The aim of this study was to assess whether a programme promoting diet and physical activity in the workplace—at the Policlinico Umberto I Hospital and Sapienza University of Rome—could change employees’ knowledge of nutrition and physical activity, as well as their attitudes towards food choices and exercise, thereby leading to a reduction in body weight and waist circumference. Another fundamental aspect was to increase employees’ knowledge of the Mediterranean diet and verify possible improvements in eating habits.

The results show that participants achieved a significant reduction in body weight, with group D showing the best results. There were also clear changes in eating habits, such as a reduction in the consumption of fast food, cured meats, sweets, and red meat, associated with an increase in the consumption of fruit, legumes, and whole grains. On the basis of the results, the effects appear to be comparable to those in a study by Viester et al. (2018). The latter study was conducted among construction workers in the Netherlands, where personalized coaching led to a reduction in body weight at 6 months and 12 months. The weight reduction was lower than in our intervention, and it should be noted that the Dutch study used a different approach, combining individual coaching sessions and tools such as pedometers and BMI calculators, while our intervention focused on structured dietary changes and viewing videos and informational material. In the Full Plate Living (FPL) programme, a dietary intervention featuring mainly plant-based foods led to weight loss. Although the weight loss was similar to that observed in our study, our target population followed a low-calorie Mediterranean diet rather than a predominantly plant-based diet. This suggests that interventions with diets based on more flexible and balanced eating plans, such as the one adopted in our study, may be as effective in promoting weight loss as more restrictive or food-specific programmes (Kelly et al. 2023).

With regard to knowledge about physical activity, the results show an improvement only for group B (those who followed the diet and watched the videos on the Mediterranean diet), although the change was not significant. On the other hand, with regard to the level of physical activity—the subject of the trial—analysis of the data from the IPAQ-SF questionnaire shows a decrease in the time spent walking but in particular in moderate physical activity; these reductions were offset by an increase in vigorous physical activity, so that the total MET remained unchanged. Ultimately, there was no significant impact on physical activity in the four study groups. A recent study by Oppermann and Dierks (2023) explored the effectiveness of a health promotion programme based on physical exercises that could be performed in the workplace. While focusing primarily on physical activity, the study emphasized the importance of a digital and flexible approach to engaging participants. In addition to the videos, once a day, all participants received an email reminding them of the videos and encouraging them to take a short exercise break. As in our study, the results of Oppermann and Dierks (2023) suggest that digital support and video instructions could be an additional tool to improve participation and the effectiveness of health promotion interventions in work settings. The results also show a significant reduction in waist circumference, particularly in the group that, in addition to the diet, watched videos related to physical activity. These results accord with those reported in a systematic review conducted by Peñalvo et al. (2021), which examined workplace wellness programmes and found an overall reduction in BMI and waist circumference. These results confirm that workplace health promotion programmes can have a positive impact on cardiometabolic risk factors, as already highlighted by the positive changes in eating habits observed in our study.

In a similar study in Italian healthcare workers, the adoption of a personalized diet programme led to a significant reduction in BMI, along with improvements in eating habits and adherence to a Mediterranean diet. Our study found a comparable reduction in body weight. This suggests that interventions based on personalized dietary approaches may be particularly effective in a work setting, regardless of profession. One difference between the previous study and ours is with regard to employee dropout from the study. However, as the authors noted, the small size of the hospital where the study was implemented may have been a determining factor in the results: the hospital structure featured well-connected pavilions, with high standards of internal communication between the various operating units. In our case, the size and complexity of the hospital and Sapienza University of Rome may have been a decisive factor in the number of dropouts during the follow-up (Rapisarda et al. 2021).

With regard to the BMI parameter, our study found a significant decrease in this parameter from time T3 to time T1, especially in the study arm consisting of individuals who watched videos on diet and physical activity in addition to following a diet plan. A study conducted by Thomson et al. (2018) showed similar results, with a significant reduction in BMI and visceral fat, using online nutrition education programmes for workers. In a study conducted by Rapisarda et al. (2021) in Italian healthcare workers, the adoption of a personalized diet programme led to a significant reduction in BMI, along with improvements in eating habits and adherence to the Mediterranean diet. Our study, while focusing primarily on a face-to-face dietary intervention, achieved comparable results, suggesting that both online and face-to-face interventions can be valuable tools for promoting weight loss and improving health in the workplace.

This study has several strengths. First, the programme offered to employees provided an effective approach to behavioural change aimed at improving lifestyle, with the great advantage of always having a dietitian as a point of reference for doubts, questions, and specific requests regarding diet. The project provided a valuable opportunity to learn concepts that are often ignored or taken for granted, about which false myths often circulate that generate misinformation and can lead people to adopting unhealthy behaviours. Integrating an educational approach within typical workplace wellness programmes helped improve the likelihood of adopting new behaviours, increasing participants’ confidence.

In addition, the programme focused primarily on changing health-related behaviours, rather than focusing solely on metabolic profiling, with the potential to foster improvements in health and lifestyle issues by going beyond simply monitoring traditional metabolic parameters.

In addition, the grouping of participants into four arms made the study more robust and convincing; this subdivision made it possible to differentiate the various interventions by emphasizing the diversity of outcomes between groups and to understand which intervention was most effective.

On the other hand, this clinical study also had some limitations. The first limiting factor was the loss of participants during follow-up, but also the duration of follow-up itself, which may be insufficient to fully assess the long-term effects of behavioural modifications and changes in anthropometric parameters, albeit still acceptable for testing the effects of the intervention. Future studies with longer follow-ups and repeated measures of anthropometric indices would provide a better understanding of the clinical relevance of our results and enable an assessment of their long-term maintenance, helping to strengthen adherence to the pathway.

An additional limitation is the possibility that external factors, such as subjective compliance with the programme or individual differences in lifestyle, influenced the results, making it more difficult to isolate the effectiveness of the programme per se.

In addition, physical activity was not measured objectively, but self-reported through questionnaires, which are not entirely accurate given the retrospective nature of the survey. Another limitation is highlighted by the feedback received from the study participants, in that some experienced difficulties in performing the proposed physical exercises, which should therefore be better adapted to any physical limitations of the individual. This adjustment could improve the accessibility and effectiveness of the programme, ensuring that all participants can benefit from the proposed exercises according to their individual conditions.

Consideration could also be given to creating a dedicated online platform where information documents could be uploaded in PDF format along with links to the videos; each video could be accompanied by a brief description of the content, and the platform could include a notification function to alert users when new videos have been uploaded. This approach would improve access to resources and facilitate communication with participants.

Finally, the use of a relatively small sample might limit the generalizability of the results of this intervention to other contexts. Thus, our results support the need for further studies to confirm the effectiveness of the intervention in different and larger populations.

The health promotion programme based on a Mediterranean-style low-calorie dietary approach resulted in a significant reduction in body weight in all groups and improvements in eating habits, confirming the initial hypothesis. This highlights the potential of structured workplace interventions, in combination with informational support, in optimizing worker health. The results are in line with previous research, showing that flexible, individually tailored dietary approaches can be as effective as more restrictive ones in promoting health.

Although the intervention did not result in a reduction in sedentary behaviour, there is evidence that workers were made aware of health issues and showed greater interest and commitment to healthier food choices and regular physical activity. From the results, it appears that the informational material regarding physical activity was not sufficient to increase the level of exercise, so a new instructional plan should be formulated to increase exercise.

A health-friendly corporate culture is critical to the success of such programmes. Companies that encourage an active work environment and provide resources for proper nutrition contribute to a climate of well-being, strengthening the bond between employees and the organization. Critically, the design of such interventions should aim not only for an immediate impact but also for sustainability in the long term; this requires constant monitoring and adaptation of strategies to the needs of employees and business dynamics.

All companies should invest in health promotion programmes that include physical activity, access to healthy foods, and continuing education on the benefits of a healthy lifestyle.

In conclusion, health promotion in the workplace not only promotes employee well-being but also results in tangible benefits for companies.

Future studies should examine the integration of digital and multimedia components, as evidenced by some of the studies cited earlier that have used digital platforms to promote physical activity and improve nutrition education in workers. In addition, it would be useful to conduct further research to assess the long-term impact of these interventions, including examining their effects on health-related quality of life and work productivity.