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Why do we get tired after eating?

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Answer: Hormones and brain chemicals shift

Hormones and brain chemicals shift ✓ — Correct! After eating, your body releases insulin to process glucose. This triggers tryptophan to enter the brain, where it converts to serotonin and melatonin - chemicals that promote sleep. Orexin levels also drop. Large meals, especially with carbs, amplify this effect. This is why you feel drowsy after lunch, often called a 'food coma'.

Body temperature rises — Wrong. Body temperature does rise slightly during digestion, but post-meal drowsiness is caused by hormonal changes - particularly increased serotonin and melatonin production after insulin release.

Too much oxygen used — Wrong. Oxygen use doesn't cause post-meal fatigue. Sleepiness comes from hormonal shifts - insulin triggers tryptophan conversion to serotonin and melatonin in the brain.

Go deeper: Insulin · Tryptophan · Orexin
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