Ask A Scientist
What causes one to hic-cup and why doesn't it stop easily?
Asked by: Scott Frazier
School: Sidney high School
Teacher: David Pysnik
Hobbies/Interests: Playing Sports, Talking with friends
Career Interest: N/A
Answer from Leann Lesperance
Research assistant professor, Binghamton Universit
Ph.D. School: MIT
MD School: Harvard
Research area: Type 2 Diabetes; Health care quality.
Family: Husband, Drew Deskur, daughters Teresa (4) and Catherine (2)
Interests/hobbies: Singing, nutrition/fitness, gardening, travel
Hiccups, those funny noises that we make from time to time, are caused by a sudden movement of the diaphragm, the muscle that controls our breathing. Most of the time, this muscle works as expected, contracting (pulling down toward our belly) smoothly to pull air into the lungs, and then relaxing slowly to let air flow out of our lungs. However, the diaphragm sometimes contracts suddenly. As air starts to rush in, the vocal cords snap shut, causing a "hiccup" sound. While the exact reason for this is not known, one theory suggests that hiccups are left over from some "primitive" reflex. Interestingly, babies in the womb hiccup even before they make any breathing movements. Often there is no obvious cause for hiccups. In some cases, hiccups are caused by irritation of one of the nerves that run from the brain down to the diaphragm. For example, this can happen when a person eats too fast, or eats or drinks too much. It can also happen with certain illnesses such as sore throat, acid reflux, stomach ulcers, and lung infection (pneumonia). Most hiccups go away on their own after a few minutes, as mysteriously as they started. Nevertheless, many people have favorite tricks for getting rid of hiccups, such as holding their breath, drinking water from the opposite side of a glass, putting sugar on the tongue, biting on a lemon, and being frightened. It is possible that these things work because they also act on some nerve, to interrupt the hiccup reflex. They're fun to try anyway!