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What is serotonin?

Medicine & HealthLesson on requestFree to read

Quick answer

Serotonin is a chemical messenger (neurotransmitter) that helps regulate mood, sleep, appetite, and digestion. Often called a 'feel-good' chemical, it helps stabilize mood and is a major target of many antidepressant medications. It carries signals between nerve cells in the brain and also acts widely in the gut.

Key things to understand

  1. It carries signals between nerve cells in the brain and also acts widely in the gut.
  2. It influences mood, sleep, appetite, memory, and even blood clotting.
  3. Most of the body's serotonin is actually made in the digestive tract, not the brain.
  4. Many antidepressants (SSRIs) work by keeping more serotonin available between neurons.
  5. It is a precursor to melatonin, the hormone that helps control your sleep cycle.

People also ask

Does serotonin make you happy?
It helps stabilize and lift mood, but happiness involves many chemicals and circumstances — serotonin is one important piece, not a simple 'happiness switch'.
How do SSRIs use serotonin?
SSRIs (selective serotonin reuptake inhibitors) slow how fast neurons reabsorb serotonin, leaving more available to ease symptoms of depression and anxiety.
How is serotonin linked to the gut?
Around 90% of the body's serotonin is produced in the gut, where it helps control digestion — part of the close 'gut-brain' connection.