The Impact of Gluten on Haematological Status, Dietary Intakes of Haemopoietic Nutrients and Vitamin B12 and Folic Acid Absorption in Children with Coeliac Disease

Abstract

The haematological status, as well as the fractional absorptions of folic acid-and of vitamin B12 (FAFol and FAB12) were studied longitudinally in 20 coeliac children aged 1.2-16.6 yr (mean 7.5 yr) during periods of gluten-free and gluten containing diets. The absorption methods were specially adapted to use in children, and age-related reference limits were established . Also, dietary intakes of iron, folate and B12 were registered. The haemoglobin concentrations did not show any significant differences in relation to shifts in diet. A few had milk anaemia while the haemoglobin concentrations in the other patients remained within normal range. The iron status, as judged from mean corpuscular volume (MCV), serum (S)-iron, S-transferrin and saturation%, appeared to be generally insufficient. However, the only significant change related to shifts in diet was an increase of S-iron during the first period of gluten-free diet. Dietary intakes of iron proved to be insufficient, regardless of the type of diet. Plasma (P)-B12 concentrations demonstrated a wide range of values above the lower normal limit, whereas the level in a single patient was within the "intermediate range" of B12 insufficiency (150-200 pmol/l). The folate status (erythrocyte-folate) showed significant variations related to dietary changes. However, few patients were folate depleted. FAFol and FAB12 demonstrated rapidly occurring, and significant decreases and increases in relation to gluten challenge and gluten-free diet, respectively. Bacterial overgrowth of the small intestinal tract was not found to be a plausible cause of the B12 malabsorption in the case of 5 patients observed. In conclusion, it is recommended that the dietary management of coeliac patients with regard to haemopoietic nutrients focus on an appropriate iron intake. While a few patients failing to keep a strict gluten-free diet risk folate depletion due to malabsorption and to inadequate intake, these patients are, on the other hand, unlikely to develop vitamin B12 deficiency.