Narrowband ultraviolet B therapy is an effective means of raising serum vitamin D levels

Conflict of interest: none declared. Despite the fact that Australia has a reputation as a land of sunshine, studies have found that vitamin D deficiency is common in the normal Australian population, even in the subtropical region of the continent.1, 2 Deficiency is usually corrected by large doses of cholecalciferol. Patients are given 300,000–500,000 IU of cholecalciferol over 1–10 weeks, and this has been shown to be a safe, effective way of replenishing vitamin D stores.3 As ultraviolet (UV) light therapy is now generally given as narrowband UVB (nUVB) therapy rather than broadband UVB, we aimed to determine if nUVB therapy could correct vitamin D deficiency as effectively as high doses of cholecalciferol. The study was carried out during the winter of 2006 in Melbourne, Australia, which is located at 37° south. The study population was divided into two groups. The two groups were not closely matched because the aim of this small pilot study was to see if nUVB could raise serum 25‐hydroxy vitamin D (25‐OHD) and to evaluate its efficacy compared with vitamin D supplements. The UVB group comprised outpatients (seven men) with extensive psoriasis or dermatitis requiring nUVB therapy to clear the condition, and the cholecalciferol group comprised people (five men, two women) with pronounced vitamin D deficiency as assessed by the 25‐OHD level. This group were either outpatients with skin diseases that did not need UVB therapy or doctors working in the outpatient department.