The purpose of this study was to determine the effects of a nutrition-education program provided by a physician nutrition specialist in a family-practice residency program on residents' and faculty members' nutrition knowledge and nutrition-related patient care, their patients' perceptions of the importance of nutrition, and the physicians' dietary patterns. The nutrition specialist provided recommendations for nutrition patient-care practices to the physicians for 6 mo. Pre- and post-intervention assessments included 1) nutrition exams for physicians and patients, 2) patient questionnaires concerning attitudes towards nutrition, 3) chart reviews, and 4) diet records for physicians. The educational intervention caused a small but statistically significant (P < 0.01) increase in physicians' nutrition-knowledge scores and a significantly higher (P < 0.05) frequency of physicians discussing nutrition and recommending diets for their patients. Effects were greater among residents than among faculty members. The results suggest that a physician nutrition specialist can provide effective nutrition education within a residency program.