Sunlight exposure or vitamin D supplementation for vitamin D-deficient non-western immigrants: a randomized clinical trial

Summary: Vitamin D deficiency is very common in non-western immigrants. In this randomized clinical trial, vitamin D 800 IU/day or 100,000 IU/3 months were compared with advised sunlight exposure. Vitamin D supplementation was more effective than advised sunlight exposure in improving vitamin D status and lowering parathyroid hormone levels. Introduction: Vitamin D deficiency (25-hydroxyvitamin D [25(OH)D]<25 nmol/l) is common among non-western immigrants. It can be treated with vitamin D supplementation or sunlight exposure. Methods: To determine whether the effect of vitamin D