Have you ever smelled something that wasn't there? We've probably all had that experience once, but what if this happened to you all the time? And worse, what if the odor was a nasty one, like an ash tray filled with cigarette butts or burning hair?
It's more common than you might think. A study published on Aug. 16, 2018 in the journal JAMA Otolaryngology-Head and Neck Surgeryfound that one in 15 Americans over the age of 40 experienced phantosmia or phantom odor perception, the phenomenon of smelling odors that aren't really there. This study is the first in the U.S. to use national data to determine how widespread this condition really is.
The National Institute on Deafness and Other Communication Disorders, which is part of the U.S. National Institutes of Health, looked at data collected by the National Center for Health Statistics from 2011 to 2014 from 7,417 participants, all over age 40. Participants were asked if they sometimes smelled unpleasant, bad or burning odors when no cause is present.
The results showed that 6.5 percent of participants experience phantom odors, with a higher prevalence among younger age groups, women and people of lower socioeconomic status. Commonly reported phantom odors include the smell of burning rubber, chemicals and spoiled or rotten food. In addition, "Phantom odor perception was more common among those with poorer health, a history of head injury, or dry mouth symptoms," the researchers wrote in the study. Alcohol and tobacco exposure also appear to play a role.
The health-related issues could signal a possible connection, because medications used to treat generally poor health and persistent dry mouth could be a contributing factor. The authors also noted that the incidence of phantom odor perception could be lowered by preventing head injuries. Far more research is necessary, however, before definitive recommendations can be made.
Donald Leopold, M.D., one of the study authors and a clinical professor in the Department of Surgery at University of Vermont Medical Center, Burlington, notes in a press statement that people who experience strong phantom odors sometimes have a poor quality of life and trouble maintaining a healthy weight.
"The causes of phantom odor perception are not understood. The condition could be related to overactive odor sensing cells in the nasal cavity or perhaps a malfunction in the part of the brain that understands odor signals," explains lead researcher Dr. Kathleen Bainbridge in a press release. "A good first step in understanding any medical condition is a clear description of the phenomenon. From there, other researchers may form ideas about where to look further for possible causes and ultimately for ways to prevent or treat the condition."