To define a low-risk diet for breast cancer in Italy, a multicentric case-control study of 2569 incident cases of breast cancer and 2588 controls from Italy was analyzed. A logistic regression model was applied to the estimated intake of five macronutrients and used to compute a diet-related risk score (RS). The pattern of macronutrient and food group intake across RS deciles was defined. The mean of diet-related RSs across subsequent risk deciles ranged from 0.83 to 1.44. Total energy intake first decreased slightly, from the first to the second decile, and then increased, mostly in the last three risk deciles. Intake of starch increased in absolute and relative terms, whereas saturated fat intake rose in absolute terms but remained stable as a proportion. A relative decline was observed for unsaturated fat and sugars, with a hint, however, of U-shape effect. From a food group viewpoint, there was a marked increase in the intake of bread and cereal dishes, cakes and desserts, and refined sugar across subsequent deciles, whereas the consumption of vegetables, olive and seed oils, and fruit decreased.