Unpacking Ultraprocessed Foods

Aug 28

This week on Your Diet Sucks, Kylee and Zoë take a deep dive into ultra-processed foods: what they are, where they came from, how they’re engineered to light up your brain’s reward systems, and what role they play in everyday nutrition.

We cover everything from cereal designed to “prevent sinning,” to the low-fat diet craze, to the wartime origins of shelf-stable food. We also unpack the science behind hyper-palatable foods and why they’re so hard to resist.

Plus, we dig into the landmark NIH study showing how the degree of food processing, not just calories or macros, can shape appetite, fullness, and how our bodies respond to food. This episode will help you understand the systems at play so you can make choices that support health and performance without falling into fear or shame.

Because when it comes to ultra-processed foods, context matters, whether you’re an athlete, a weekend warrior, or just trying to eat a little better.

SOURCES:

Hall, K. D., Ayuketah, A., Brychta, R., Cai, H., Cassimatis, T., Chen, K. Y., ... & Zhou, M. (2019). Ultra-processed diets cause excess calorie intake and weight gain: An inpatient randomized controlled trial of ad libitum food intake. Cell Metabolism, 30(1), 67–77.e3. https://doi.org/10.1016/j.cmet.2019.05.008

Monteiro, C. A., Levy, R. B., Claro, R. M., de Castro, I. R. R., & Cannon, G. (2009). A new classification of foods based on the extent and purpose of their processing. Public Health Nutrition, 12(7), 1031–1036. https://doi.org/10.1017/S1368980008003762

Sinclair, U. (1906). The jungle. New York, NY: Doubleday, Page & Company.

United States Senate Select Committee on Nutrition and Human Needs. (1977). Dietary goals for the United States (2nd ed.). Washington, D.C.: U.S. Government Printing Office.

Moss, M. (2013). Salt sugar fat: How the food giants hooked us. New York, NY: Random House.

Specter, M. (2025, January 13). Why is the American diet so deadly? The New Yorker.

Snackwell effect. (n.d.). In The Decision Lab. Retrieved March 2025, from https://thedecisionlab.com/biases/snackwell-effect

Zoë Rom

Zoë Rom is a science and environmental journalist with bylines in The New York Times, Outside, and High Country News. She co-hosts Your Diet Sucks, an evidence-based nutrition and wellness podcast, with registered dietitian Kylee Van Horn, RDN, where they investigate how wellness culture distorts science and how athletes can do better. A Colorado-based ultrarunner, she finished second at the Leadville Trail 100 and top five at Run Rabbit Run 100. Her reporting and commentary focus on the intersection of sport, science, and the wellness industry's long history of selling women their own anxieties.