A prospective longitudinal study published this year in the British Journal of Dermatology compared the differences in seasonal vitamin D levels between patients who are sensitive to the sun and healthy people.
Rhodes LE, Webb AR, Berry JL, et al. Sunlight exposure behaviour and vitamin D status in photosensitive patients: longitudinal comparative study with healthy individuals at UK latitude. Br J Dermatol. 2014; [Epub ahead of print]
The authors of the study wanted to know if people who are sensitive to the sun due to skin conditions like polymorphic light eruption, solar urticaria, or as a side effect from medications have lower vitamin D levels than people who don’t have these conditions. This population is frequently advised to avoid the sun and use sunscreen when they are outside.