Usually, it's great to have heightened senses like 20/20 vision or sharp hearing. But a heightened sense of taste, no matter how delicious it might sound, is really no joy. Supertasters are people with two or sometimes just one dominant allele for the gene TAS2R28. And although they can perceive more nuanced flavor in food than nontasters, they often find common foods too bitter, sweet or spicy.
In the 1930s, a scientist at DuPont discovered that people had varying degrees of sensitivity to the chemical PTC (phenylthiocarbamide). For some, PTC tasted shockingly bitter, but for the mystified minority, PTC had no taste at all. Due to concerns about PTC's safety, scientists began studying people's reactions to PROP (6-n-propylthiouracil), a synthetic compound used in thyroid medicine. For nontasters, PROP had no flavor; for tasters, it was unpleasant and for supertasters, PROP slapped the tongue with an intense bitterness.
In 1991, Linda Bartoshuk, then of Yale Medical School, coined the name "supertasters" for the people with acute PROP sensitivity and noticed that they had a denser covering of fungiform papillae than nontasters. She linked the number of taste receptor cells to supertaste.
For supertasters, coffee, hoppy beer and vegetables like Brussels sprouts might be too bitter; cake and ice cream might be too rich and chili peppers might be too hot. There are, however, a few advantages of super taste-sensitivity.
Beverly Tepper, a scientist at Rutgers University, discovered that, at least among women in their 40s, supertasters were 20 percent thinner than nontasters. With their heightened sensitivity to sugar and dairy fats, supertasters are less likely to crave junky foods. They actually eat less food overall -- but, unfortunately, they also skimp on leafy vegetables. Tepper saw no correlation between tasting and weight in men [source: Flaherty].
With such stunning links developing between taste and body mass, scientists are eager to study taste receptors as a possible factor in obesity. Yet just as flavor is more than taste, taste is more than a genetic impulse. People's food preferences and eating habits are largely based on what they grew up on and even what their mothers ate while pregnant.
To learn more about taste, cells and other related topics, sample the links on the next page.