Radiolab
Radiolab

The Sweetest Thing

September 18, 2026

AI Summary

5 min read

The Sweetest Thing

When journalist Latif Nasser was driving with his two young children, the U2 song "The Sweetest Thing" came on. His kids, then six and three, weren't interested in the romantic answer. They wanted to know: what is literally the sweetest thing you can put in your mouth? Nasser, thinking this would be a simple question with a straightforward answer, set out to find it. What he discovered was that the hunt for the sweetest thing leads not to a single substance, but through chemistry, perception, evolution, and even outer space.

The Chemist's Ranking

Nasser first turned to Eric Walters, a biochemist who spent years developing artificial sweeteners at NutraSweet. Walters walked him through the standard industry ranking of sweeteners, using table sugar as a baseline. Honey comes in at 1.5 times sweeter than sugar. Aspartame—the sweetener in Equal—is 200 times sweeter. A West African berry called katemfe fruit is 2,000 times sweeter. Then there's advantame, which is 20,000 times sweeter than sugar—meaning a pinch could sweeten 500 gallons of water. And at number one: lugduname, a synthetic molecule that is 300,000 times sweeter than sugar.

Continue reading the full summary in the app — free to try.

Read Full Summary →

Free • No credit card required

Listen to Audio Summary Open in App

What you'll learn

  • 1 The Sweetest Thing — Radiolab
  • 2 Timestamped Outline
  • 3 (02:00) **The Kid Question** - Latif Nasser explains how his kids asked a deceptively simple question: what is the sweetest thing you can put in your mouth?
  • 4 (04:06) **The Official Ranking** - Biochemist Eric Walters walks through the top five sweetest substances ranked by potency, using table sugar as the baseline
  • 5 (09:42) **The Ranking Is "Ridiculous"** - Psychologist Linda Bartoshuk and food scientist Paul Breslin explain why the potency list misses the point
  • 6 (11:35) **Intensity vs. Potency** - The real question is about perceived intensity, not how little you can use
  • 7 (13:01) **The Profound Answer** - Sugar might actually be the sweetest thing, and there's an evolutionary reason for that

+ Full timestamped outline available in the app

Guests on this episode

Latif Nasser

Show Notes

“What is the sweetest thing in the world?” After co-host Latif Nasser’s sons ask him this deceptively simple question, he goes on a quest to find it. Is it a West African Katemfe berry? Or an industrial sugar substitute cooked up in a lab? Or an ingredient hiding in plain sight in all of our pantries? A simple mystery that will make you question what sweetness even is, how our tongues (and other body parts you wouldn’t expect) determine what we like, and how far you would go to taste something sweeter than anyone has ever experienced. 

Thank you to Latif’s sons for indulging us, to Nicola Twilley and Cynthia Graber at Gastropod, to Anni Laffitte, Nazli Parvizi at Museum of Food and Drink, to food icons Claire Saffitz and Sam Seneveratne who did a live show version of this episode with us at the Tribeca Festival. And thank you to Davy Gardner and his wonderful team of audio folks at the Tribeca Festival.

Thank you to Jialin Deng who composed the song that was our ‘sonic seasoning’. And to Laura Rickman and everyone else at Columbia University’s Mortimer B Zuckerman Mind Brain Behavior Institute for hosting us. 

And big thanks to experimental psychologist Charles Spence at Oxford, sweetness chemist Grant DuBois, Danielle Reed at Monell Chemical Senses Center, and nutritional scientist Sarah Berry at King’s College London who all talked to us about their research. And Brian Everett of Honest Organic Farms.

And a very special thanks to Sean Oomens, inventor of producer Jess Yung’s favorite candy, nerd gummy clusters

EPISODE CREDITS: 
Reported by - Latif Nasser
with help from - Jessica Yung
Maria Paz Gutierrez, Jessica Yung, Ekedi Fausther-Keeys, Natalia Ramirez??
Produced by - Jessica Yung 
with help from -  Mona Madgavkar, Maria Paz Gutierrez, Gabby Santas, and Maia Appleby Melamed
with mixing help from - Jeremy Bloom
Fact-checking by - Sophie Samiee
and Edited by - Pat Walters

EPISODE CITATIONS:

Videos:

Articles -

Radiolab

More from this podcast

 Radiolab →