Today’s Wonder of the Day was inspired by Katherine. Katherine Wonders, “How does your brain tell you what you like to eat?” Thanks for WONDERing with us, Katherine!
Just the other day we were walking past the Wonderopolis gardens when we overheard an interesting conversation between a couple of rabbits:
Rabbit 1: Hey Roger! What's up with all these carrots?
Rabbit 2: I don't know, Eddie. I like to hang out here a lot. Every time the humans see me, they throw carrots at me.
Rabbit 1: Eww! Why do they do that? I hate carrots!
Rabbit 2: Me, too! They bring sandwiches, hot dogs, cookies, and chips on picnics, but do they ever share any of that food? No way! I'd do a backflip for a cheeseburger right now.
Rabbit 1: Mmm…a cheeseburger does sound good right now. Want to go to Old MacDonald's for lunch?
Rabbit 2: Let's do it! Maybe we can trade all these carrots for some French fries!
We were puzzled by the rabbits' conversation, since we had always assumed that all rabbits loved carrots. In fact, their conversation made us start WONDERing about the foods we eat. Why don't we all like the same foods?
If you've ever been out to eat at a restaurant with your family, you've probably noticed that everyone doesn't usually order the same meal. In fact, if there are five people at your table, there are probably five different meals ordered.
Some foods, such as ice cream and pizza, seem to appeal to most, if not all, people. Other foods, like broccoli and spinach, seem to be an acquired taste that relatively few people have acquired. What drives these differences in our tastes?
Scientists who have studied foods and our sense of taste have identified a variety of factors that lead to our likes and dislikes when it comes to foods. First, we're not all created equally when it comes to taste buds. The number of bumps on our tongues (called papillae) that contain taste buds varies from one person to the next.
People with many papillae are known as "supertasters." They can find flavors overwhelming and often prefer foods that are mild rather than spicy. Those who have a low papillae density are called "subtasters," and they're the people who tend to like spicy food and hot sauce on everything.
Our sense of taste depends upon more than just the number of taste buds, though. It also depends upon our taste buds' ability to detect the wide variety of chemicals that can trigger the signals that help our brains interpret the five different tastes: sweet, sour, salty, bitter, and savory.
Scientists believe our sense of taste definitely has a genetic component. For example, researchers have identified a range of 20-40 genes they believe influence how our brains and taste buds sense bitter tastes.
Humans appear to be born with a natural love of sweet flavors and an aversion to bitter and sour flavors. Scientists believe these genetic predispositions have evolutionary roots, since sweet flavors would likely come from good food sources, such as fruits, while bitter and sour flavors would often come from dangerous plants that should be avoided.
Experience also plays a role as we grow up. For example, babies often tend to like foods their mothers ate before they were born. Children exposed to a wide variety of foods when young also tend to like more foods than those fed a limited diet.
Gender and culture can also play roles in our tastes. Women tend to crave sweets, while men often prefer salty foods. Bitter or spicy foods may be more popular if you're part of a culture that celebrates those foods and eats them regularly.
Finally, scientists also know that texture plays a big role in many people's likes and dislikes. They can't really explain why yet, but it's clear that some people simply don't like certain textures — slimy, chewy, gritty, creamy, or stringy — regardless of flavor.