Vitamin D deficiency is a condition that affects over 1 billion people worldwide, due to chronic disease, dietary deficiencies, use of sunscreen, and malabsorption. You may have heard of vitamin D, as the sunshine vitamin, as your skin makes vitamin D from sunlight exposure.
You may also know that vitamin D is crucial for bone health. However, it has many other essential roles in the body, including its effects on your sleep. In this article, I will explore the functions of vitamin D and its potential impact on your sleep so that you can get good quality sleep just after lights out.
Vitamin D has many processes in the body and in its active form, calcitriol, works as a hormone, regulating calcium and phosphorus levels and impacting the immune system
What’s the connection between sleep and vitamin D?
Vitamin D has many processes in the body and in its active form, calcitriol, works as a hormone, regulating calcium and phosphorus levels and impacting the immune system. Studies suggest that low levels of vitamin D are associated with decreased sleep time, reduced sleep efficiency, and increased daytime sleepiness. In one uncontrolled study, participants who raised their vitamin D levels saw significant sleep quality improvements.
Research into vitamin D and the sleep connection are still in their infancy, but it appears that vitamin D may affect sleep efficiency. Sleep efficiency relates the percentage of time you sleep out of the total time in bed. A study found that those with lower levels of vitamin D had less sleep efficiency. It’s never fun getting out of bed in the morning when you have been lying there for hours awake!
How does vitamin D impact sleep?
Theories suggest that vitamin D affects shut-eye by interacting with a part of the brain responsible for sleep. Put simply, there are vitamin D receptors in parts of the brain that are critical for sleep, and they require vitamin D to work properly. Think of these receptors as the locks to turn on sleep. Vitamin D is the key which turns on the receptors to do their jobs. In the absence of vitamin D, the receptors stay unlocked, so sleep is not initiated, and you remain wideawake regardless of bedtime.
Another possibility is that better sleep may also result from vitamin D’s influence on the immune system and its harmonising act on inflammation, leading to more valuable sleep.
There are vitamin D receptors in parts of the brain that are critical for sleep, and they require vitamin D to work properly
How much vitamin D do you need for better sleep?
Optimum levels of vitamin D ranges from 40 to 100 ng/mL. You can ask your doctor to test your levels or buy a private test online. If your levels are in this range, you should be all set for those forty winks! Remember, vitamin D is only one factor in the sleeping process. You need to consider your external stressors, sleep hygiene, and other sleep-promoting nutrients to immerse yourself in sleep fully. If your vitamin D levels are sub-optimal, then finding ways to up level might be a great way to start improving your sleep today!
How to naturally increase vitamin D levels
As the mightiest vitamin D source is from the sunlight – when the rays touch your skin, and cleverly your body converts it to active vitamin D – having some sun exposure daily, helps maintain healthy vitamin D levels.
The best vitamin D food sources are fatty fish such as mackerel, salmon, tuna, and sardines as vitamin D3. There are smaller amounts of vitamin D found in beef, pork, chicken, cheese, and egg yolks. Vitamin D2 is in plant sources such as mushrooms. Still, vitamin D2 is excreted from your body quickly, so if relying on plant-based vitamin D2, a daily supply is best as it does not store in your body like vitamin D3.
Vitamin D isn’t the panacea of optimal sleep, but it may be the missing piece of the jigsaw puzzle which once found, will help you drop into that restorative, restful sleep that leaves you feeling refreshed and bright-eyed and bushy-tailed when you wake!
Gao Q, Kou T, Zhuang B, Ren Y, Dong X, Wang Q. The Association between Vitamin D Deficiency and Sleep Disorders: A Systematic Review and Meta-Analysis. Nutrients. 2018;10(10):1395. Published 2018 Oct 1. doi:10.3390/nu10101395
Victoria Hamilton – Nutritionist BSc. Victoria is one of our Thrive Experts in Nutrition and holds a BSc in nutrition from Institute of Optimum Nutrition and has a BSc in Biochemistry with Immunology.