Nutritional deficiencies can impact sleep (SQ-149)
A sleepless night or two is not a big concern. But if catching a good night’s sleep is becoming a daily struggle, despite being drained and worn out, it’s time to take it seriously. Many nights of poor sleep can take a huge toll on your overall physical, mental and emotional health. Chronic sleep deprivation not only causes daytime sleepiness, fatigue and reduced productivity but also increases the risk of certain health conditions such as high blood pressure, type 2 diabetes, depression, obesity, heart attack and even cancer.
Your sleep status depends on a lot of factors, such as your age, stress levels, hormonal imbalance, irregular working hours, physical activity or lack thereof and chronic health problems (such as hyperthyroidism). And it appears that nutritional deficiencies can impact sleep too.  Let's look at how a lack of certain vitamins and minerals can affect your sleep quality and even trigger insomnia.
Magnesium is an extremely versatile mineral and your body needs it to carry out hundreds of biochemical reactions that keep the body running and working smoothly. It is required for protein and DNA synthesis, healthy muscle and heart function, well-functioning nervous system, glutathione production and detoxification.
It plays a crucial role in energy production as well as in the activation and absorption of Vitamin D, thus keeping your bones healthy and strong. If you are running low on magnesium, your body will not be able to utilise and absorb vitamin D as effectively as it should. It is because magnesium converts vitamin D into its active form and it also activates nearly all the enzymes that are involved in vitamin D metabolism. This is an important fact considering that vitamin D also plays a significant role in maintaining mood and sleep.
Coming back to the link between magnesium and sleep, some clinical trials have reported that magnesium supplements can improve the symptoms of insomnia in the elderly.  In fact, magnesium plays a very important role in how well you respond to stress, and the health benefits of magnesium extend to conditions like depression, anxiety and painful muscle cramps. All of these conditions interfere with your ability to sleep well.
Magnesium regulates the level of stress hormones and it also regulates the production of important neurotransmitters, such as serotonin and GABA. These hormones are responsible for controlling mood, stress response and sleep.
Magnesium deficiency impairs your ability to handle stress, which is a well-known trigger for insomnia or sleep disorders. In fact, magnesium deficiency and stress share common symptoms, including anxiety, inability to sleep well, irritability, headache, muscle cramps, lethargy and muscle weakness.
Magnesium relaxes the nervous system, improves sleep and reduces symptoms of depression. A 2018 study found that magnesium and Vitamin B6 supplementation reduced stress in people with low magnesium levels. 
2. Vitamin D
In addition to maintaining healthy and strong bones, vitamin D plays an integral role in regulating immunity and sleep. Vitamin D deficiency has been associated with sleep disorders and poor sleep quality. 
Low levels of vitamin D can negatively affect your sleep duration and the time it takes for you to fall asleep. It can also increase daytime sleepiness.
It is not surprising as studies show that vitamin D receptors are present in the brain areas such as the hypothalamus, that are responsible for regulating the sleep wake cycle. Vitamin D deficiency also causes bone pain and chronic widespread pain, which can result in restless and poor sleep.
So, what are vitamin D receptors?
These are the proteins present in nearly all the cells in the body, such as the cells of your immune system, intestine, lungs, heart, muscles, thyroid gland and brain.
Now, vitamin D binds to these receptors and these bound and activated receptors switch on genes that make different proteins and enzymes responsible for carrying out a wide range of functions. For example, in the intestines, the vitamin D binds to the vitamin D receptors there – activating genes that facilitate the absorption of calcium and phosphorus.
Similarly, in the immune cells, vitamin D binds to the receptors present there – turning on genes involved in the production of anti-microbial proteins, that strengthen the body's natural immunity and help fight a wide range of infections. In the brain, these receptors are present in areas that are responsible for controlling our sleep-wake cycle.
Can you improve sleep by taking Vitamin D supplements? According to some experts, we need more high-quality studies that can confirm if vitamin D supplementation can prevent sleep disorders or help improve sleep quality.
However, studies have reported that Vitamin D supplements may help in increasing sleep duration and improving sleep quality in people with sleep disorders. [5-6]
3. Vitamin B6
Your body needs Vitamin B6 for a number of functions. It is required for healthy metabolism of fats, proteins and carbohydrates. It is involved in the production of haemoglobin, helps maintain immunity and keeps your brain and nervous system functioning well.
This water-soluble vitamin plays an important role in the production of many neurotransmitters, such as serotonin, dopamine, GABA, noradrenalin and others.  All these hormones are responsible for regulating mood, emotions, memory, sleep, and stress response. Vitamin B6 is also involved in the production of sleep hormone melatonin, which helps you fall asleep at night. Melatonin plays an important role in our sleep-wake cycle, providing cues to the body that it is time to sleep. Vitamin B6 deficiency can cause symptoms such as fatigue, irritability, depression, confusion and insomnia. In fact, even a small deficiency of Vitamin B6 can disturb the production of serotonin and GABA, which can cause sleep problems.
Some studies show that improving vitamin B6 intake can minimize the risk of depression, a well-known trigger for insomnia and other sleep disorders. Fish, beef liver, poultry, eggs, potatoes, bananas and chickpeas are some good sources of vitamin B6. You can also take supplements but consider consulting with a doctor beforehand.
4. Vitamin B12
Your body needs vitamin B12 to perform a lot of functions. For example, vitamin B12 is necessary for making healthy red blood cells and DNA. It is a key nutrient in the energy production and keeps your nervous system healthy.
Anaemia, poor balance, constant fatigue, and shortness of breath are some early signs of vitamin B12 deficiency. Since it plays a role in keeping your nervous system healthy, lack of vitamin B12 can also produce neurological symptoms such as a tingling sensation in feet and hands, reduced sensation of touch, and difficulty walking.
There are not enough studies that can directly link poor B12 status to insomnia, but a severe vitamin B12 deficiency can cause depression along with other psychiatric problems such as memory loss, dementia, irritability and personality change. And poor mental health is one of the biggest risk factors for insomnia.
People with depression often have trouble falling asleep or staying asleep. (In some cases, too much stress can even cause excessive sleepiness.)
It is important to note, however, that the causes of depression and insomnia are complicated and more often than not multifactorial. So, pointing to a single trigger like a nutritional deficiency could mean taking a simplistic view of what causes depression and how it can be dealt with. But research does suggest that low vitamin B12 status increases the risk of depression [8-9].
Vitamin B12 also helps in the production of melatonin, a hormone that controls our sleep-wake cycle. With healthy amounts of melatonin being produced and released in your brain, you will find it easier to fall asleep as well as stay asleep for longer. Melatonin promotes restful and quality sleep at night. Vitamin B12 deficiency impairs the production of melatonin, which may lead to sleeping difficulties.
Calcium in sleep? You know calcium as a mineral that keeps your bone healthy. It is also involved in healthy muscle contraction and helps in the release of several important neurotransmitters. But calcium affects your sleep cycle too.
The 2007–2008 National Health and Nutrition Examination Survey found that “low calcium intake was associated with difficulty falling asleep and an increase in non-restorative sleep.” 
This article in Medical News Today reports that calcium deficiency may trigger poor REM (Rapid Eye Movement) sleep, one of the sleep stages that restores your mind and helps in learning and consolidating memory. It is a stage where you dream and your brain is active. The 'REM sleep' stage is extremely important for healthy brain development and function in both children and adults. Not getting enough REM sleep may impact how you learn and create new memories. You may feel less focused, cranky and irritable during the day. Poor REM sleep is linked with insomnia and is known to increase the risk of anxiety and depression.
It is believed that the REM phase helps the brain to respond to and resolve negative triggers. A restless REM sleep could interfere with this process and could lead to unresolved emotional distress.  When a person cannot resolve their emotional distress, it can trigger disturbing thoughts (hyperarousal) that can interfere with sleep, causing sleep deprivation and insomnia. It becomes a vicious cycle, where poor sleeping patterns (especially a disturbed REM stage) make one less capable of keeping a lid on their emotional troubles, and this causes a build-up of distress thereby making it difficult to get a good night of refreshing and restorative sleep. It is a well-known fact that poor sleep can cause poor mood, anxiety and depression.
Calcium also helps in the synthesis of melatonin. In the brain, calcium facilities the production of melatonin from tryptophan. This brings us to the studies that have explored the role of milk, and products containing milk, in improving sleep quality in some people.  Milk contains tryptophan, an amino acid that helps in the synthesis of many hormones such as serotonin and melatonin. Serotonin, the "feel good hormone", is known to improve mood and ward off anxiety and depression. This neurotransmitter works in complex ways to regulate sleep, learning, memory, mood and behaviour. And the other hormone, melatonin, helps regulate your sleep-wake cycle. This is produced by your brain when it gets dark, providing a cue to the body that it is time to prepare for sleep.
6. Vitamin C
Vitamin C is best known for its benefit in boosting immunity. It is a powerful antioxidant that is also an indispensable ingredient in the production of collagen, protein that gives form and integrity to our connective tissues. This makes vitamin C a very important micronutrient for the health of your heart, bone, skin, eyes and teeth. But it is little known that vitamin C also plays a role in improving sleep, especially in the elderly.
We know that stress and anxiety can negatively affect sleep, both in terms of quality and quantity. In addition, lack of sleep can increase your stress levels. This vicious combination of sleep deprivation and stress can cause a wide range of health problems affecting your mental and physical well-being. Vitamin C supplementation is known to improve mood, improve symptoms of depression and reduce stress levels.  In fact, your adrenal glands are among the glands that contain the highest concentrations of vitamin C. In addition, your adrenal glands use more vitamin C during stress, thus depleting its levels in the body. This means your body needs more vitamin C when you are stressed. Since we can’t make our own vitamin C, it is best to get it from a healthy diet of fresh fruits and vegetables. Taking liposomal vitamin C supplements also helps if you have absorption issues or consuming whole, uncooked foods is a challenge.
Vitamin C may also help improve symptoms in people with Restless Leg Syndrome (RLS), a condition that causes an uncontrollable desire to move your legs and this symptom generally worsens at night when a person is lying down.
RLS causes uncomfortable sensations that can be described as crawling, pulling, pins and needles and itching. This condition worsens with age and makes it difficult to fall asleep. It can be caused by a number of factors and iron deficiency is believed to be one of the most common risk factors for RLS. Nerve damage, pregnancy, certain medications, chronic use of alcohol, and kidney failure are some other possible causes. Vitamin C helps in reducing RLS symptoms as it helps the body to absorb iron.
A growing body of evidence suggests that oxidative stress is linked with sleep and sleep related disorders and that means vitamin C, as an antioxidant, may be beneficial in sleep disorders. 
- Grandner et al. Sleep symptoms associated with intake of specific dietary nutrients. J Sleep Res. 2014 Feb; 23(1):22-34.
- Abbasi et al. The effect of magnesium supplementation on primary insomnia in elderly: A double-blind placebo-controlled clinical trial. J Res Med Sci. 2012
- Pouteau et al. Superiority of magnesium and vitamin B6 over magnesium alone on severe stress in healthy adults with low magnesemia: A randomized, single-blind clinical trial. PLoS One. 2018
- Gao et al. The Association between Vitamin D Deficiency and Sleep Disorders: A Systematic Review and Meta-Analysis. Nutrients. 2018
- Huang W, Shah S, Long Q, Crankshaw AK, Tangpricha V. “Improvement of pain, sleep, and quality of life in chronic pain patients with vitamin D supplementation.” Clin J Pain. 29.4(2013): 341-347.
- Majid et al. The effect of vitamin D supplement on the score and quality of sleep in 20–50 year-old people with sleep disorders compared with control group. Nutritional Neuroscience. 2018.
- Kohji Sato. Why is vitamin B6 effective in alleviating the symptoms of autism? Med Hypotheses. 2018.
- Syed EU et al. Vitamin B12 supplementation in treating major depressive disorder: a randomized controlled trial. Open Neurol J. 2013; 7():44-8.
- Sangle et al. Vitamin B12 Supplementation: Preventing Onset and Improving Prognosis of Depression. Cureus. 2020.
- Grandner et al. Sleep symptoms associated with intake of specific dietary nutrients. J Sleep Res. 2014 Feb; 23(1):22-34.
- Wassing et al. Slow dissolving of emotional distress contributes to hyperarousal. PNAS. 2016.
- Komada et al. The Effects of Milk and Dairy Products on Sleep: A Systematic Review. Int J Environ Res Public Health. 2020.
- Moritz et al. The role of vitamin C in stress-related disorders. J Nutr Biochem. 2020
- Aneta Otocka-Kmiecik and Aleksandra Król. The Role of Vitamin C in Two Distinct Physiological States: Physical Activity and Sleep. Nutrients. 2020.