A new research has suggested that there may be a link between excessive daytime sleepiness and vitamin D.
The study demonstrates among those with normal vitamin D levels, lesser the Vitamin-D, higher was the occurrence of day-time sleepiness. And those with vitamin D deficiency, an association was observed among black patients. Surprisingly, higher vitamin D levels were associated with a higher level of sleepiness in black patients.
“While we found a significant correlation between vitamin D and sleepiness, the relationship appears to be more complex than we had originally thought,” said David McCarty, MD, the study’s principal investigator. “It’s important to now do a follow-up study and look deeper into this correlation.”
The study, appearing online in the Dec. 15 issue of the Journal of Clinical Sleep Medicine, is the first study to demonstrate a significant relationship between sleepiness and vitamin D. The researchers noted that it is logical for race to affect this relationship because increased skin pigmentation [dark skin] is an known to be a factor in lower vitamin-D.
The study was not meant to examine causality. However, the authors’ earlier and current research indicates that suboptimal levels of vitamin D may cause or contribute to excessive daytime sleepiness, either directly or by causing chronic pain.