Summary: The mean serum 25-OH-D was 23.1 ng/mL in 49 female Japanese college students, and concentrations in 33% of them were ≤20 ng/mL. Subsequently, they consumed milk fortified with 2 μg of vitamin D daily for 8 weeks. Then, 25-OH-D increased to 36.0 ng/mL and all values were ≥20 ng/mL.
Purpose: Commercial milk in the USA is fortified with vitamin D (VD), whereas food fortified with VD is unpopular in Japan even though dietary sources of this vitamin are limited. Therefore, young Japanese females might be VD deficient. This study assesses the effects of ingesting milk fortified with VD among Japanese female college students.
Methods: Forty-nine female college students consumed 180 mL of milk fortified with 2 μg of VD daily for 8 weeks. This amount of VD in the milk was similar to that in commercial milk sold in the USA. Serum concentrations of 25-OH-D were measured in venous blood collected before and after the ingestion period.
Results: The initial serum 25-OH-D concentration was 23.1 ng/mL and concentrations in 33% of the participants were ≤20 ng/mL. After 8 weeks, serum 25-OH-D increased to 36.0 ng/mL and all values were ≥20 ng/mL. Serum Ca and FGF-23 also increased and PTH, NTX, and BAP significantly decreased.
Conclusions: The high prevalence of VD deficiency in Japanese female college students was decreased by consuming VD-fortified milk.