Effects of capsaicin and menthol on oral thermal sensory thresholds.
OBJECTIVE
To determine the long-term effect of capsaicin and short-term effect of menthol on oral thermal thresholds.


METHODS
The thresholds for cold detection (CDT), warm detection (WDT), cold pain (CPT) and warm pain (WPT) were determined in 11 regular chilli-eaters (capsaicin group) and 11 control subjects that were closely matched for age, gender and ethnicity. The effect of menthol was determined by asking all 22 participants to suck a lozenge containing 0.52% menthol for 5min.


RESULTS
An ANOVA revealed a significant difference between the capsaicin and control groups (P=0.014), with the greatest difference in the WDT (capsaicin group 4.7+/-2.7[S.D.] degrees C; control group 2.3+/-2.2 degrees C). Immediately after sucking a menthol lozenge there was a significant rise in the CDT (2.2+/-1.1 degrees C to 5.9+/-6.2 degrees C; P<0.01) and WDT (3.6+/-2.7 degrees C to 7.6+/-4.4 degrees C; P<0.001).


CONCLUSIONS
The consumption of foods containing capsaicin and menthol significantly alters thermal sensory thresholds in the oral cavity. Dietary habits should therefore be taken into account when intra-oral thermal thresholds are determined.
Kalantzis
A
A
University of Sheffield, Claremont Crescent, UK.
Robinson
P P
PP
Loescher
A R
AR
D000328:Adult; D000704:Analysis of Variance; D002211:Capsaicin / Q000494:pharmacology*; D016022:Case-Control Studies; D004347:Drug Interactions; D005260:Female; D006801:Humans; D008610:Menthol / Q000494:pharmacology*; D009055:Mouth / Q000187:drug effects*; D009412:Nerve Fibers / Q000187:drug effects*; D010465:Perception; D012684:Sensory Thresholds / Q000187:drug effects*; D013268:Stimulation, Chemical; D013697:Thermosensing / Q000187:drug effects*; D013997:Time Factors
D008610:Menthol; D002211:Capsaicin