Dietary calcium intake in patients with inflammatory bowel disease

Abstract

Background & aims: Osteopenia and increased risk for fractures in IBD result from several factors.

Aim of the study: To investigate the dietary intake of calcium in IBD patients.

Methods: A 22-item quantitative validated frequency food questionnaire was used for quantifying dietary calcium in relation to gender and age, in 187 IBD patients, 420 normal- and 276 diseased controls.

Statistical analysis: Mann-Whitney, chi-square- and T-tests.

Results: The mean calcium intake was 991.0 ± 536.0 (105.8% Recommended Daily Allowances) and 867.6 ± 562.7 SD mg/day (93.8% RDA) in healthy and diseased controls, and 837.8 ± 482.0 SD mg/day (92.7% RDA) in IBD, P<0.001. Calcium intake was high in celiac disease (1165.7 ± 798.8 SD mg/day, 120% RDA), and non-significantly lower in ulcerative colitis than in Crohn's disease (798.7 ± 544.1 SD mg/day vs 881.9 ± 433.0). CD and UC females, but not males, had a mean calcium intake well under RDA. In all study groups the intake was lower in patients believing that consumption of lactose-containing food induced symptoms, versus those who did not (105.8% vs 114.3% RDA in normal controls; 100.4% vs 87.6% RDA in IBD).

Conclusions: Diet in IBD patients contained significantly less calcium than in healthy controls. Gender and age, more than diagnosis, are central in determining inadequate calcium intake, more so in IBD. Self-reported lactose intolerance, leading to dietary restrictions, is the single major determinant of low calcium intake. Inadequate calcium intake is present in one third of IBD patients and represents a reversible risk factor for osteoporosis, suggesting the need for tailored nutritional advice in IBD.

Keywords: Crohn's disease; Dietary calcium; IBD; Lactose intolerance; Osteoporosis; Ulcerative colitis.