Depending on what time it is, your body responds differently to an injury or infection. During the day, you're likely to heal faster and fight infection better than at night.
Historically, scientists weren't entirely sure why.
That picture is starting to clear up thanks to a new study published last week in the journal Science Immunology. The research finds a missing piece of the puzzle in neutrophils, powerful immune cells that — despite living less than 24 hours — know the difference between day and night.
Got a question about how the body works? Let us know at shortwave@npr.org.
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This episode was produced by Berly McCoy and Jordan-Marie Smith, edited by Rebecca Ramirez and Christopher Intagliata and fact checked by Tyler Jones. Tiffany Vera Castro and Jimmy Keeley were the audio engineers.
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