Half of US high school students will have dark skins by 2025
American Higher Education Hits a Dangerous Milestone The Atlantic - May 2018

See also VitaminDWiki
Striking ethnic health disparity – blacks dying due to lack of vitamin D – Nov 2011
Preterm birth more likely if dark skinned and low vitamin D (not white-skinned) – April 2017
Dark skin pregnancies 2.6 times more likely to have low vitamin D – March 2017
5,000 IU daily or 50,000 IU Vitamin D weekly repleted many dark skinned adolescents – RCT Dec 2015
Items in both categories Skin - Dark and Youth are listed here:
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