Dietary vitamin D intake in patients with Crohn's disease.

In search for the reasons of vitamin D deficiency in Crohn's disease (CD), dietary records were evaluated over 7 days in 30 uninformed out-patients with CD (but no current flare-up) by the help of food tables and compared with those of 30 age- and sex-matched healthy controls. The study was undertaken in December. The nutritional status (height-weight index) was similar in both groups. The dietary vitamin D intake was as low in patient with CD (1.0 microgram/d; 0.5-1.3) as in the controls (1.1; 0.4-1.6) whereas the recommended daily intake is 5 micrograms/d. Vitamin D intake correlated with serum 25-hydroxyvitamin D (25-OHD) levels in patients with low 25-OHD levels (tau = 0.45, p = 0.04). Bone mineral content (BMC)-measured by single photon absorptiometry on the radius- was decreased in 9 patients (31%) with CD. Patients with CD tended to have a lower sun exposure in summer (p = 0.10), which also correlated with BMC (p = 0.03). Hence, a specific diet with a high vitamin D content, or vitamin D supplementation is recommended in patients with CD to overcome the negative effects of low sun exposure on bone mineral density.