This study investigated the psychological wellbeing and body perception among young Italian people. Drinking, eating, and sexual behaviors have been examined in relation to body mass index (BMI) and psychological well-being by EPOCH framework. This was a cross-sectional observational study conducted on Italian adolescent and young adult population through an online survey. Qualitative and quantitative data on lifestyle, BMI classes, and psychological characteristics of wellness in youth were obtained from a sample of 1221 Italian participants using a self-report questionnaire on body perception and habits, a socio-demographics inventory, and the EPOCH measure. Findings suggest that being underweight or overweight is associated with various factors, including gender, self-control regarding food, perception of one’s body, and the happiness domain. EPOCH framework revealed the psychological wellness of girls and young women did not seem strongly affected by BMI, though Perseverance and Happiness seemed reduced with increasing BMI. The Engagement, Optimism, and Connectedness domains were not significantly affected by the BMI variable. On the contrary, Perseverance and Happiness seemed reduced with increasing BMI and were related to physical shape. Our study offers a new perspective: promoting the development of positive psychological characteristics since adolescence to boost quality of life by improving wellness, by EPOCH approach could be functional reinforcing specific psychological aspects in young generations regarding future wellness, improving the positive perception and management of their own health.