Bread fortified with cholecalciferol increases the serum 25-hydroxyvitamin D concentration in women as effectively as a cholecalciferol supplement

Fortification of foods is a feasible way of preventing low vitamin D status. Bread could be a suitable vehicle for fortification because it is a common part of diets worldwide. The bioavailability of cholecalciferol from bread is not known. We studied cholecalciferol stability, the concentration of the added cholecalciferol, the dispersion of cholecalciferol in bread, and the bioavailability of cholecalciferol from fortified bread.

Three batches of fortified low-fiber wheat and high-fiber rye breads were baked; from each batch, 3 samples of dough and bread were analyzed for their cholecalciferol content. In a single-blind bioavailability study, 41 healthy women, 25-45 y old, with mean serum 25-hydroxyvitamin D concentration 29 nmol/L (range 12-45 nmol/L), were randomly assigned to 4 study groups.

Each group consumed fortified wheat bread, fortified rye bread, regular wheat bread (control), or regular wheat bread and a cholecalciferol supplement (vitamin D control) daily for 3 wk. The daily dose of vitamin D was 10 mu g in all groups except the control group. The vitamin dispersed evenly in the breads and was stable.

Both fortified breads increased serum 25-hydroxyvitamin D concentration as effectively as the cholecalciferol supplement. Supplementation or fortification did not affect serum intact parathyrold hormone concentration or urinary calcium excretion. In conclusion, fortified bread is a safe and feasible way to improve vitamin D nutrition.