What Does the Uvula Do?

Given how frequently doctors look in peoples' mouths, physicians probably get asked this question a dozen times a day by curious patients.  This question of uvular function also extended into ancient times with a variety of theories proposed over the years...

Hippocrates and Aristotle in the 4th century B.C. and Berenargio da Carpri in 1900 referred to the uvula only as a source of possible inflammation and edema capable of causing suffocation.

Galen (122-199 A.D.) considered it to be an important structure contributing to human voice production.

Delavan (1923) felt that the uvula acted as a drain for mucous secretion from the nose by directing flow towards the base of the tongue where it is expelled.

Ewens (1934) suggested that the uvula is a vestigial remnant.

Richardson and Pullen (1948) suggested that the uvula provided only a functional role protecting the orifices of the eustachian tubes (tunnel that goes up into the ear).

Kaplan (1971) felt the uvula prevented excessive nasality of the voice by controlling resonance of the air column over the larynx.

Palmaris (1972) stated that the uvula served no important function.

Langdon and Klueber (1978) suggested that the uvula facilitates glandular secretion.

Israel researchers (1988) suggested that the uvula provides an important function in drinking and swallowing.

The same researchers later revised their opinion in 1992 after discovering that most lower animals they looked at do not have a uvula. (Animals they checked included sheep, calves, foals, dogs, cats, pigs, Macaca Mulata, baboons, and chimpanzees.) Histologically, they also found an unusually large amount of serous glands within the human uvular musculature. Based on the absence of an uvula in animals in combination with the high serous gland content in the human uvula, they hypothesize that the human uvula's main role is in preventing excessive throat drying during speech.

Today, it is felt that although the uvula may provide some lubricating function, removal does not seem to cause any significant deficits. In fact, removal may help improve a patient's well-being by potentially eliminating snoring as well as resolving other sleep related problems.

Just as an FYI... The Bedouin believe that uvula removal increases their ability to tolerate thirst.  In fact, uvula removal is a common practice in folk medicine or as a ritual act to this day documented in the Middle East, North Africa, the Arabian peninsula, and among some Bedouin tribes in southern Sinai.



References:
The riddle of the uvula. Otolaryngol Head Neck Surg. 1992 Sep;107(3):444-50.

The velopharyngeal muscles in speech. Acta Otolaryngeal 1969;Suppl 250:1-77.

Readaptation of the velopharyngeal valve following uvulopalatopharyngoplasty. Plast Reconstr Surg 1988;82:20-7.

Why do we have a uvula?: literature review and a new theory. Clin Otolaryngol Allied Sci. 2004 Dec;29(6):689-93.

Resection of uvula in native medicine of Arabia, Kordofan, and Ethiopia. Rev Med Trop 1940;1:288-93.