Why do people snore?

Air passage (airway) showing muscles causing snoring

Diagram of mouth showing uvula, tonsil and soft palate

Snoring gets louder when snorer lies on their back

Many snorers snore louder when they lie on their backs. Even people who don't usually snore are more likely to snore when sleeping on their backs. That is because when people lie facing upward, gravity encourages throat tissues to sag more than in other positions. The airway becomes more narrow and muscles sag more. As the airway becomes more narrow, the turbulence gets stronger. The stronger the turbulence, the louder the snore.

In short:

• The more muscles sag, the narrower the airway passage.
• The narrower the airway passage, the stronger the turbulence of the throat.
• The stronger the turbulence, the louder the snore.