Taste Thresholds for Bitterness and Cigarette Smoking

A SIGNIFICANT correlation has been reported between taste sensitivity for bitter-tasting compounds such as quinine and number of reported foods disliked¹. Cigarette smoking has also been observed to be associated with the bitter taste threshold variable^2,3. No associations were observed, however, between taste thresholds for hydrochloric acid, sodium chloride, acetic acid and sucrose, on the one hand, and number of foods disliked¹ or cigarettes smoked^2,3 on the other. This communication records the association between the smoking habits of 31-50-year-old males and females, and their taste thresholds for two bitter-tasting compounds, quinine and 6-n-propylthio-uracil (PROP). The latter is a phenylthiourea (PTC) type compound, taste sensitivity to which is bimodally distributed, consistent with the hypothesis of a simple genetic dichotomy^4-6. The `heavy cigarette smokers' smoke 20 or more cigarettes a day, and we compared their thresholds for quinine and PROP with those of non-smokers.