This controlled trial aims to assess the impact of personalization and digitalization on the development of skills related to food agency, safe dietary habits, and healthy lifestyles in a cohort of 120 free-living individuals aged 65 years and older. Participants are assigned to intervention and control groups to evaluate the effectiveness of tailored interventions leveraging personalized and digital approaches.

The "proof of principle" study was a one-year, three-arm controlled trial conducted in free-living men and women over 65 years old living in Madrid, Spain. The study aimed to answer the following questions:

i) Did personalization of dietary and lifestyle advice improve diet and food literacy, promoting healthy lifestyles? ii) Was the use of a specifically designed mobile app effective in assisting and/or motivating study participants to make and sustain appropriate health-promoting changes? To answer these questions, participants were assigned to a Control group (Level 0) or to one of two intervention groups for a one-year period.

Participants were recruited in Cultural associations in Fuenlabrada, a town in southern Madrid. A cluster sampling was carried out, randomly selecting three centers from among the eight Cultural Centers for the Elderly existing in Fuenlabrada. One center acted as a control center, while the other two provided the sample of seniors who were the subjects of the interventions (one center for L1 (personalization) and another for L2 (personalization and digitalization)). Adequate distance between the selected centers was ensured to avoid cross-contamination between participants. Participation in the project was offered to all users of the selected centers who met the inclusion criteria, up to the number of participants required for the project.

Inclusion Criteria:

• Age 65 years and over
• Non-institutionalized
• Retired from main professional activity or part-time working
• Smartphone user.

Exclusion Criteria:

• Presence of a severe or limiting disease (such as cancer, dementia, advanced Parkinson's disease, or any other serious pathological condition)
• Use of a pacemaker or implantable automatic defibrillator
• Adherence to a specific prescribed diet for any reason other than a low-sodium, low-fat, or weight-control diet.
• Diagnosis of digestive disorders such as celiac disease or Crohn's disease, or any metabolic disease or condition that alters nutritional requirements.
• Use of enteral or parenteral nutritional support at home.
• Presence of cognitive or psychomotor impairment.
• Expectation of institutionalization.
• Consumption of more than five main meals per week outside the home