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Severity of Onion Tearing and Chemosensory Sensitivity: A Preliminary Investigation
Mehmet K Mahmut1,2, Rachel S Herz3, Anabel Bormann1
1Interdisciplinary Clinic of Smell and Taste, Department of Otorhinolaryngology Technische Universität Dresden Dresden Germany.
Objectives:
Involuntary tearing is an annoyingly common consequence of cutting onions. Little is known about who experiences so-called "onion tears" and to what extent they experience them. Our aim with this study was to explore whether the degree of onion tearing is a phenotypic predictor of olfactory function and trigeminal sensitivity, assessed by both self-report and psychophysical measures of chemosensory function.
Methods:
A total of 1001 participants (598 females; M age 44 years) completed four subjective ratings of nasal function (subjective smelling ability, nasal sensitivity, trigeminal sensitivity, and nasal patency), three psychophysical tests (odor identification, AmmoLa intensity, and odor lateralization), and answered questions about the severity of their tearing while cutting onions.
Results:
Results revealed that higher levels of onion tearing were associated with better self-rated olfactory ability, nasal breathing, and higher sensitivity to nasal stinging/burning. No statistically significant relationship was found between the psychophysical tests of olfactory ability and degree of onion tearing. Performance on all measures was also analyzed across three different age brackets (18-35; 36-55; 56+ years) and yielded mixed findings related to subjective ratings of trigeminal sensitivity and olfactory function.
Conclusion:
Clinically, there is yet to be a universally accepted measure to determine subjective chemosensory sensitivity, and in particular, trigeminal sensitivity. Despite inconsistencies between the subjective and objective chemosensory tests, our findings suggest that asking someone about the severity of their tearing while cutting onions may be a useful addition to standard testing assessing chemosensory and trigeminal sensitivity.
Level Of Evidence:
3.
Insights
Experiencing more tears when cutting onions may indicate better self-reported smell and nasal sensitivity. This simple observation could aid in assessing chemosensory and trigeminal sensitivity.
Area of Science:
- Otorhinolaryngology
- Chemosensation Research
- Sensory Science
Background:
- Involuntary tearing from onions is common, but individual differences and their relation to sensory perception are not well understood.
- Assessing olfactory and trigeminal sensitivity often relies on subjective reports and objective tests, with a need for more accessible measures.
Purpose of the Study:
- To investigate if the degree of "onion tears" correlates with olfactory function and trigeminal sensitivity.
- To determine if onion tearing severity can serve as a phenotypic predictor for chemosensory abilities.
Main Methods:
- 1001 participants provided subjective ratings of nasal function and completed psychophysical tests for olfaction.
- Participants also reported the severity of tearing experienced when cutting onions.
Main Results:
- Higher onion tearing correlated with better self-rated olfactory ability, nasal breathing, and trigeminal sensitivity (stinging/burning).
- No significant link was found between onion tearing severity and objective olfactory test performance.
- Age-related analysis showed mixed results for subjective trigeminal and olfactory ratings.
Conclusions:
- Self-reported onion tearing severity may offer a simple, supplementary method for assessing subjective chemosensory and trigeminal sensitivity.
- This finding could be valuable in clinical settings where standardized measures for trigeminal sensitivity are lacking.
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