Vitamin D deficiency Nutritional, Metabolic, Endocrine
Conditions
Interventions
Participants were allocated randomly to the two study conditions as much as possible. This was, however, not possible for several participants as they either changed in their work location or amount o
Sponsors
Signify (Netherlands)
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: 1. Aged =18 years 2. Fitzpatrick skin type II or III 3. Living in/around Eindhoven 4. Medically fit to work the hours as contractually agreed 5. Desk presence (at the home office) of at least 2.5 days per week during the 8 weeks study 6. Finding it no problem to have blood drawn three times over a period of 8 weeks
Exclusion criteria
Exclusion criteria: 1. Current pregnancy, breast feeding or a desire to become pregnant 2. Having children at home aged 10 years or younger 3. Having malignant skin conditions in the past or currently 4. Photosensitive medical conditions or photo-sensitising drugs 5. Users of medicines and/or crèmes mentioning in the prescription as side effect extra sensitivity to the sun/interaction with sun exposure 6. Planned use of sun beds, or sunbed use during the past 4 weeks 7. Currently taking or planning to take oral vitamin D3 supplements or have been taking D3 supplements during the past 4 weeks 8. High vitamin D levels at the start of the study (>375 nmol/l) which need medical attention
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Serum 25(OH)D level measured using blood sampling and automated immunoassay at baseline, 4, and 8 weeks | — |
Secondary
| Measure | Time frame |
|---|---|
| Sleep duration, midsleep timing, sleep quality, and fatigue measured using participant questionnaire at baseline, 4, and 8 weeks | — |
Countries
Netherlands
Outcome results
None listed