Vitamin D Deficiency and Poor Sleep

Britain is in the Warm Gulfstream, which makes it mainly cloudy and starves us of sunshine much of the year. Sunshine is the best source of Vitamin D, so all that gloomy, grey weather can make you Vitamin D deficient.

This wouldn't be an enormous problem if not for the fact that Vitamin D has a significant role in sleep regulation. Studies show that being low on Vitamin D increases sleep disorder risks and awakenings in children and adults.

The bottom line - if you have sleep problems, you might have a Vitamin D deficiency.

The National Diet and Nutrition Survey shows that 1 in 6 adults in the UK have low levels of Vitamin D, so the problem is prevalent in society.

This article uncovers the link between Vitamin D deficiency and poor sleep, with links to studies and research for further reading.

Let's jump in!

The relationship between Vitamin D and sleep

A 2018 meta-analysis of Vitamin D and sleep studies found that Vitamin D deficiency is associated with a higher risk of sleep disorders like insomnia.

A more recent 2022 scientific report reveals a bi-directional relationship between low Vitamin D levels and poor sleep, suggesting that poor sleep exasperates deficiencies and low Vitamin D worsens sleep problems.

It is clear from studies and clinical research that Vitamin D and poor sleep are linked, but the precise reason why is a contentious matter.

Why does Vitamin D deficiency impact sleep?

Vitamin D isn't technically a vitamin – it's a hormone. It has several bodily functions, such as helping you absorb calcium, but in terms of sleep, it activates serotonin synthesis, the happy hormone precursor to melatonin.

Serotonin is a mood-stabilising hormone that helps regulate your sleep-wake cycle by promoting wakefulness. Serotonin levels inhibit REM sleep, your body needs it to produce melatonin, the sleep hormone.

Melatonin regulates your sleep-wake cycle, with your body releasing more during the evening or when your body thinks it's time for sleep.

There is also a link between Vitamin D levels and anxiety and mood. Clinical studies have found Vitamin D can improve anxiety symptoms. While more studies are needed, the results are promising across clinical research.

According to statistics, 8 in 100 people have mixed anxiety and depression, and 6 in 10 have a generalised anxiety disorder. While Vitamin D isn't a golden solution to the problem, a deficiency could exasperate anxiety symptoms.

How to boost your Vitamin D intake

Firstly, you should identify a deficiency before boosting your intake.

Your GP can run blood tests to identify vitamin and mineral deficiencies, helping you identify possible reasons behind sleep problems.

If you do have a deficiency, the good news is it's easy to treat.

We get most of our Vitamin D from the sun, so the best way to get a boost is by heading outside when the sun is shining. Aim to get 10–30 minutes of midday sunlight and enjoy the heat as it warms you from top to bottom.

When the sun isn't shining, your best bet is foods high in Vitamin D, like eggs, fortified spreads, and drinks. The following foods are high in Vitamin D:

• Eggs
• Oily fish
• Red meat
• Liver
• Tuna
• Fortified foods and drinks

Another option is supplements – Vitamin D supplements contain either Vitamin D2 or D3, with D3 being superior for raising blood level concentrations.

Vitamin D is a safe supplement in appropriate dosages. We recommend following the NHS guidelines, which say children from the age of 1 year and adults need 10 micrograms of vitamin D daily.

Pay attention to dosages, don't take Vitamin D supplements alongside multivitamins, as this will take you over the recommended daily intake.

If you enjoyed this article, discover 

• 8 ways to sleep better naturally at night.
• Seasonal Affective Disorder: A Definitive Guide to SAD and How to Deal With It.