As global soybean production races ahead of its own nutritional promise, a team of researchers working across three continents has found a quiet but consequential clue inside the seed itself: the minerals zinc and sulfur appear to govern how much protein a soybean can build. The discovery, made visible through synchrotron imaging at facilities in Canada and Brazil, suggests that feeding the world more sustainably may not require more land — only a more precise understanding of what the soil must offer at the right moment.