OBJECTIVES This study was undertaken to test the effectiveness of the Stanford Nutrition Action Program, an experimental trial to reduce dietary fat intake among low-literacy, low-income adults. METHODS Twenty-four paired adult education classes (351 participants, 85% women, mean age = 31 years) were randomly assigned to receive a newly developed dietary fat curriculum (the Stanford Nutrition Action Program) or an existing general nutrition curriculum. Food frequency and nutrition-related data, body mass index, and capillary blood cholesterol were collected at baseline and at two postintervention follow-ups. RESULTS The Stanford Nutrition Action Program classes showed significantly greater net improvements in nutrition knowledge (+7.7), attitudes (/0.2), and self-efficacy (-0.2) than the general nutrition classes; they also showed significantly greater reductions in the percentage of calories from total (-2.3%) and saturated (-0.9%) fat. There were no significant differences in body mass index or blood cholesterol. All positive intervention effects were maintained for 3 months postintervention. CONCLUSIONS The Stanford Nutrition Action Program curriculum, tailored to the cultural, economic, and learning needs of low-literacy, low-income adults, was significantly more effective in achieving fat-related nutritional changes than the general nutrition curriculum.