While medical research ethics guidelines frame participants as individual and autonomous, anthropologists emphasize the relational nature of health research participation. I analyze interviews with Mexican male HPV study participants and their wives to examine how research participants themselves focus on relationships when imagining research-related benefits. I argue that couples incorporated the local trope of the Mexican citizenry as a biologically homogeneous national body, which individual members help or harm through their gendered health behavior to understand these benefits. I use the concept of “ethical intercorporeality” to discuss spouses’ understandings of themselves as parts of bio–social wholes—the couple, family, and society—that they believed men’s research participation could aid both physically and socially. This finding extends the insight that focusing on relationships rather than individuals is necessary for understanding the consequences of medical research by showing how participants themselves might apply this perspective in context-specific ways.