This study is an experimental design study in which demographic characteristics, food consumption, biochemical parameters and anthropometric measurements of individuals with low vitamin D levels before and after consuming UV-enriched foods will be examined.

It was designed to be applied to individuals with low vitamin D levels working in Fatih Sultan Mehmet Training and Research Hospital who meet the research conditions.

n the first phase of the study, demographic information will be recorded by asking demographic information from the people who volunteered to participate in the study and who meet the study criteria by using a questionnaire form and 3-day food consumption record information by face-to-face interview technique; anthropometric measurements of the participants will be taken and baseline blood values will be recorded. At the beginning of the experimental study, individuals will be randomized by computer-assisted randomization into four different groups. Biochemical analyses will be analyzed every two weeks, analyses will be repeated 1 month after the study and the effects of vitamin D enrichment on biochemical parameters will be determined.

Inclusion Criteria:

1. Working in the hospital
2. Being between the ages of 18 and 65
3. Not being pregnant or lactating
4. Not taking vitamin D supplements or fish oil in the last 1 month
5. Serum 25(OH)vitamin D value below 30 μg/L
6. No kidney disease, kidney stones, cortisone use, blood thinners
7. Not being in a solarium
8. Not eating fish more than once a week
9. Volunteering to participate in the research

Exclusion Criteria: