Is Fast Food Killing Our Sense of Taste?
Your sense of taste is being barraged by the loads of salt, fat, and sugar found in double cheeseburgers, waffle fries, and milkshakes.
Did you ever notice that all fast food joints have the same "smell"?
Hot oil mixed with eau de onion? Some people have even half-jokingly suggested
there may be a secret addictive chemical pumped in.
"[The sense of taste] is in a bad way," Steven A. Witherly, PhD,
president and CEO of Technical Products Inc., a food consulting firm in
Valencia, Calif., tells WebMD. "Fast food has ridiculously high levels of
salt, fat, and sugar -- and the brain likes salt, fat, and sugar."
Everyone has about 10,000 taste buds on his or her tongue (although these
may thin as people grow older). "Fast food does not so much dull the taste
buds as affect how the brain processes that taste as pleasurable or
unpleasant," Witherly says. Hormones such as insulin and leptin also affect
the brain's impression of a given food. "Snack food is affecting how we
Sense of Taste Deceptively Simple
Traditionally, scientists have said the sense of taste can detect salty,
bitter, sour, and sweet. Now, Witherly says, a fifth taste found to be directly
received by the tongue is umami (pronounced "ooo-mommy"), which is the
monosodium glutamate (MSG) taste. Parmesan cheese is huge on this, 1% by
weight; soy sauce is also 1%. Umami is tied to a protein found in breast milk
that the brain is attracted to.
Witherly also says the human sense of taste can recognize the hot pepper
taste and another he calls the fatty acid taste.
Marcia Levin Pelchat, PhD, a psychologist and research scientist with the
Monell Chemical Senses Center in Philadelphia, tells WebMD the hot pepper taste
is more of a skin irritation signal in the inner cheek rather than a taste.
(Carbonation, she says, provides a similar irritation that can be studied by
Whatever triggers them, your sense of taste picks up the signal and sends it
to the brain for interpretation and combination with other tastes.
Certain sensations -- like salt, sugar, and to some extent, the sensation of
fat -- become an expectation. People want to experience them. "I have seen
people's brain scans light up in the pleasure centers when fat passes over
their tongue," Witherly says.
In fact, researchers at Yale University, led by Linda A. Bartoshuk, PhD,
have discovered that about 35% of white women and 15% of white men are
"supertasters," people with an exaggerated sense of taste, compared
with the rest of us mortals. These souls inhabit a more limited food universe
because their sense of taste is so much more intense. For one thing, they tend
to eat fewer bitter vegetables, the kinds that are thought to ward off cancer.
On the good side, supertasters also spurn fatty foods more often and thus
develop less heart disease.
"Fast food," Bartoshuk tells WebMD, "does not physically affect
taste buds, but it may affect appetite and food preferences."