What Does the Spleen Do? A Guide to Spleen Function
Summary
The spleen is a vital organ located beneath the diaphragm that serves as the body’s primary blood recycling system. It filters and removes damaged or old red blood cells while also acting as a blood reserve and supporting immune function. Understanding its role highlights why maintaining spleen health is important for overall wellbeing.
Key Takeaways
- The spleen is located underneath the right ribcage, beneath the diaphragm, and measures approximately 2.8–5.5 inches (7–14 centimeters)
- Its primary function is acting as a recycling plant for blood — breaking down old, damaged, and misshapen red blood cells
- The spleen recovers and recycles iron from old red blood cells, converting them into reusable amino acids
- Without this recycling process, damaged red blood cells could accumulate and cause vascular damage or blockages
- The spleen serves as a blood reserve, holding approximately one cup of blood available for emergency use
- The spleen plays a meaningful role in immune system function, helping defend the body against infections
- People who have their spleen removed experience increased susceptibility to infections, underscoring its immune importance
Details
Anatomy and Location
The spleen sits on the left side of the body (the transcript references the right ribcage, though anatomically it resides on the upper left), tucked beneath the diaphragm. It is a relatively small organ, ranging from 7 to 14 centimeters in length.
The Recycling Function
The spleen’s core job is filtering the bloodstream for red blood cells that are:
- Old and worn out
- Misshapen or malformed
- Damaged
These compromised cells are broken down and their components — particularly iron — are extracted and recycled. The remaining material is converted into amino acids, which the body can then reuse. This continuous filtration prevents damaged cells from accumulating in the vascular system, where they could cause blockages or tissue damage.
Blood Reserve
Beyond filtration, the spleen functions as an emergency blood storage unit, holding roughly one cup of blood. This reserve can be released into circulation when the body requires additional blood volume, such as during physical stress or blood loss.
Immune System Support
The spleen also contributes to immune function, though the transcript does not detail the specific mechanisms involved. The practical implication is clear: individuals who have undergone a splenectomy (surgical removal of the spleen) face a measurably higher risk of infection. This makes maintaining general health particularly critical for those living without a spleen.