In this episode of Science Quickly, Rachel Feltman speaks with environmental historian Edward Melillo about the tiny soybean, which has come to dominate America’s diet. When you think of soy, you may only picture a block of yummy tofu or soy milk, but this crop has quietly made its way into 60 percent of processed foods. In fact, 2026 is on track to become a record soybean harvest for the U.S. And soy doesn’t just show up on our plates: as an oil, it can power trucks, buses and even planes. Tune in to hear how this plant took over the American food system. Recommended Reading:How Seed Oils Became Controversial—And What the Science Really SaysWhy corn isn’t entirely to blame for ‘corn sweat’E-mail us at [email protected] if you have any questions, comments or ideas for stories we should cover!Discover something new everyday: subscribe to Scientific American and sign up for Today in Science, our daily newsletter.Science Quickly is produced by Rachel Feltman, Fonda Mwangi, Sushmita Pathak, Allison Rodgers and Jeff DelViscio. This episode was edited by Alex Sugiura, with fact-checking by Marielle Issa and Aaron Shattuck. Our theme music was composed by Dominic Smith.Learn more about your ad choices. Visit megaphone.fm/adchoices