Why do I always feel tired after lunch? © iStock

Why do I always feel tired after lunch?

There might be an evolutionary explanation for your afternoon snooze.

Asked by: Anonymous


A full stomach diverts blood to the vessels in the abdomen, to help supply oxygen to the digestive organs and transport absorbed nutrients away. This reduces blood flow to the brain and makes you feel sleepy.

It’s possible that this also represents an adaptation to discourage strenuous activity after a big meal. A heavy meal makes you a slower runner and sleeping it off on the prehistoric sofa was probably a safer strategy for our ancestors.


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