NCT03609970

Vitamin D and Immunity: Photosynthesis Versus Supplementation

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 36 (actual)
• Sponsor: Guy's and St Thomas' NHS Foundation Trust · Academic / Other
• Sex: All
• Age: 18 Years – 40 Years
• Healthy volunteers: Accepted

Summary

The optimal way to restore serum 25-hydroxyvitamin D sufficiency is currently debatable. UV irradiation through sunshine exposure promotes endogenous vitamin D synthesis, although this can also be associated with a risk of UVR-induced skin cancer. Dietary supplements represent an alternative, which are increasingly being used in clinical trials to correct deficiency. However, it is unclear whether sunshine exposure and vitamin D supplementation induce comparable changes in immune function, or whether additional UVR-induced molecules may be responsible for proposed health benefits. Several studies report an inverse correlation between exposure to UVR and immune-mediated diseases, further supporting the theory that UVR may also be protective through non vitamin-D mediated pathways. So far it has been difficult to distinguish between immune-regulation by vitamin D and other mediators induced by UVR as the downstream effects are similar. A direct comparison of the biological effects of vitamin D obtained by UVR versus supplementation has never been made. This study aims to elucidate the differences in vitamin D generated by UVR exposure versus supplementation by comparing immunological endpoints

Conditions

• Vitamin D Deficiency

Interventions

Type	Name	Description
DIETARY_SUPPLEMENT	Vitamin D	Daily 4X 1000IU cholecalciferol
RADIATION	UVR (Solar simulated radiation)	1.25 SED Solar simulated radiation twice weekly

Timeline

• Start date: 2015-11-19
• Primary completion: 2017-04-14
• Completion: 2017-04-14
• First posted: 2018-08-01
• Last updated: 2018-08-01