Respiratory and gastrointestinal infections are frequent problems in children under 4 years of age, especially after the start of schooling. These conditions are facilitated by an incomplete maturation of the immune system and by the anatomical and functional structure of the respiratory and gastrointestinal tract still in development.

Functional foods derived from the fermentation of cow's milk with probiotic strains have been proposed for the prevention of infectious diseases in children. Several products have been investigated, sometimes with conflicting results. Some scientific evidence has shown that the administration of Vitamin D, Zinc, Beta glucan, 2'-Fucosyllactose can stimulate the immune defenses and reduce the number and severity of infectious episodes. In particular, 2'-fucosyllactose is one of the oligosaccharides of breast milk. It has both a prebiotic and immunoregulatory action since it is able to prevent the adhesion of pathogens to epithelial surfaces and subsequent translocation.

Healthy school-going children aged between 12 and 48 months, who attend school at least 5 days a week, will be evaluated.

Inclusion Criteria:

• Healthy school-going children aged 12 to 48 months who attend school at least 5 days a week

Exclusion Criteria:

• Age less than 12 months and more than 48 months;
• Concomitant presence of chronic diseases
• Congenital heart disease;
• Tuberculosis;
• Functional gastrointestinal disorders;
• Gastrointestinal or urinary surgery of the respiratory tract;
• Autoimmune diseases;
• Immunodeficiencies;
• Chronic inflammatory bowel diseases;
• Celiac disease;
• Cystic fibrosis;
• Metabolic diseases;
• Lactose intolerance;
• Tumors;
• Chronic lung diseases and malformations of the gastrointestinal tract;
• Food allergies;
• Eosinophilic esophagitis;
• Other hypereosinophilic diseases of the gastrointestinal tract;
• Diarrhea at enrollment;
• Severe malnutrition (z score for weight/height less than 3SD);
• Taking antibiotics and/or pre/pro/symbiotics/immunostimulants within 2 weeks of starting the study;
• Breastfeeding in progress

Nobody knows the randomization code