Early-life vitamin D deficiency and childhood-onset coeliac disease.

Many studies have investigated the aetiological roles of genetic and environmental factors in coeliac disease (CD) with the long-term goal of developing an effective primary prevention strategy. CD is a condition with dysregulated systemic and intestinal mucosal immune responses to dietary gluten proteins among genetically predisposed individuals. We recently described spring birth as a novel risk factor for CD in children. We believe that the association between season of birth and CD is due to seasonal differences in sunlight exposure and subsequent vitamin D status. Concomitant with global increases in CD prevalence, vitamin D deficiency also is increasingly recognized in children worldwide. Recent studies have shown that vitamin D deficiency can cause improper immune responses, abnormal intestinal mucosal integrity and impaired local defence to pathogenic microbial agents. In conjunction with other potential aetiological factors, we propose a hypothesis model of early-life vitamin D deficiency in the pathogenesis of childhood-onset CD.