Vitamin D plays an important role in your immune system function and metabolic functions. If you have a deficiency in vitamin D, it can lead to serious health conditions like chronic pain, pulmonary disease, metabolic syndrome, diabetes and high blood pressure.

But what about sleep? How does a deficiency in vitamin D affect a good night’s rest? Could you improve your sleep by drinking or eating  more foods fortified with vitamin D or by popping a supplement?

Vitamin D and Daytime Sleepiness

There appears to be a correlation between insufficient vitamin D levels and daytime sleepiness. Researchers from Louisiana State University were part of an investigation involving 81 patients. All the patients experienced either musculoskeletal pain or sleep problems at some point during the day or evening. All also had a sleep disorder, such as restless leg syndrome, insomnia and obstructive sleep disorder.

As part of their evaluation, the patients were also assessed for excessive daytime sleepiness, and blood tests were used to measure their vitamin D Levels. The study showed:

• • Vitamin D deficiency in 65 percent of the participants
  • Direct correlation between vitamin D deficiency and daytime sleepiness

(Surprisingly, higher levels of vitamin D in African-American participants were linked to daytime sleepiness. As it applies to African-Americans and not other participants in the study, there appears to be a correlation opposite to that hypothesized by researchers.)

Vitamin D and Other Sleep Conditions

Other sleep disorders, such as obstructive sleep apnea and additional sleep issues, appear to be related to vitamin D or natural light exposure.

There are studies that support the need for sufficient levels of vitamin D. For patients with obstructive sleep apnea, continuous positive airway pressure (CPAP) treatment appears to increase vitamin D levels in men.

In yet another study, those with sleep and depressive symptoms may find a lack of natural light within their workspace to be a contributor.

Much needs to be learned about the relationship between vitamin D and sleep, but findings underscore its importance to getting a restful night’s sleep. It can also be a key factor that affects individuals experiencing insomnia and other sleep disorders.

How to Increase Levels of Vitamin D

There are several ways to increase your vitamin D levels.

Exposure to sunlight and important ultraviolet B rays can increase your body’s vitamin D levels. But catching enough rays to affect your vitamin D levels can be dependent on your skin color, the amount of exposed skin, your location and the time of the day.

Supplementation may be necessary in northern areas, like Chicago or Boston, as it is difficult to get enough sunlight exposure to produce the amount of vitamin D that you need in the winter months .

A good way to increase your levels of vitamin D are to drink milk or eat cereal fortified with vitamin D. Coincidentally, many people drink warm milk when they have trouble sleeping. Those with insomnia or a sleep disorder may want to get a blood test to determine if they are experiencing lower than normal vitamin D levels.

By taking supplements or increasing your exposure to natural light, you can elevate your vitamin D levels and make it easier to experience a restful night’s sleep.