Methods: Two-hundred-fifty women (30–74 yr) with primary BC, participating in DEDiCa study (NCT02786875), were randomized into one of two treatments that included: recommendations on a traditional MeD with low GI carbohydrates (group A) or recommendations on a traditional MeD with whole grains (group B). At time 0 and 12 months, in a subgroup of 70 participants, we assessed dietary habits by food records and anthropometric and biochemical parameters by standard protocols.Results: Only 24% of participants showed high adherence to the MeD at baseline. Low adherence was found for fish, legumes, fresh fruit and nuts intakes while adherence to vegetables intake was medium. The differences at 12 months showed in both groups a significant reduction (p< 0.05) for calories (approximately 300 Kcal), glycemic load (28% group A, 15% group B), saturated fats (10% in both groups) and an increase for …