# what causes swelling?

**URL:** <https://boards.straightdope.com/t/what-causes-swelling/152105>\
**Category:** Factual Questions\
**Created:** [February 1, 2003, 3:25pm UTC](https://boards.straightdope.com/t/what-causes-swelling/152105 "2003-02-01T15:25:54Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![regnad\_kcin](https://avatars.discourse-cdn.com/v4/letter/r/85f322/32.png) [@regnad\_kcin](https://boards.straightdope.com/u/regnad_kcin)\
**Post date:** [February 1, 2003, 3:25pm UTC](https://boards.straightdope.com/t/what-causes-swelling/152105/1 "2003-02-01T15:25:54Z")

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What causes a body part to swell when there is an injury or an infection?

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**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\
**Post date:** [February 1, 2003, 5:15pm UTC](https://boards.straightdope.com/t/what-causes-swelling/152105/2 "2003-02-01T17:15:08Z")

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A complex biological mechanism, which begins with the release of chemicals at the site of injury. This attracts white blood cells to the area, makes the local circulatory system a bit leaky, and that results in fluids and cells leaking outside into the tissue to fight infection and repair damage.

A very simplistic summary, and as a result not perfectly correct, but good for basic enlightenment purposes.

QtM, MD