[Nutritional aspects of vitamin D]
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Updated: Aug 7, 2026

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Published on: December 9, 2015
1Kyoto Women's University, Department of Food and Nutrition.
Abstract:
Dietary reference intakes for Japanese, 2005 defines the adequate intake (AI) for vitamin D to be 5 microg (200 IU), which is higher than the previously defined value of 100 IU. The difference reflects that vitamin D insufficiency has come to be taken into account in addition to vitamin D deficiency. Some questions, however, still remains to be answered, such as whether these values, far lower than those in USA or UK, is adequate or whether AI for the elderly should be separately defined.
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