research Serum 25 Hydroxyvitamin D in Non-Scarring Alopecia: A Systematic Review and Meta-Analysis November 2023 in “Journal of Cosmetic Dermatology” People with non-scarring hair loss often have lower vitamin D levels than those without hair loss.
research Relationship Between the Level of Vitamin D in Blood Flow and Skin Dermatosis July 2021 in “Rossiiskii Zhurnal Kozhnykh i Venericheskikh Boleznei” Low vitamin D levels are linked to more skin problems.