- Getting enough vitamin D is crucial for your overall health.
- Many Americans are deficient in vitamin D, which can impact all kinds of things including our sleep.
- Although studies have found that poor sleep and low vitamin D levels are associated, researchers have yet to identify the root cause of this association.
- INSIDER spoke with two doctors and they told us about the connection between sleep and vitamin D, and why they’re more closely linked than you might realise.
With our increasingly hectic lifestyles, it can be challenging for many of us to prioritise getting enough sleep on a regular basis, even though quality sleep is intrinsically linked to our overall health and well-being.
INSIDER spoke with two doctors about the connection between sleep and vitamin D, and why they’re more closely linked than you might realise.
Vitamin D is largely linked to bone health but is also important for quality sleep
Los Angeles-based board-certified dermatologist Tsippora Shainhouse, MD, FAAD previously told INSIDER that “vitamin D is a fat-soluble vitamin that is responsible for calcium homeostasis and bone health … it increases the efficiency of calcium and phosphorus absorption from the small intestine and aids in the maturation of osteoclasts in the bone.”
Dr. Shainhouse added that “healthy levels of vitamin D have been demonstrated to prevent skin ageing, promote healthy bone growth, possibly reduce the risk of certain cancers, and even improve mood.”
Research shows a direct link between vitamin D levels and the quality and quantity of your sleep
“Vitamin D plays a number of important functions in the body, the most well known of which is that it interacts with calcium to promote strong, healthy bones,” said Dr. Greg Burrell, co-founder and VP of clinical product at Carbon Health. “However, it also helps regulate the immune system, and early studies suggest that it can help control inflammation in the body as well.”
Being deficient in vitamin D can lead to a host of sleep issues, including sleep disruption, insomnia, and overall poor sleep quality
“A deficiency in Vitamin D has been associated with many changes in sleep such as fewer sleeping hours, and sleep that is less restful and restorative,” said Dr. Burrell, adding that “it has also been linked with increased inflammation of the nose and tonsils, which can lead to sleep apnea and disturbed sleep.”
Robert Glatter, M.D., an assistant professor of emergency medicine at Lenox Hill Hospital, Northwell Health, confirms this link, telling us, “vitamin D deficiency is linked to sleep disorders including poor sleep quality, short sleep duration, and sleepiness. Results of a recent meta-analysis indicated that low [vitamin D] levels were associated with an increased risk of sleep disorders.”
“It may not only lead to insomnia but also sleep disruption and sleep apnea, especially if you’re already at higher risk for developing these disorders,” he told INSIDER.
There might be a link between vitamin D levels and our immune system, thus leading to sleep apnea
Sleep apnea is a disorder in which a person’s breathing becomes irregular while they sleep, due to miscommunication between the brain and the muscles of the nose and throat. Our experts indicated that low vitamin D levels might be linked to people with sleep apnea.
“Research also indicates that vitamin D may play an immunomodulatory role by impacting immune regulation, and decreasing the release of inflammatory substances which regulate sleep itself, such as prostaglandin D2, tumour necrosis factor alpha (TNF-a), and other cytokines,” said Dr. Glatter.”Additional studies indicate that patients with obstructive sleep apnea syndrome(OSAS) had lower levels of Vitamin D and higher levels of lipocalin-type PGD synthase than patients without OSAS.”But the exact reasoning behind this link is still being studied.
The relationship between vitamin D levels and sleep is still unclear, according to Dr. Burrell. He said, “There hasn’t been a clear link established with how a normal vitamin D level can help improve sleep. As of now, nearly all the studies that have been published are association studies, meaning that all we can observe is that people with lower vitamin D levels have a lower quality of sleep – however, these studies have not identified the root cause of this association.”
Dr. Glatter confirmed this, adding that “although the underlying mechanisms to explain the association between vitamin D deficiency (VDD) and sleep disorders are not yet known, the high distribution of vitamin D receptors throughout areas of the brain that regulate the sleep-wake cycle are evidence of this strong association. This is especially evident in the hypothalamus, prefrontal cortex, and substantia nigra, areas integral to the sleep-wake cycle.”
These issues can impact us during daytime hours, too
With research continually showing that just one night of poor sleep can impact both our bodies and our minds, chronic sleep deprivation or sleep issues can have serious consequences, according to Dr. Burrell.
“The effects can be wide-reaching – increased drowsiness and decreased productivity at work are the most prominent. A low quality of sleep also puts us at an increased risk for mental health illnesses, such as depression and anxiety.”
There are other troubling impacts, according to Dr. Glatter, who told INSIDER that “we may experience fatigue, poor concentration, along with memory loss. We can’t function optimally and productivity can suffer. Mood is also affected, with increased irritability and mood swings. Vitamin D supplementation is also linked with better moods and higher degrees of happiness. A study in 2014 demonstrated the positive effect of vitamin D3 on mood was clinically significant.”
Getting enough sleep can also help us better absorb vitamin D naturally
“Lack of sleep, as well as inconsistent sleep, may increase irritability, but also contribute to mood swings and poor judgment. Getting between 7 to 9 hours of sleep each night is the best way to ensure that your body can attain optimal levels of vitamin D,” said Dr. Glatter.”As the sun sets, the brain naturally converts serotonin into melatonin, a key sleep hormone,” he added. “Together with melatonin, vitamin D is integral in sleep induction.”
There are some lifestyle changes that might be making many of us deficient in vitamin D
Our modern lifestyles may be to blame for an increase in vitamin D deficiency of all ages, according to Dr. Glatter. “We are seeing more vitamin D deficiencies likely due to people spending more time indoors, but also using more sunscreen when spending time outside,” he said.”According to a 2012 Spanish study, 70% of [European] adults … don’t have sufficient levels of vitamin D,” he said, adding that “low levels of vitamin D have been associated with depression in adults, as well as mood variability and ADHD in children. Vitamin D supplementation is associated with better quality of life and well-being as we age.”
Americans are no better off – in fact, Dr. Burrell added that “most of the United States does not get strong enough sunlight during the winter months to boost vitamin D adequately. Additionally, as more people work in offices along with the increasing concerns surrounding sun damage to the skin, premature ageing and skin cancer, sun exposure is not always the right answer to boost vitamin D.”
While it might seem like the easy answer is to spend more time outdoors, the risk for sun damage and skin cancer is high no matter what the temperatures are like outside. You need to wear sunscreen and sun protective clothing if you’re going to be outdoors for any extended length of time.
Low vitamin D levels can have different sleep impacts based on your age, where you live, or even the current season
There are many variables when it comes to our vitamin D levels, including age, location, and the time of year.
“As we age, we are more sensitive to the effects of lower levels of vitamin D,” shared Dr. Glatter. “Older persons are more likely to experience poor sleep quality and duration as vitamin D levels decline. As the levels are restored, they tend to show marked and rapid improvements in sleep quality and duration.”
Dr. Burrell adds that “problems brought on by poor sleep manifest in different ways – for example, in younger people, this may manifest as decreased productivity, more colds or viral illnesses, etc. Among older patients, the effects would be decreased cognitive ability, confusion, and other symptoms.”
“Levels of vitamin D are typically lower during the wintertime in people who live in the northern hemisphere,” said Dr. Glatter, which “may have a negative impact on sleep duration and quality, and is associated with elevated blood pressure, and increased risk of strokes and heart attacks during [cooler months],” with Dr. Burrell confirming that “since vitamin D can fluctuate based on sun exposure, it can also fluctuate based on seasons and impact sleep as a result.”
Testing your vitamin D levels is easy as is boosting them
Both our experts told us that your doctor can give you a blood test to determine your vitamin D levels, with Dr. Glatter adding that “if you are experiencing excessive fatigue, it would be ideal to check not only a TSH level, but also your vitamin D level.”
Excessive sun exposure can do more harm than good, but there are several other ways to ensure you’re getting enough vitamin D and help increase your chances of a restorative night’s sleep.
According to Dr. Glatter, “Fortified milk, eggs, mushrooms, salmon, tuna, mackerel and dairy products are good sources of Vitamin D. In fact, a 4-ounce portion of salmon can provide over 250% of your daily recommended allowance (RDA) of vitamin D. Wild salmon contains much higher levels of Vitamin D than farmed salmon – 988 IU of vitamin D per serving, while farmed salmon contains about 250 IU.”
He added, “It’s best to get 10-30 minutes a day of direct sunlight in order to boost vitamin D3 levels. A specialised ‘light box’ may be helpful if you live in an area of the country where there is inadequate daylight or sun exposure. A box that is close to the natural spectrum of sunlight is recommended.”
There are also over-the-counter vitamin D supplements, which your doctor can help recommend.
Overall, getting more vitamin D can help improve sleep
“In general, the quality of your sleep will improve as your vitamin D level rises, so that you not only sleep longer, but also experience more restful sleep,” said Dr. Glatter. “You may find yourself falling asleep easier, and being able to stay asleep, without experiencing interrupted sleep.” If you’re concerned, check with your doctor, who can provide the best treatment options for you and your body.
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