Bone mineral density and importance of strict gluten-free diet in children and adolescents with celiac disease.

Objectives: Low bone mineral density (BMD) is common in children and adolescents with celiac disease. Strict gluten-free diet (GFD) improves bone mineralization, even in 1 year. The effect of occasional gluten intake is not known. The aims of this study were to compare BMD and prevalence of low BMD in children and adolescents on strict and not strict GFD.

Methods: We measured BMD in 55 children and adolescents (strict GFD) with negative endomysium antibodies (EMA) in the last 2 years and in 19 (not strict GFD) with positive EMA at the time of the study. Lumbar, left hip and total body BMD were measured by dual-energy X-ray absorptiometry. Four-day weighted dietary protocols were obtained by means of a self-completed questionnaire of total food and beverage intake. Energy and calcium intake were calculated using nutrition data software. EMA, tissue transglutaminase antibodies, serum calcium, phosphate, 25-hydroxy vitamin D, intact parathormone, albumin, urea and creatinine levels were determined in all patients.

Results: BMD in patients on strict GFD was significantly higher than in patients on not strict GFD (lumbar p=0.01; total body p=0.005). There were significantly more patients with total body BMD below -1.0 in not strictly compliant group (71% compared to 38%; p=0.03). Calcium intake and vitamin D levels were below recommendations in both groups.

Conclusion: Children and adolescents on not strict GFD are at increased risk for low BMD. We therefore recommend that BMD should be evaluated in patients with positive EMA. In addition, patients on strict GFD are at risk for low BMD because of low calcium intake or vitamin D deficiency. Therefore, strict GFD with recommended calcium intake and vitamin D supplementation during winter and spring should be encouraged in all children and adolescents with celiac disease.