The PRENAV project focuses on healthy and sustainable eating among employees in the defense sector of the Republic of Slovenia. The project pursues two main objectives:

1. In a selected sample of employees in the defense sector, the project will determine their nutritional status and assess indicators of metabolic health, including serum concentration of vitamin D.
2. In the selected sample, through a survey and qualitative methods (interviews, focus groups), we will identify the eating habits of employees in the defense sector, the factors influencing their dietary decisions, and the barriers and facilitators of healthy and sustainable eating among employees in the defense sector.

Based on these findings, we will prepare recommendations and an action plan to promote healthier and more sustainable eating among employees in the defense sector.

Participants will be selected using non-probability quota sampling, with quotas defined according to population characteristics, taking into account the research problem:

1. Proportional representation based on the permanent composition of employees in the defense sector: soldiers, non-commissioned officers, officers, and military staff (military personnel 70%) and civilian employees (30%).
2. Eating habits (canteens) during working hours: based on the number of employees at each military barracks (n=13) and at the Ministry of Defence.
3. Gender structure of the observed population: military personnel 85% male and 15% female; civilian employees according to the gender distribution data of the civilian workforce.
4. The purpose of this sampling strategy is to proportionally capture those characteristics of the military and civilian population employed in the defense sector that are crucial for the research objectives, namely: employment structure, gender distribution, and eating habits in canteens.

Inclusion Criteria:

• Adults employed at the Ministry of Defence or in the military.
• Asymptomatic individuals (i.e., without current acute illness or relevant health complaints).
• Willingness to provide informed consent to participate in the study.
• Willingness and ability to complete all questions in the Food Frequency Questionnaire (FFQ) and other study questionnaires.

Exclusion Criteria:

• Pregnant and breastfeeding women, as well as individuals with electronic implants such as a pacemaker, will be excluded.

All participants will be adults, with an expected age range of 18-65 years, including both males and females, employed in the defense sector. Participants will include both military personnel and civilians.