Vitamin C and Sleep: Is There a Link?

  • By Performance Lab
  • 6 minute read
Vitamin C and Sleep: Is There a Link?

Many people are familiar with the role of vitamin C in immune health. Knocking back a glass of vitamin C-rich OJ can help boost your immune system and fend off that nasty cold taking over your face.

Or maybe you know it for its ability to enhance wound repair. Whatever the job is, vitamin C is essential for normal physiological function.

But did you know that vitamin C can also support better sleep?

Most people aren’t familiar with its role in sleep, and studies suggest that people with higher levels of vitamin C have better sleep and are more resilient to occasional sleep loss.

Ready to find out why? This article dives into everything you need to know about vitamin C and sleep—plus how you can fulfil your vitamin C requirements and get the best sleep of your life.

What Is Vitamin C?

Vitamin C, also called ascorbic acid, is a water-soluble vitamin that’s always been known for its role in immune health—but it does much more than just strengthening your immune system.

Because it’s water-soluble, vitamin C must be replaced daily to ensure high levels, as excess is not stored and excreted in the urine.

While some mammals can produce vitamin C, humans lack the enzyme—gluconolactone oxidase—needed to make ascorbic acid 1. As such, it must come through diet or supplementation.

Besides its role in supporting immune function, what else does vitamin C do? It’s involved in:

  • Collagen synthesis and wound repair
  • Bone formation
  • Blood vessel integrity
  • Antioxidant defenses and regeneration
  • Immune function
  • Nitric oxide bioactivity
  • Neurotransmitter synthesis
  • Maintaining iron stores
  • Cognitive function
  • Mood

One of its other prominent roles is as a powerful antioxidant. Vitamin C can act as a potent free-radical scavenger and help regenerate vitamin E because it functions as an electron donor (and, therefore, a reducing agent).

Most of its physiological and biochemical actions are attributed to this role 1. When other molecules react with a free radical, they lose an electron on their outer shell, which causes them to become unstable and highly reactive.

Vitamin C, however, remains relatively stable with one less outer electron, which means it can effectively scavenge radicals without itself becoming one.

While vitamin C is essential for cardiovascular health, cognitive function, bone health, immunity, and more, its benefits may also extend to sleep.

Benefits Of Vitamin C For Sleep

1. Sleep Quality And Duration

If you’ve had dreams about getting the most epic sleep of your life but haven’t been able to make it a reality, it might be worth looking at your nutrient intake, especially vitamin C. While low intakes of vitamin C are typically linked to weakened immune defenses, low levels could also interfere with sleep quality and duration.

According to a study published in Appetite, people who only slept six hours per night had lower levels of vitamin C than people who slept longer 2.

That said, supplementing vitamin C likely isn’t going to help you sleep longer, but there is a proposed link between sleep duration and vitamin C levels, suggesting that lower levels increases nightly sleep disturbances and heightens the risk for sleep disorders.

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On top of that, a small study found that people who ate two kiwis each day—kiwis contain 142% of the DV of vitamin C—an hour before bed slept 13% longer than those who didn’t eat the kiwi and fell asleep faster 3.

But there’s another way to get a good night’s rest—Performance Lab Sleep. While it may not contain vitamin C—you can get that with Performance Lab NutriGenesis Multi—it does have natural melatonin from Montmorency cherries plus three forms of magnesium to relieve tension and help you drift off to la-la land quickly.

2. May Relieve Movement Disorders

Although it’s not the most common disorder, restless leg syndrome (RLS) can wreak havoc on your sleep. People with restless leg syndrome have an uncontrollable urge to move their legs at rest.

Some people experience pain or the sensation of carbonation in the veins, and relief only comes with standing or moving their legs. Period limb movements (PLM) are also common in people with RLS at night, drastically reducing sleep efficiency 4.

But there’s good news—studies show that vitamin C effectively improves sleep quality, itching, and restless legs syndrome 5. Although the exact mechanism isn’t known, iron deficiency can be a cause of RLS, and vitamin C improves the absorption and storage of non-heme iron.

3. Improves OSA

Obstructive sleep apnea (OSA) is a condition whereby the airways become blocked during sleep, making breathing challenging. People with OSA often stop breathing for seconds at a time and wake up with a large, deep gasp for air.

The abrupt awakenings that come with OSA make it challenging to get enough quality sleep, so people often wake feeling unrested. However, vitamin C supplementation has been shown to improve symptoms of obstructive sleep apnea.

A 2009 study found that combining 100mg vitamin C with 400 IU vitamin E twice daily reduced episodes of apnea—the breathing interruptions characteristic of the condition. The vitamin combination also improved sleep quality and decreased daytime sleepiness 6.

One of the other things that come with sleep apnea is an increased risk of cardiovascular disease 7. Left untreated, obstructive sleep apnea can lead to high blood pressure and metabolic issues (obesity, arrhythmia, cardiovascular complications).

OSA happens when the endothelial lining (lining of the blood vessels) malfunctions, interfering with blood circulation 8. But the superstar nutrient swoops in to improve endothelial function, potentially mitigating some of the stress on the vascular systems linked to OSA 9.

Other Benefits Of Vitamin C

While vitamin C may benefit those struggling with sleep, it has plenty of other essential roles in maintaining optimal function:

Strengthens The Immune System

Vitamin C’s immune-boosting powers are one of its most notable functions. It’s required for effective immune responses by supporting the adaptive and innate arms of the immune defense system and scavenging free radicals that can damage cells and lead to oxidative stress and inflammation 10; high levels of oxidative stress are heavily involved in the development of chronic and degenerative diseases.

It’s also essential for strengthening mucosal barriers and supporting the differentiation and proliferation of B and T-cells 11, 12.

And if you want to ensure you’re getting enough vitamin C to support immune function, consider popping back PL-Immune daily. It’s a dynamic immune supplement designed to supercharge every aspect of your immune system for robust immune responses and broad-range immune support.

Neurotransmitter Synthesis And Mood

Vitamin C is required for regulating neurotransmitter biosynthesis, especially of the catecholamines dopamine, norepinephrine, and epinephrine 13.

It acts as a cofactor for dopamine β-hydroxylase, which converts dopamine to norepinephrine. Because of this, it’s essential for regulating brain function and mood.

Maintains Healthy Connective Tissues

Vitamin C is essential for two enzymes involved in collagen synthesis: prolyl hydroxylase (stabilizes the collagen molecule) and lysyl hydroxylase (provides structural strength cross-linking) 14.

Collagen forms the basis of all connective tissues (tendons, ligaments, bone, skin, blood vessels, etc.). Low levels have been linked to dermatological symptoms, bone and joint problems, bleeding gums, and more.


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