It has been suggested that part of the widespread preference for chih pepper can be explained as a desensitization of the chemical irritant receptors in the mouth, produced by continued exposure to chili pepper. To evaluate this possibility, we measure detection thresholds and salivary response of subjects who vary in liking for chili pepper and amount of exposure to it. The stimuli used are aqueous solutions of capsaicin, the purified piquant agent in chili peppers. We find very small but reliable and significant decreases in sensitivity to capsaicin for both measures by chili likers or users. We conclude that there is a slight desensitization effect, but also that it cannot be a major factor in explaining the acquisition of chili preference. There is too much overlap between groups, and chili likers claim to like chili because of its chemical irritant (“mouth burn”) effect, not in spite of it.