Wake Up Refreshed: Uncovering The Connection Between Vitamin D and Sleep

If you're having sleep problems, you may be missing the essential "sunshine vitamin". New research shows a strong link between low levels of vitamin D poor sleep. While most people associate vitamin with bone health, and in some cases immune function, this functional nutrient is also responsible for regulating the body's natural sleep-wake cycle and producing melatonin, which are crucial for getting a good night's sleep. If you're having trouble falling asleep or staying asleep, or just not getting the sleep you want--could vitamin D be the perfect natural sleep aid? 

For the 41% of U.S. adults who are insufficient in vitamin D, and the 29% who are genuinely deficient, anyone looking to improve sleep quality would be smart to start by checking their vitamin D status (1).

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Low vitamin D levels linked with shorter sleep duration, poor quality sleep

Growing evidence links vitamin D with sleep regulation. Vitamin D deficiency can increase risk of sleep disturbances and is associated with shorter sleep duration and nighttime awakenings in children and adults (2).

Other sleep disorders, such as obstructive sleep apnea, have also been associated with lower vitamin D levels.

The average adult needs at least 7 hours of sleep per night.Less than that, and important cognitive and metabolic processes likely aren’t functioning optimally. Coincidentally, one analysis revealed that those who get less than 7 hours have an average daily intake of approximately 178 IU of vitamin D (3). 

That's less than 10% of what's needed to avoid a frank deficiency, and an alarming 3.5% of the necessary daily dosage to achieve more optimal vitamin D levels, which research suggests is a blood level of about 50-60 ng/mL.

Currently, 2,000 IU will prevent an outright deficiency (<20 ng/mL), but this is barely enough for essential bodily functions. A more optimal intake of vitamin D would be about 5,000 IUs daily.

Are you getting the vitamin D you need? Find out.

How vitamin D impacts sleep

As far as sleep quality is concerned, vitamin D functions more like a hormone than a vitamin. To promote healthy sleep, vitamin D acts as a messenger in different areas of the brain, as well as activating various enzymes to promote sleep.

Vitamin D receptors are found in multiple areas of the brain that regulate sleep, including the hypothalamus, suggesting multiple functions along the pathway to quality sleep (2). 

Vitamin D has also been found to have a direct impact on melatonin production, the hormone responsible for encouraging sleep. Vitamin D deficiency has been linked to reduced melatonin levels in both adults and children, which can make it especially hard to fall asleep.

Another theory involves the effect of sunlight. It is well known that vitamin D levels are regulated by exposure to sunlight and since sunlight also affects the circadian rhythm, there's likely a link between those factors.

Low vitamin D in children and adolescents

Low vitamin D levels can have particularly detrimental effects on children and adolescents, who require adequate sleep for growth and development. Vitamin D supplementation in teens has been found to improve quality of sleep, as well as to reduce daytime fatigue (4).

Vitamin D receptors can also be found in the brain (in the hippocampus, amygdala, and prefrontal cortex) suggesting that vitamin D is also associated with the regulation of mood and emotional behavior in children & teens (5). 

Since the brain regulates sleep and sleep quality and sleep cycles. With children, vitamin D is very important since it impacts brain development and neuronal growth factors.