If you’re falling asleep at your desk, skip the latte and go get your vitamin D levels checked. There is new research suggesting a significant correlation between excessive daytime sleepiness and vitamin D deficiency, and race plays an important factor.
It is well known that vitamin D is a primary regulator of calcium and phosphorous, helping to protect bone density. However, more recently scientists have been able to determine exactly how vitamin D functions in the body. We now know that vitamin D plays an important role in metabolic and immune function. Vitamin D deficiency has been linked to many illnesses and chronic conditions, including stress, high blood pressure, diabetes, metabolic syndrome, pulmonary disease and chronic pain.
Previous research provided evidence that a lack of vitamin D is associated with sleep issues. This new study examined the link specifically between daytime sleepiness and vitamin D deficiency, and also considered one of the major risk factors of that deficiency: skin pigmentation.
Researchers at Louisiana State University investigated the relationship between vitamin D and daytime sleepiness with two specific goals in mind. First, they wanted to determine whether a correlation exists between vitamin D levels in the body and excessive daytime sleepiness. Second, they wanted to evaluate the role that race might play in the relationship between daytime sleepiness and vitamin D.
The LSU study, published in the Journal of Clinical Sleep Medicine, involved a consecutive series of 81 sleep clinic patients who complained of sleep problems and nonspecific pain. All patients eventually were diagnosed with a sleep disorder, which in the majority of cases was obstructive sleep apnea. Vitamin D level was measured by blood sampling, and sleepiness was determined using the Epworth Sleepiness Scale.
The results of the study support a strong correlation between excessive daytime sleepiness and vitamin D. They also indicate that race is a factor in the relationship between vitamin D and daytime sleepiness. But that relationship is complicated, with the study yielding unexpected results. In patients with normal vitamin D levels, progressively higher levels of daytime sleepiness were correlated inversely with progressively lower levels of vitamin D. Among patients with vitamin D deficiency, sleepiness and vitamin D levels were associated only among African-American patients. Surprisingly, this correlation was observed in a direct relationship, with higher vitamin D levels associated with a higher level of sleepiness among African American patients, exactly the opposite of what was expected.
Clearly, additional research is needed. Based on the association between vitamin D deficiency and daytime sleepiness, we are left with further questions. Is vitamin D deficiency directly responsible for excessive daytime sleepiness and other sleep problems? Or is poor sleep a consequence of other medical conditions associated with vitamin D deficiency, such as stress? Scientists are now looking further into the causes of vitamin D deficiency and its relationship with sleepiness.
One thing is for certain: if you are feeling tired and sluggish during the day, don’t assume you need another cup of coffee. Talk to your doctor. It is quite possible that you are deficient in vitamin D. Supplements, dietary changes, and safe and controlled exposure to sun can all help boost levels in the body. Making sure your body has sufficient levels of vitamin D has important health implications and you just might find yourself with a boost of daytime energy!