Freakonomics Radio: EXTRA - The Downside of Disgust (Update) Release Date: March 5, 2025
Host: Stephen J. Dubner
Guests:

• Paul Rozin: Professor of Psychology at the University of Pennsylvania
• Val Curtis: Professor at the London School of Hygiene and Tropical Medicine
• Sandro Ambuhl: Economist at the University of Zurich
• Emily Kimmins: R&D Lead for Sensory and Consumer Science at Kraft Heinz

Introduction

In this special archival episode of Freakonomics Radio, host Stephen Dubner revisits a compelling discussion initially conceived in early 2020 but shelved due to the pandemic. Titled "The Downside of Disgust," the episode delves into the multifaceted nature of disgust, its evolutionary roots, its impact on human behavior, and the potential consequences of its influence in the modern world.

Understanding Disgust: An Evolutionary Perspective

[00:01 - 03:19]
Dubner opens with thought-provoking questions about the universality of disgust, using the example of refusing to eat insects despite their nutritional benefits. This sets the stage for exploring why certain things elicit disgust and whether these reactions are universal or culturally specific.

Notable Quotes:

• Val Curtis ([02:16]): "Fecal material, for example, is inherently disgusting. Every person on the planet, with a few strange exceptions, finds fecal material something they want to stay away from."
• Paul Rozin ([02:31]): "There are enormous variations in disgust."

Dissecting Disgust: Insights from Experts

[04:11 - 07:09]
Paul Rozin, a pioneer in disgust research, discusses the evolutionary basis of disgust, emphasizing its role in avoiding pathogens. Rozin highlights the paradox of humans loving meat—a highly nutritious but often tabooed food—raising questions about the complexities of disgust responses.

Notable Quotes:

• Paul Rozin ([10:22]): "Disgust was originally defined as a rejection or offense at the oral incorporation of an offensive substance."
• Val Curtis ([09:55]): "Being an evolutionarily minded sort of person, I saw that disgust is basically an adaptation to make us behave in ways that avoid us getting sick."

Categories and Expressions of Disgust

[08:01 - 14:38]
Val Curtis outlines six categories of disgust: hygiene, certain animals and insects, sexual disgust, specific food types, and more. The discussion extends to the physical manifestations of disgust, such as the "disgust face," and the universal verbal expressions like "ugh" or "blech."

Notable Quotes:

• Val Curtis ([10:54]): "There's disgust about hygiene... disgust related to certain types of animals and insects... sexual disgust related to people who are atypical in their appearance..."
• Paul Rozin ([13:27]): "That's a little different from saying that someone who burns the American flag is disgusting."

The Malleability of Disgust

[14:38 - 15:11]
Curtis and Rozin discuss how disgust is not a static emotion. Factors like hunger or sexual arousal can modulate disgust responses, demonstrating its adaptability based on situational needs.

Notable Quotes:

• Val Curtis ([14:53]): "Our motives compete for our attention at every moment, and the one which is the strongest is the one that's going to win."
• Sandro Ambuhl ([15:30]): "It's the trade-off that you're making that's going up and down."

Disgust's Role in Public Health

[16:12 - 20:33]
Curtis shares a successful hand-washing campaign in Ghana that leveraged disgust without explicitly mentioning germs. By visually showing the contamination of food with feces, the campaign effectively doubled hand-washing rates, illustrating disgust's power in promoting public health measures.

Notable Quotes:

• Val Curtis ([19:33]): "It was a really powerful disgust message."
• Val Curtis ([20:24]): "This was one of the most effective hand washing campaigns ever."

The Economics of Disgust: Incentives and Repugnance

[24:56 - 30:28]
Sandro Ambuhl explores the intersection of economics and disgust, particularly how financial incentives can influence disgust-driven decisions. His experiments reveal that higher monetary rewards can lower the disgust threshold, leading individuals to overcome their aversions. However, Rozin warns that such incentives might hinder long-term acceptance of desired behaviors, like consuming insects.

Notable Quotes:

• Sandro Ambuhl ([28:15]): "I wanted to know, if I offer incentives to somebody, what do I do with their quality of decision."
• Paul Rozin ([30:28]): "If you pay people to eat insects, they're less likely to engage with it after you remove the payment."

Overcoming Disgust: Experiments and Applications

[30:40 - 33:37]
The discussion shifts to practical applications of mitigating disgust. Rozin and Curtis highlight the mere exposure effect, where repeated exposure reduces disgust responses. Curtis mentions traditional practices, such as eating fried flying ants in Uganda, which minimize the association between insects and disease.

Notable Quotes:

• Paul Rozin ([30:50]): "Just as you are exposed to something over longer and longer time periods, you start liking it."
• Val Curtis ([32:07]): "Once you've fried them and salted them and you're having them with a few beers, the wriggly, sticky, gooey nature of insects is rather forgotten."

Insects as a Case Study: Challenges and Opportunities

[33:37 - 47:38]
The episode delves deep into the proposition of integrating insects into mainstream diets. Emily Kimmins from Kraft Heinz discusses the challenges of consumer acceptance, emphasizing the "ick factor" and the importance of blending familiar and unfamiliar flavors. Rozin shares insights from trying insect-based dishes, noting the potential for gradual acceptance through culinary innovation.

Notable Quotes:

• Emily Kimmins ([37:09]): "Consumers need something physical to touch and taste and hold onto to tell you what they like and what they don't like."
• Paul Rozin ([44:50]): "If people didn't know what they were eating, they might think it was pretty good."

Future Implications and Conclusions

[47:36 - 49:31]
The conversation concludes with reflections on the feasibility of making insects a staple in diets worldwide. While progress has been made, such as the EU's approval of insect proteins, significant cultural and perceptual barriers remain. Rozin and Ambuhl express cautious optimism, suggesting that with continued exposure and culinary creativity, insects could become more widely accepted.

Notable Quotes:

• Sandro Ambuhl ([43:44]): "I do think it's going to be very, very hard to convince even a sizable minority of the population to consume insects on a regular basis."
• Emily Kimmins ([46:51]): "If you can blend it with something they already know they already like, you have a better chance of getting new flavors into their repertoire."

Epilogue

The episode wraps up with somber notes, mentioning the closure of the Black Ant restaurant and the passing of Val Curtis in October 2020 due to cancer. Dubner pays tribute to Curtis, acknowledging her significant contributions to the field of disgust research.

Key Takeaways

• Evolutionary Roots: Disgust serves as a protective mechanism against pathogens and harmful substances.
• Cultural Variability: While some disgust responses are universal, many are shaped by cultural norms and personal experiences.
• Behavioral Influence: Disgust can both deter negative behaviors (like avoiding contaminated food) and hinder positive changes (like adopting sustainable practices).
• Malleability: Disgust is not fixed; it can be modulated by factors such as incentives, exposure, and context.
• Practical Applications: Leveraging disgust in public health campaigns can be highly effective, but caution is needed when using incentives to alter disgust-driven behaviors.
• Future Prospects: Integrating insects into diets remains challenging but not impossible, requiring innovative culinary approaches and gradual cultural shifts.

Conclusion

"The Downside of Disgust" offers a nuanced exploration of an emotion deeply ingrained in human behavior. By understanding its origins, applications, and limitations, we can better harness disgust's power to promote health and sustainability while being mindful of its potential drawbacks in fostering resistance to beneficial changes.

Notable Contributors:

• Produced by: Matt Hickey, Daphne Chen, Dalvin Abuaji
• Freakonomics Radio Network Staff: Alina Cullman, Augusta Chapman, Eleanor Osborne, Ellen Frankman, Elsa Hernandez, Gabriel Roth, Greg Rippon, Jasmine Klinger, Jeremy Johnston, John Schnarz, Morgan Levy, Neal Carruth, Sarah Lilly, Teo Jacobs, Zach Lipinski
• Theme Song: "Mr. Fortune" by The Hitchhikers
• Composer: Luis Guerra

For more episodes and transcripts, visit freakonomics.com.