Vitamin D deficiency is an epidemic, with more than 50% of humans worldwide deficient in Vitamin D. Because of the critical, unique role Vitamin D plays in the regulation and maintenance of sleep-wake cycles and restorative sleep, many sleep specialists believe the worldwide sleep deprivation and insomnia epidemic is caused by - or, greatly exacerbated by - Vitamin D deficiency.
Vitamin D is a critical component to health and wellness. Many Americans supplement Vitamin D for bone health and immune system functions. However, the role of Vitamin D in regulating and improving sleep quality is equally critical. The relationship between Vitamin D and sleep is intuitively known to most people. Of the many common symptoms of Vitamin D deficiency, the three most well-recognized are insomnia, fatigue, and depression. Prolonged periods of darkness in the winter months are associated with mood swings (or ‘seasonal-affective disorder’), reduced energy, and poor sleep. An average five to seven pound weight gain is common in the winter, attributed to more than just binging on holiday sweets. When increased sunlight comes with spring and summer, periods of extended cloud cover or storms can temporarily disrupt sleep patterns, as often seen with the sleep disruption and increased stroke risk during Daylight Savings Time.
Dietary Vitamin D sources include fatty fish (such as salmon), egg yolks, and fortified dairy and juices. A variety of supplements are also available. However, the best source of Vitamin D comes from the sun, which in the context of sleep regulation offers a dual effect.
For thousands of years, humans lived in direct sunlight for 8-10 or more hours daily, initially as hunter-gatherers and then as our societies shifted to agrarian cultures with farming. The industrial revolution shifted a portion of the human workforce from the outdoor fields to the indoor factories. However, diets still largely consisted of consumption of animal fats (containing dietary cholesterol used in Vitamin D synthesis), and human activity levels remained high with physically-demanding jobs. The presence of persistent artificial light and entertainment options coupled with heavy labor (often lasting far in excess of 6-8 hour work shifts without breaks or rest periods) allowed humans to maintain sleep-wake cycles despite the reduction of sunlight exposure.
The beginning of the twenty-first century, however, represented a convergence of several factors that contribute to Vitamin D deficiency and poor sleep:
- Little or no exposure to direct sunlight due to indoor workforce;
- Reduced physical demand and activity levels at work due to “office-style work;”
- De-emphasis on dietary fats and dietary cholesterol in favor of plant unsaturated fats and reduced cholesterol;
- Increase in artificial light exposure after sunset;
- Increase in ‘blue light’ emitting devices, including smart phones, tablets, and computers/laptops;
- Increase in mentally-engaging forms of entertainment and stimulation; and
- Increase of work and work-related activities in the bedroom environment.
These cultural and environmental factors dramatically reduce bioavailable Vitamin D as well as the effectiveness of sleep hygiene, thus exacerbating insomnia and reducing total night restorative sleep.
- Fatigue and weakness
- Difficulty with concentrating, focusing, or remembering things
- Soreness, pain, or fractures of bones
To improve the quality of your restorative sleep, natural Vitamin D synthesized from exposure to sunlight is optimal, as daily sunlight helps your body to regulate your circadian rhythm. Taking long walks outdoors (particularly during sunrise in the morning and prior to sunset in the evening) help to activate your brain’s natural production of neurotransmitters responsible for regulating your body’s internal clock and also producing a sense of peace and well-being. Walking also is good for health, and if done in a relaxing environment such as out in nature, can reduce stress and improve cardiovascular and mental health.
In Austin, TX, where SleepSomatics sleep disorders testing and treatment center is located, we are very fortunate to have an array of options for exercise and sunlight exposure. But you don't have to hike Mount Bonnell or walk the entire Lady Bird Lake Trail to begin gaining the benefits of Vitamin D for sleep regulation. Insomnia, fatigue, and depression are as much biochemical states as they are states of mind. Humans have evolved outdoors and in the sun, surrounded by the vast, verdant beauties of our planet. In Japan, for example, there are 'forest bathers' who hike into the forests for meditative therapy in nature. And though this may sound silly to many people, we all have experienced the emotional 'rebound' effect that comes when spending a Saturday outdoors - whether sporting on Lake Travis, camping in Hill Country, or even visiting a local park.
There are quantifiable neurological and hormonal benefits to increasing our exposure to the clean outdoor lifestyle and reconnecting with natural elements, and as we have discussed in this article, science has confirmed how this outdoors exposure can increase Vitamin D production and regulate our nightly restorative sleep cycles.
Try taking a daily walk (or two) and increase your body’s exposure to the sun and to nature for increased wellness, health, and more restorative, full night sleep.
If you have difficulty sleeping or are suffering from insomnia, getting help is as easy as scheduling a New Patient Sleep Assessment at SleepSomatics, Austin's top-rated sleep disorders testing and treatment clinic and sleep lab. Restore your life with restorative sleep today.