Bone marrow fills the cavities of your bones and holds cells that create red and white blood cells and platelets, which make whole blood. The color of red bone marrow is the result of red blood cell production.

What are the two types of bone marrow?

There are two types of bone marrow in your body, which are characterized by their color. Your body holds just under 6 lbs. (about 2.5 kg.) of red and yellow bone marrow.

  • Red: Red bone marrow produces blood cells (hematopoiesis). Stem cells in your red bone marrow (hematopoietic stem cells) create red and white blood cells and platelets, all of which are components of your whole blood.
  • Yellow: Yellow bone marrow stores fat. There are two types of stem cells in yellow bone marrow (adipocytes and mesenchymal stem cells). These cells preserve fat for energy production and develop bone, cartilage, muscles and fat cells for your body.

Red bone marrow makes up all of your bone marrow until about age seven. Yellow bone marrow gradually replaces red bone marrow as you age.

What is bone marrow made of?

Bone marrow is made of stem cells. These stem cells make red bone marrow, which creates blood cells and platelets for your blood. Yellow bone marrow consists mostly of fat and stem cells that produce bone and cartilage in your body.

Conditions and Disorders

What are common conditions and disorders that affect bone marrow?

Directly targeting bone marrow is leukemia, which is a blood and bone marrow cancer. Leukemia forms when a cell mutation occurs in your bone marrow and mutated cells multiply out of control, reducing the production of healthy, normal cells.

Since bone marrow is the foundation for the creation of blood cells, blood-related conditions often are the result of abnormally functioning bone marrow. These conditions include:

  • Multiple myeloma: Your body produces cancerous plasma cells in your bone marrow.
  • Aplastic anemia: Your bone marrow doesn’t produce enough blood cells.
  • Polycythemia vera: Your body makes too many red blood cells, which causes your blood to thicken.
  • Myelodysplastic syndromes: A group of diseases characterized by your bone marrow not producing enough healthy blood cells (anemia).

What are common symptoms of bone marrow conditions?

Common symptoms of bone marrow conditions include:

What are common tests to check the health of my bone marrow?

There are two tests to check the health of your bone marrow and/or blood cells:

  • Bone marrow aspiration: A needle removes fluid and cells from your bone marrow (bone marrow concentrate). The aspirate test identifies what cells are present in your bone marrow, verifies whether or not those cells are normal or abnormal and gives other information about the characteristics of your cells.
  • Bone marrow biopsy: A large needle removes a piece of your bone marrow. The biopsy shows where, how many and the types of cells are present in your bone marrow.

Is it painful to remove my bone marrow?

For a bone marrow test or donation, you’ll receive an anesthetic, so you won't feel any pain during the procedure. After the procedure, you may feel side effects, which include aches and pain at the site of the incision. Each individual experiences pain differently, so the severity could vary from person to person. The pain may last for a few days or up to several weeks.

What are common treatments for bone marrow conditions?

Treatments for bone marrow conditions vary based on the severity and progress of the diagnosis. Treatment options include:


How do I keep my bone marrow healthy?

Bone marrow is the foundation of your bones, blood and muscles. Keeping your bone marrow healthy focuses on supporting components of your body that grow from bone marrow cells. You can keep your bone marrow healthy by:

  • Eating a diet rich in protein (lean meats, fish, beans, nuts, milk, eggs).
  • Taking vitamins (iron, B9, B12).
  • Treating medical conditions where bone marrow abnormalities are a side effect.

A note from Cleveland Clinic

Bone marrow is the soft center of the bones in your body. Bone marrow is necessary to create components of your blood and store fat. The best way to keep your bone marrow healthy is to support the parts of your body that your bone marrow produces, like your blood, muscles and bones.

Medically Reviewed

Last reviewed by a Cleveland Clinic medical professional on 04/21/2022.

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