Which type of bones contains the most bone marrow in the human body?

Flat bones contain the most bone marrow in the human body because they have a larger surface area relative to their volume and are typically composed of two layers of compact bone surrounding a layer of spongy bone, which houses a significant amount of red marrow. This red marrow is primarily responsible for hematopoiesis, the production of blood cells.

In particular, flat bones such as the skull, pelvis, and sternum are rich in red bone marrow, making them critical sites for blood cell production throughout a person's life. While long bones also contain marrow, particularly in their medullary cavities, the overall volume of marrow is generally less compared to the extensive area found in flat bones. Irregular and short bones do also contain marrow, but they do not offer the same abundance or surface area dedicated to this function as flat bones do. Therefore, flat bones are recognized as the main contributors to bone marrow in the body.