Abstract Background Type 2 diabetes (T2D) is associated with a prion diminished quality of life, especially due to the severe complications that it implicates. Changing dietary habits is an absolute priority, as well as implementing nutritional motivational programs. The aim of this study was to verify the effectiveness of a nutritional intervention in improving the health of patients affected by T2D. Methods A total of 69 patients participated in a nine-months motivational program focused on the principles of the Mediterranean diet, the classes of nutrients, the distribution of the meals during the day and the dietary choices. During regular meetings, the patients were requested to fill out a questionnaire about their dietary habits and behaviours. Clinical and metabolic parameters were also analysed. Results At the end of the intervention the number of people who declared that they ate five meals a day (p = 0.006) and preferred to have fruit for snack (p = 0.004) increased, while there was a reduction in the use of sweeteners and an elimination of the use of fructose (p = 0.05). The total daily consumption of kilocalories (kcal) had been reduced and the percentages of carbohydrates, proteins and lipids, after the intervention, follow the guidelines. In relation to this, a significant improvement (p