You probably already know that your taste buds have something to do with your food preferences, but you'll likely be surprised to learn how deeply those preferences are rooted in your body's survival instincts. We spoke to the experts to learn more about taste buds, and uncovered loads of surprising information, from how pregnancy can affect taste to why some people have more sensitive palates. Read on to learn seven surprising facts about taste buds.
1. You can't see your taste buds.
Those bumps you see on your tongue when you say "ahh"? They aren't taste buds. "Those round projections are called fungiform papillae and each has an average of six taste buds buried inside its surface tissue," says Linda Bartoshuk, PhD, director of human research at the University of Florida Center for Smell and Taste. Specialized taste receptors inside the taste buds allow us to distinguish sweet, salty, sour and bitter—and a possible fifth taste called umami, which has a savory element––by sending a message to the brain. And you don't just have taste buds on your tongue—they're everywhere, from the roof of your mouth to your throat and stomach.
2. Not everyone has the same amount of taste buds.
According to Nicholas Bower, MD, district medical director at MedExpress, the average adult has between 2,000 and 10,000 taste buds. People who have more than 10,000 are considered to be "supertasters" because they taste things more intensely. "Research has shown that supertasters don't like vegetables very much because they taste bitterness so intensely," says Dr. Bartoshuk. "They also may find very sweet desserts, like crème brûlée, to be over-the-top sugary." To find out where you fall on the taste spectrum, Dr. Bartoshuk recommends an easy at-home test: Apply a couple of drops of blue food color to your tongue and swallow a few times. Then examine your tongue's surface; fungiform papillae won't pick up the dye, so they'll look like pink polka dots on a blue background. If your tongue appears to be almost solid pink, then you have tons of fungiform papillae and may be a supertaster.
3. Taste and flavor are not the same thing.
Taste is what your taste buds pick up: sweet, salty, sour, bitter and potentially umami (the fifth savory taste). Flavor is a combination of taste plus smell, specifically "retronasal olfaction," which is how your brain registers scent when you eat something. For example, sniffing a chocolate doughnut will send a scent message through your nostrils to one part of your brain, and eating it will send a different type of scent signal to a different part of your brain. It is the scent message from eating that combines with taste to create flavor. However, according to Dr. Bartoshuk, the scent message from smelling with your nose is not involved with flavor at all (your brain knows the difference between the two).
4. Taste buds are designed to keep us alive.
"The purpose of our ability to distinguish tastes is survival," says Trey Wilson, DDS, a New York City–based dentist. "Taste buds tell your brain whether or not to swallow what's already in your mouth." According to Dr. Bartoshuk, infants are born loving sweet and hating bitter, because natural sugar—not the sugar in, say, a processed candy bar, as we think of it today—is brain fuel, while bitter is the sensory cue for poison. "The taste system evolved to protect a baby who hasn't learned anything about what is good and bad for himself yet," she explains. Additionally, sodium is a mineral that's essential for making our muscles and nerves work, thus many people's cravings for salty snacks.
5. Your flavor preferences aren't set in stone.
You can train your palate to enjoy new foods—just ask any adventurous eater who used to be a picky toddler. "By our watching our parents and friends, our brain learns what foods are 'good,'" says Dr. Bower. Want to expand your child's—or your own—palate? According to Dr. Bartoshuk, bringing out the sweetness of something will make it more palatable, as will adding something fatty, since your stomach has fatty acid receptors, which send a pleasing signal to your brain. So pairing broccoli with cheese, or roasting it to pull out its natural sugars, will likely make it more enjoyable. "Or you could add social cues: Eat it with someone else who really enjoys it, or with someone whom you admire and like. All of these things can make the food seem more appealing." Similarly, if you eat something you used to love right before getting hit with the stomach flu, chances are you'll have an aversion to that food for quite some time.
6. Our taste preferences may fluctuate with our hormones.
Have you ever noticed that many pregnant women in their first trimester can't stand the sight of vegetables? Their taste buds may be protecting them against potential harm. "I suspect that because the taste of bitter is hardwired to be a cue for poison, early in pregnancy your brain becomes sensitized to avoid it in order to guard your baby," says Dr. Bartoshuk. Similarly, pregnant women crave foods that tend to be high energy sources—something women need more of during pregnancy––like sugars and carbohydrates in the form of bread, candy or other sweets. As for the classic pregnancy cravings of ice cream and pickles, according to Dr. Bartoshuk, they most likely have very little to do with what a woman's body needs. While craving ice cream could be a hankering for an energy source, pickles aren't a source of anything that a pregnant woman might need.
7. Taste buds are constantly regenerating.
Taste buds go through a life cycle where they grow from basal cells into taste cells and then die and are sloughed away. According to Dr. Bartoshuk, their normal life cycle is anywhere from 10 days to two weeks. However, "burning your tongue on hot foods can also kill taste buds," she says. "But they grow right back, which is why the ability to taste doesn't diminish with age." Though Dr. Bartoshuk notes that taste remains robust as we get older, the ability to taste bitterness does decline in women with the onset of menopause. Since, on a primal level, the ability to taste bitter may protect a pregnant woman's baby, those receptors may stop working after a woman's childbearing years are over because it is no longer a reproductive necessity.