Supertaster

In 1931, Arthur L. Fox, a DuPont chemist, discovered that some people found phenylthiocarbamide (PTC) to be bitter while others found it tasteless.[3][4] At the 1931 American Association for the Advancement of Science meeting, Fox collaborated with Albert F. Blakeslee, a geneticist, to have attendees taste PTC: 65% found it bitter, 28% found it tasteless, and 6% described other taste qualities. Subsequent work revealed that the ability to taste PTC is genetic.

In the 1960s, Roland Fischer was the first to link the ability to taste PTC, and the related compound propylthiouracil (PROP), to food preference, diets, and calorie intake. Today, PROP has replaced PTC for research because of a faint sulfurous odor and safety concerns with PTC.[5] Bartoshuk and colleagues discovered that the taster group could be further divided into medium tasters and supertasters.[6] Research suggests 25% of the population are non-tasters,[7] 50% are medium tasters, and 25% are supertasters.[8]

The bitter-taste-receptor gene TAS2R38 has been associated with the ability to taste PROP[12] and PTC,[13] although a causal relationship with the supertaster phenomenon has not been established.[14] Additionally, the T2R38 genotype has been linked to a preference for sweetness in children,[15] avoidance of alcoholic beverages,[12] increased prevalence of colon cancer (because of inadequate vegetable consumption),[16] and avoidance of cigarette smoking.[17]

Women are more likely to be supertasters, as are those from Asia, South America, and Africa.[7] Female supertasters tend to have a lower body mass index and better cardiovascular health. This could be because supertasters may not have a high predilection for sweet or high-fat foods compared to the average person.[18]

The tongue's fungiform papillae can be revealed with blue food dye.

Supertasters were initially identified based on the perceived intensity of propylthiouracil (PROP) compared to a reference salt solution. Supertasters consume more salt in comparison to those with average taste.[19] Because supertasters have a more sensitive sense of taste than medium or non-tasters, this can cause Image scaling artifacts.[4] Subsequently, salt has been replaced with a non-oral gustatory standard. Therefore, if two individuals rate the same gustatory stimulus at a comparable perceptual intensity, but one gives a rating twice as large for the bitterness of a PROP solution, the experimenter can be confident the difference is real and not merely the result of how the person is using the scale. Today, a phenylthiocarbamide (PTC) test strip is used to help determine if someone is a low taster. The general population tastes this as bitter about 75% of the time.[20]

Many studies do not include a cross-modal reference and categorize individuals based on the bitterness of a concentrated PROP solution[21][22] or PROP-impregnated paper.[23] Supertasters tend to have more fungiform papillae and pain receptors than tasters and non-tasters.[24] It is also possible to make a reasonably accurate self-diagnosis at home by carefully examining the tongue and looking for the number of fungiform papillae.[25]