How Sleep Affects Your Immune System

The importance of sleep can’t be underestimated. It is needed to recharge both your body and your mind and is the cornerstone of health and wellbeing.

Many people understand the important connection between sleep and health, but are still falling short of the recommended amounts of sleep which can lead to sleep deprivation.

Sleep deprivation can set the stage for various short term and long term health consequences.

According to a study published in the Nature and Science of Sleep, some short-term consequences of sleep deprivation can include increased stress, reduced quality of life, increase in mood disorders, and deficits in cognition and memory.

Long-term consequences of sleep deprivation may include an increased risk of cardiovascular disease, weight gain, type 2 diabetes, and colorectal cancer.

Additionally, lack of sleep can suppress your immune system while adequate sleep can strengthen it.

While both good nutrition and a hygienic lifestyle play an integral role in keeping you from getting sick, nothing compares to healthy sleep patterns to keep your immune system in top shape.

Sleep and Your Immune System

There is a very strong connection between sleep and your immune system. Getting enough quality sleep can help support your immune system as it protects your body from illness and disease.

Conversely, lack of sleep can interfere with the healthy functioning of your immune system, leaving you more susceptible to infections.

When you sleep, your body releases cytokines which are proteins that act as messengers for your immune system. Cytokines can help reduce infection and decrease stress within your body.

Research suggests that even if you aren’t sick, the release of cytokines can strengthen your immune response to help fight off an infection when needed.

Therefore, adequate, quality sleep and the production of cytokines is essential for your body’s ability to fight illnesses. This is why your body tends to sleep more when you’re feeling under the weather.

Meanwhile, sleep deprivation can decrease the production of these protective cytokines, reducing your immune system’s ability to fight infections and repair cells.

During sleep, your body also produces T-cells. T-cells are white blood cells that play a vital role in your body’s immune response to infection and disease.

One 2019 study found that a good night’s sleep can enhance the effectiveness of T- cell functioning which can bolster your body’s defenses against infection.

Besides feeling sluggish, your body will also react to sleep deprivation by producing c-reactive protein (CRP). CRP is a protein that is a marker for inflammation within the body.

Research indicates that markers of inflammation, such as CRP, have been linked to poor sleep, with higher levels of this marker associated with research participants experiencing impaired sleep patterns.

High CRP levels have been shown to suppress T-cell function in animal and human models.

Additionally, increased levels of CRP have been linked to an increased risk of heart disease.

Lack of sleep and the immune system are clearly connected, but can a good night’s sleep really keep you from getting sick? Perhaps.

One 2015 study found that people with healthy sleep habits, meaning those who slept more than 7 hours per night, were far less likely to get sick after being exposed to the common cold.

How Much Sleep Do You Need Each Night?

Most adults need about 7 to 8 hours of good-quality sleep per night.

This amount reflects the ideal amount of sleep under normal circumstances, but there are cases when you’ll benefit from more than the recommended amount. For example, if you’re recovering from an illness, experiencing jet lag, or are overworked and overstressed, your body may require more than 7 to 8 hours of sleep each night.

If you’re struggling to get the recommended amount of sleep every night, you are not alone. In fact, according to the Centers for Disease Control (CDC), roughly 32% of adults in the US report sleeping less than 7 hours per night on average.

Aiming for 7 to 8 hours of quality sleep per night will require you to create and maintain strong sleep hygiene, or sleep health.

The following are tips to help improve your sleep hygiene:

• Sleep in a comfortable and dark environment free of disruptions.
• Keep a stable and consistent sleep schedule.
• Eliminate the use of electronics 30 minutes before going to bed.
• Don’t nap for more than 30 minutes during the day.
• Try to stick to a regular exercise routine during the day.
• Limit alcohol and caffeine intake in the evenings.

Because sleep and immunity are so strongly connected, if you’re feeling sick, getting adequate sleep is vital to healing and conserving energy to help your body fight off an illness.

If you’re healthy, getting adequate, good quality sleep can help your immune system operate at full capacity to keep you feeling healthy and functioning optimally throughout the day.

References

1. Medic G, Wille M, Hemels ME. Short- and long-term health consequences of sleep disruption. Nat Sci Sleep. 2017;9:151-161. Published 2017 May 19. doi:10.2147/NSS.S134864
2. Irwin MR. Sleep and inflammation: partners in sickness and in health. Nat Rev Immunol. 2019 Nov;19(11):702-715. doi: 10.1038/s41577-019-0190-z. PMID: 31289370.
3. Stoyan Dimitrov, Tanja Lange, Cécile Gouttefangeas, Anja T.R. Jensen, Michael Szczepanski, Jannik Lehnnolz, Surjo Soekadar, Hans-Georg Rammensee, Jan Born, Luciana Besedovsky; Gα_s-coupled receptor signaling and sleep regulate integrin activation of human antigen-specific T cells. J Exp Med 4 March 2019; 216 (3): 517–526. doi: https://doi.org/10.1084/jem.20181169
4. Dzierzewski, J. M., Donovan, E. K., Kay, D. B., Sannes, T. S., & Bradbrook, K. E. (2020). Sleep inconsistency and markers of inflammation. Frontiers in Neurology, 11. https://doi.org/10.3389/fneur.2020.01042
5. Yoshida T, Ichikawa J, Giuroiu I, et al. C reactive protein impairs adaptive immunity in immune cells of patients with melanoma. Journal for ImmunoTherapy of Cancer 2020;8:e000234. doi: 10.1136/jitc-2019-000234
6. Cozlea DL, Farcas DM, Nagy A, et al. The impact of C reactive protein on global cardiovascular risk on patients with coronary artery disease. Curr Health Sci J. 2013;39(4):225-231.
7. Prather AA, Janicki-Deverts D, Hall MH, Cohen S. Behaviorally Assessed Sleep and Susceptibility to the Common Cold. Sleep. 2015;38(9):1353-1359. Published 2015 Sep 1. doi:10.5665/sleep.4968
8. CDC – Data and Statistics – Sleep and Sleep Disorders. (2021). Retrieved 7 December 2021, from https://www.cdc.gov/sleep/data_statistics.html