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

Wow in the World · B1 · 2021-03-08

📋 Summary

The Biology of Bitter: Why Your Palate Can Change

In this episode of Wow in the World, hosts Mindy and Guy Raz explore the fascinating biological connection between our saliva and our willingness to eat bitter foods. While most people naturally gravitate toward sweet or salty flavors, bitter foods like kale, Brussels sprouts, and dark chocolate are often perceived as unpleasant. However, recent scientific research suggests that our taste preferences are not fixed—they can actually be trained.

The Bitter Truth About Taste Buds

Dr. Cordelia Running, a researcher from Purdue University, spearheaded a study to understand why humans generally reject bitter-tasting foods. Bitter is considered the most "unpleasant" of the five basic tastes (the others being salty, sweet, sour, and umami). Despite being packed with essential vitamins and antioxidants, these foods are rarely a favorite for children. The central question of the experiment was whether this rejection is purely psychological or if it can be altered biologically by changing how our taste buds function.

The Chocolate Milk Experiment

To test her hypothesis, Dr. Running conducted an experiment with 64 participants. They were tasked with drinking chocolate milk—specifically made with cocoa containing only 4% sugar—every day for one week. Because of the low sugar content, the drink was intentionally bitter. The goal was to see if consistent exposure would change the participants' perception of the flavor over time. By the end of the week, the results were clear: most participants began to enjoy the drink, suggesting that their bodies had physically adapted to the bitterness.

The Role of Saliva and Proteins

The breakthrough in this study lies in the function of saliva. Saliva is more than just a liquid to help us chew; it is filled with tiny molecules called proteins that interact with the chemicals in our food to help us perceive taste. Dr. Running’s team discovered that as participants consumed the bitter cocoa, their saliva glands began to produce more of specific proteins. These proteins acted as a buffer, "dampening" or decreasing the intensity of the bitter flavor.

In essence, the body learns to adapt to the environment. The more the participants' saliva came into contact with the bitter compounds, the more the saliva composition changed to make those flavors less offensive to the brain. This suggests that the old adage "you have to try it seven times" might actually have a biological basis—your saliva needs time to adjust its protein production to help you tolerate and eventually enjoy healthier, bitter foods.

Conclusion

This scientific discovery highlights a powerful takeaway: our food preferences are not set in stone. As Guy Raz, the self-proclaimed "kale crusader," realized, his lifelong love for vegetables might be the result of years of exposure that physically altered his biology. By consistently eating foods we think we dislike, we may be training our saliva to change the way we experience taste, ultimately allowing us to expand our palates and embrace a healthier 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.

I was just planning on taking it easy today.

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📝Key Phrases

music to your ears

take it easy

catch up on reading

roll 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.

Or study on the web version →