We bleed because our skin, the body's protective layer, is damaged, rupturing the blood vessels beneath it. This allows blood to escape from the circulatory system.
Understanding Bleeding
Bleeding, or hemorrhage, is the loss of blood from the circulatory system. The severity of bleeding depends on the extent of the damage to the blood vessels. A minor cut might only break small vessels near the skin's surface, resulting in minimal blood loss. More significant injuries, however, can damage larger vessels and cause substantial bleeding.
Types of Bleeding
- Minor cuts and abrasions: These typically involve small blood vessels and result in minimal bleeding, easily stopped with pressure.
- Deep cuts and amputations: These sever larger blood vessels, leading to significant blood loss requiring immediate medical attention.
- Internal bleeding: This occurs when blood vessels are damaged inside the body, potentially leading to serious complications if left untreated. Examples include nosebleeds (epistaxis) and rectal bleeding.
- Note that women with a uterus experience both normal and abnormal bleeding related to menstruation and other physiological processes.
Why We Bleed – The Mechanism
As stated in multiple sources (Yahoo News, Jan 31, 2022 article and October 14, 2023 article), the skin serves as a protective barrier. When this barrier is compromised, the underlying blood vessels are damaged, causing bleeding. The amount of bleeding depends on the size and type of vessels injured. Even minor injuries damage small capillaries, arterioles, and venules, resulting in visible bleeding (Quora). Applying pressure directly to a wound helps to constrict the blood vessels, slowing blood flow and aiding in clotting (The Conversation).
The Body's Response to Bleeding
The body has natural mechanisms to stop bleeding, including blood clotting and vasoconstriction (narrowing of blood vessels). However, severe injuries may overwhelm these mechanisms, requiring medical intervention.
