What do you think of when you hear “lack of sleep?” The urge for a daytime nap and multiple trips to the coffeemaker to load up on caffeine? Reduced productivity, forgetfulness, and easily made mistakes?

It's easy to spot how a lack of sleep impacts your energy level or ability to think. What’s not as apparent, however, is how not getting enough sleep can adversely affect your immune system and the negative consequences it has on your body.

The immune system-sleep connection

The immune system has one primary role: to protect you. It neutralizes harmful substances you encounter in the environment. It identifies invaders, such as viruses and bacteria, and removes them from your body. It looks for unhealthy changes in cells, such as cancer cells, and mounts an attack.1

When your immune system kicks in to protect you from a threat, it can impact the amount of sleep you need. For example, you might feel tired or find yourself sleeping longer while your body fights off a virus. Getting adequate sleep supports immune function by ensuring there are enough immune cells circulating in your body.2,3

Without adequate sleep – at least seven hours a night for most adults – your body produces fewer protective substances, including infection-fighting antibodies and cells. This can increase the risk of an upper respiratory infection or other illness.2,3

Not getting enough sleep can also negatively impact vaccinations, weakening your body’s response to an immunization and reducing its effectiveness. On the other hand, getting adequate sleep before a vaccination can improve the body’s immune response.2-4

Lack of sleep is associated with multiple ailments

Not getting enough sleep affects more than your ability to fight off an infection. A lack of sleep also appears to trigger constant, low-grade inflammation in the body. This inflammation can lead to cellular and tissue damage, which can contribute to many health problems.2

Although more research is needed, evidence suggests a lack of sleep might influence the following conditions.

Cancer

Some studies link insufficient sleep to hindering the body’s anti-tumor response and might increase the risk of breast, colorectal, and prostate cancers. Another possible explanation is that a lack of sleep decreases the activity of the anticancer immune cells called natural killer cells.2,4 Some research indicates a lack of sleep might lead the body to produce less of the hormone melatonin at night, lessening the overall amount circulating in the body.4 In addition to regulating the sleep cycle, melatonin functions as an antioxidant, an anti-inflammatory, and regulator of the immune system. Although more research is needed, recent studies have described the anticancer effects of melatonin and its ability to inhibit different types of cancer.4-6

Neurodegenerative diseases

It's believed that Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, Huntington’s disease, and amyotrophic lateral sclerosis (ALS) cause a person to sleep less. But other research points to shortened sleep as contributing to the development or worsening of these conditions. During sleep, your immune system is busy clearing the brain and spinal cord of the proteins that build up during the day. When sleep is in short supply, these proteins can accumulate – a hallmark of neurodegenerative diseases. Amyloid beta (Aβ) protein, for example, is primarily cleared from the brain during sleep. In studies, sleep deprivation led to Aβ accumulation and plaque development, which are part of the Alzheimer’s disease process.4

Autoimmune disorders

Research suggests that sleep deprivation might encourage the breakdown of immunologic self-tolerance – the ability of the body to recognize its own substances so it doesn’t mistakenly attack them. Studies have found that individuals with sleep disorders have a high risk of developing autoimmune conditions, such as rheumatoid arthritis. It’s thought that sleep deprivation accelerates the disease process by increasing the production of pro-inflammatory substances called cytokines.4,7

Heart disease and related conditions

Regularly getting fewer than seven hours of sleep a night is often linked to increased risks of vascular problems, such as coronary heart disease and stroke. In addition, research indicates that individuals who average fewer than five hours of sleep a night have the greatest chance of developing cardiovascular problems in general. Not getting enough sleep is linked to atherosclerosis – the narrowing or hardening of the arteries due to plaque buildup. This might be because sleep deprivation promotes endothelial dysfunction, a breakdown in the functioning of the thin layer of cells inside the blood vessels. Sleep loss can also lead to developing risk factors for heart disease, including a greater likelihood of obesity, insulin resistance, type 2 diabetes, and high blood pressure.4

Reclaiming your sleep

Although getting more sleep might seem like the least urgent change you need to make in your life, the truth is that good quality sleep is crucial. To help improve your sleep:8

1. Stick to a sleep schedule. Go to bed and get up at the same time every day, including weekends. Being consistent reinforces your body's sleep-wake cycle.

2. Pay attention to what you eat and drink. Don't go to bed hungry or stuffed. Minimize nicotine, caffeine, and alcohol intake. The stimulating effects of nicotine and caffeine take hours to wear off and can interfere with sleep. Although alcohol might make it easier to fall asleep, it disrupts sleep later in the night.

3. Create a restful environment. Keep your room cool, dark, and quiet. Exposure to light in the evening can make it more difficult to fall asleep. Avoid prolonged use of blue light-emitting screens just before bedtime.

4. Include physical activity in your daily routine. Regular physical activity promotes better sleep. However, avoid being active too close to bedtime.

5. Manage worries. Resolve your worries or concerns before bedtime. Jot down what's on your mind and then set it aside until tomorrow.

If you still struggle with sleep, then consider consulting with a health-care professional. You might have an underlying condition or a sleep disorder that is keeping you from getting the rest you need.

A word from Thorne

In addition to melatonin, several other nutrients or botanicals have been shown to support restful sleep.* Explore Thorne’s sleep support supplements.

References

  1. How does the immune system work? Institute for Quality and Efficiency in Health Care (National Library of Medicine). https://www.ncbi.nlm.nih.gov/books/NBK279364/. [Accessed June 10, 2023]. 
  2. Boosting your immune system. Mayo Clinic Health Letter. Mayo Clinic. Special issue: Understanding immune system health. 2021. 
  3. Lack of sleep: Can it make you sick? Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/insomnia/expert-answers/lack-of-sleep/faq-20057757. [Accessed June 10, 2023] 
  4. Garbarino S, Lanteri P, Bragazzi NL, et al. Role of sleep deprivation in immune-related disease risk and outcomes. Commun Biol 2021; 4:1304. 
  5. Talib WH, Alsayed AR, Abuawad A, et al. Melatonin in cancer treatment: current knowledge and future opportunities. Molecules 2021;26(9):2506.  
  6. Wang L, Wang C, Choi WS. Use of melatonin in cancer treatment: where are we? Int J Mol Sci 2022;23(7):3779.  
  7. Immune tolerance. National Institute of Allergy and Infectious Diseases. https://www.niaid.nih.gov/research/immune-tolerance. [Accessed June 10, 2023] 
  8. Sleep tips: Six steps to better sleep. Mayo Clinic. https://www.mayoclinic.org/healthy-lifestyle/adult-health/in-depth/sleep/art-20048379. [Accessed June 10, 2023.]