date:Dec 24, 2012
, higher levels of daytime sleepiness were associated with lower levels of vitamin D.
The researchers found excessive daytime sleepiness was directly correlated with 25OHD in black patients with vitamin D deficiency, but not Caucasian patients with vitamin D deficiency. The higher the vitamin D levels they had, the more likely they were to have daytime sleepiness, showing the vitamin/sleep relationship is complex.