A study appearing in Photodermatology, Photoimmunology and Photomedicine (2008; 24(5): 260-7) found that patients with cutaneous lupus erythematosus (CLE) tended to be deficient in vitamin D, possibly because of restriction to sun exposure. Low vitamin D levels were found in 65% of the 52 patients involved in the study. Another study appearing in the American Journal of Medical Science (2008; 335(2): 99-104) looked at 37 female patients with systemic lupus erythematosus (SLE). The study found that lower vitamin D status was associated with higher disease activity.