While you sleep, the muscles of your throat relax, your tongue falls backward, and your throat becomes narrow and “floppy.” As you breathe, the walls of the throat begin to vibrate – generally when you breathe in, but also, to a lesser extent, when you breathe out. These vibrations lead to the characteristic sound of snoring. The narrower your airway becomes, the greater the vibration and the louder your snoring. Sometimes the walls of the throat collapse completely so that it is completely occluded, creating a condition called apnea (cessation of breathing). This is a serious condition which requires medical attention.
There are several factors which facilitate snoring. First, the normal aging process leads to the relaxation of the throat muscles, thus resulting in snoring. Anatomical abnormalities of the nose and throat, such as enlarged tonsils or adenoids, nasal polyps, or deviated nasal septum cause exaggerated narrowing of the throat during sleep and thus lead to snoring. Functional abnormalities (e.g. inflammation of the nose and/or throat as may occur during respiratory infection or during allergy season) will result in snoring. Sleep position, such as sleeping on your back, may lead to snoring in some people. Alcohol is a potent muscle relaxant and its ingestion in the evening will cause snoring. Muscle relaxants taken in the evening may lead to or worsen snoring in some individuals. One of the most important risk factors is obesity, and in particular having a lot of fatty tissue around the neck.