Dietary changes in Western society highlight the need for individual and collective health providers to use their strategic positions to actively promote healthy eating habits. Using the research-action methodology in various clinics in the Federal District of Brazil, the present study aimed to identify what these professionals consider a healthy diet. The results indicate an apparent conceptual dichotomy: on the one hand, an idealized version of eating for good health based on the scientific literature; on the other, a concept derived from the ideal, but based on people's day-to-day reality. In their pursuit of the latter concept, people in social situations make connections between various pieces of information, and what emerges are the eating habits most closely associated with a particular lifestyle. However, both concepts tend to transcend the implicit biological character of the conceptual constructs and to find support in the sociocultural conditions that shape them and which in turn are shaped at the concrete level of reality.