[The Science of Taste: How Your Saliva Transforms Your Food Preferences]-[Spit-Take! The Science Of Saliva And Those Bitter Bites]

Wow in the World · B1 · 2018-09-10

📋 Summary

The Biology of Flavor: Can We Train Ourselves to Love Bitter Foods?

In this episode of Wow in the World, hosts Mindy and Guy Raz explore the fascinating biological connection between our saliva and our taste preferences. While many children—and even adults—find the bitter profiles of vegetables like kale, broccoli, and Brussels sprouts unpleasant, recent scientific research suggests that our perception of these flavors is not fixed. Instead, our bodies possess a remarkable ability to adapt, effectively changing the way we "taste" over time.

The Bitter Truth About Taste

Human beings are naturally inclined to favor certain tastes over others. While we have five basic taste categories—salty, sweet, sour, umami, and bitter—bitter is often the most frequently rejected flavor. Mindy notes that bitter foods, despite being packed with vitamins and antioxidants, are rarely someone’s first choice. This biological aversion serves as a survival mechanism, as bitterness in nature can often signal toxicity. However, this evolutionary trait presents a modern challenge: how do we learn to enjoy the healthiest foods if our brains are hardwired to reject them?

Dr. Cordelia Running’s Saliva Experiment

To investigate whether we can biologically alter our taste perception, Dr. Cordelia Running from Purdue University conducted a unique experiment. She recruited 64 participants to consume chocolate milk with a very low sugar content (only 4%) daily for one week. Because the cocoa was essentially unsweetened, it tasted intensely bitter to most participants at the start of the study.

However, the results were striking. By the end of the week, most participants reported that the chocolate milk no longer tasted as bitter as it did on day one. Their physical reaction to the flavor had shifted, suggesting that their bodies had adapted to the stimulus. This led researchers to examine the role of saliva in the tasting process.

The Role of Salivary Proteins

The key to this transformation lies in our spit. Saliva is not merely water; it is a complex fluid containing various proteins that interact with the chemicals in the food we eat. These proteins help us process different flavors, including bitterness.

Dr. Running’s research at the "Spit Lab" (formally the Saliva Perception, Ingestion, and Tongues Laboratory) revealed that as participants repeatedly consumed the bitter cocoa, their saliva glands began to change. Specifically, the body increased the production of certain proteins that act to dampen or dilute the perception of bitterness. Essentially, the body "learned" to make more of these molecules, which physically altered the flavor profile before the food even reached the brain.

From Biological Adaptation to Habit

This scientific discovery explains why people—like the self-proclaimed "Kale Crusader" Guy Raz—can grow to love foods they once detested as children. It is not necessarily a purely psychological shift where we just "convince" ourselves to like a vegetable; rather, it is a physiological change. By consistently exposing our taste buds to bitter foods, we encourage our bodies to produce the proteins necessary to balance those flavors, making them more palatable over time.

In conclusion, the episode highlights a powerful "wow" moment: what we eat can, over time, determine how we taste. Our biology is not static, and through repeated exposure, we have the power to reshape our palate, making healthy, nutrient-dense foods a genuinely enjoyable part of our diet.

🎯Key Sentences

It's going to be a November to remember.

But for now, let's get on with the show.

I just thought you should know it tastes really terrible.

This is giving me a headache.

What is all of this even about?

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📝Key Phrases

music to your ears

take it easy

catch up on reading

rolling out the red carpet

can't quite put my finger on it

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📖 Transcript

Grownups, Wondery Plus subscribers can listen to Wow in the World early and ad-free right now.

Join Wondery Plus in the Wondery app or Wondery Kids Plus on Apple Podcasts.

Hey, Wowzer fans, Mindy here.

And before we start the show, I gotta let you know that this November, with a special new episode featuring our friends at Circle Round and Terrestrials on Radiolab for Kids,

And don't miss when Elmo from Sesame Street stops by Wow in the World to make us all belly laugh on November 24th.

Oh, but that's not all, Reg.

And parents, if you want to upload any photos or videos or messages to us, please visit wowintheworldcom and find a link where you can do just that, and if you haven't already done so, please subscribe on apple podcast or however you get your podcasts, leave us a few stars and a review and be sure to tell a friend about the show.

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