African-Americans with poor sleep have lower levels of vitamin D – Aug 2015

Vitamin D and improved sleep in African-Americans Clinical Advisor

• “Polysomnography and actigraphy demonstrated that participants with vitamin D deficiencies had shorter sleeper duration, less REM sleep, and higher scores on the Epworth Sleepiness Scale. In African-Americans, low vitamin D levels were significantly associated with shorter average sleep duration. There was no association between vitamin D levels and sleep duration with other races and ethnicities. Why the difference between races? While the answer is unclear, it may be due to differences in metabolism, receptor activity, and activation of vitamin D.”

Reporting on 25-Hydroxyvitamin D Concentration and Sleep Duration and Continuity: Multi-Ethnic Study of Atherosclerosis Sleep Journal

Publisher wants $8 for the PDF

• “. . . ‘African Americans, in whom adjusted sleep duration was 25.6 ± 11.7 min shorter in deficient versus sufficient individuals”

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Note: this study did not appear to have other than African-Americans with dark skins.
The conclusion that Africa-Americans sleep less if they have low vitamin D
should perhaps be that Dark-Skinned individuals with low vitamin D sleep less

See also VitaminDWiki

• Sleep longer if have more vitamin D – many studies
• Sleep disorders cured by 60-80 ng of vitamin D and some B vitamins – March 2013

Items in both categories Sleep and Skin-dark are listed here: