![Schwartz JB et al. 2016; Response of vitamin D concentration to vitamin D3 administration in older adults without sun exposure: A randomized double-blind trial; J. Am. Geriatr. Soc. 64(1):65-72 - HEYL Schwartz JB et al. 2016; Response of vitamin D concentration to vitamin D3 administration in older adults without sun exposure: A randomized double-blind trial; J. Am. Geriatr. Soc. 64(1):65-72 - HEYL](https://www.heyl-berlin.de/img_upload/Vit-d-04034-625x405.jpg)
Schwartz JB et al. 2016; Response of vitamin D concentration to vitamin D3 administration in older adults without sun exposure: A randomized double-blind trial; J. Am. Geriatr. Soc. 64(1):65-72 - HEYL
How to read my vitamin D results in my blood test results? Also, is vitamin D 3000-4000 units a day safe for older adults that are in heart medication and other meds -
![Nutrients | Free Full-Text | Changes in Vitamin D Status in Korean Adults during the COVID-19 Pandemic Nutrients | Free Full-Text | Changes in Vitamin D Status in Korean Adults during the COVID-19 Pandemic](https://www.mdpi.com/nutrients/nutrients-14-04863/article_deploy/html/images/nutrients-14-04863-g001.png)
Nutrients | Free Full-Text | Changes in Vitamin D Status in Korean Adults during the COVID-19 Pandemic
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