The Science Behind Why Exam Season Makes Us Sick

By Agamvir Hans

Here on campus, a very recognizable pattern starts to emerge as exam season approaches. Students' sleep routines fall apart as libraries fill up, and many find themselves suddenly reaching for tissues and cold remedies. It can often just seem unlucky to get sick during this time, but there is a compelling scientific explanation for why illness tends to hit at this worst possible moment. Exam season is characterized by stress and sleep deprivation, which can significantly affect the immune system and increase the body’s overall susceptibility to illness.¹

Our body’s natural reaction to pressure is stress, which can actually be beneficial in moderation.  This has been seen as some short term stress causes the production of chemicals that boost energy and alertness such as cortisol and adrenaline.² However, on the other hand, stress frequently turns into a chronic condition during exam season and it can seem never ending.  The chronic increase of cortisol levels starts to impair immune function. The harmful effects cause white blood cells, our infection fighters, to be less active in the presence of elevated cortisol, which makes it more difficult for the body to react to any germs and/or viruses it may come into contact with.^3,4 In essence, when the body tries to concentrate on managing continuous stress, the immune system enters a low priority state. The additional lack of sleep experienced further impairs immunity. Sleep is always an active time for immunological maintenance, not just for relaxation. The body releases cytokines which are signalling proteins that are seen to aid in controlling inflammation and immunological responses, during deep sleep.⁵ On top of this, sleep promotes the development and activity of T cells, an extremely vital subset of white blood cells that are essential for attacking infected cells. According to studies, folks who regularly sleep for fewer than six hours a night are far more susceptible to diseases like the common cold than people who get enough sleep of 8 hours or more.⁶ Students may get more hours of review when they forgo sleep in order to study, but they also unintentionally forfeit a vital layer of immunity. 

Lack of sleep and stress frequently combine to amplify one another's impacts on the body. While sleep deprivation enhances stress sensitivity the next day, high levels of stress can make it difficult to get or remain asleep for the whole night. The immune system is continuously strained as a result of this feedback loop. Over time, this imbalance may worsen inflammation and weaken the body's defences against pathogens.⁷ This combination helps explain why, even if someone was feeling well weeks prior, students may feel exhausted or even sick just before exams begin.

Understanding this basic biology helps explain why certain behaviours are important, but it does not imply that stress or sleep deprivation can be totally avoided before tests. Some form of regular sleep cycles are better than sporadic “all nighters.” This is the case even if they are shorter than the usual sleep you get during the year. Taking frequent walks or deep breathing are examples of quick stress relieving activities that can reduce cortisol levels and boost the body’s immune function.⁸ Even while these tactics are simple and may not seem like much they can have a significant impact when there is a lot of academic pressure. Exam season stresses the body from a holistic view as it limits our capacity to remain balanced under pressure, along with problem solving skills. Any exam related illness is a normal physiological response to extended stress and sleep deprivation rather than a personal shortcoming or coincidence. Students may make better decisions that promote their health and academic success by knowing how the immune system reacts to a variety of stresses. It is not a waste of time to take care of your body during a test; rather, it is part of being resilient when it counts most.

References

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3. Irwin MR. Why Sleep Is Important for Health: A Psychoneuroimmunology Perspective. Annual Review of Psychology. 2015 Jan 3;66(1):143–72.

4. Croft JB. CDC’s Public Health Surveillance of Sleep Health. SRS bulletin [Internet]. 2017;19(1):15. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC5333573/

5. Ramar K, Malhotra RK, Carden KA, Martin JL, Abbasi-Feinberg F, Aurora RN, et al. Sleep is essential to health: An american academy of sleep medicine position statement. Journal of Clinical Sleep Medicine [Internet]. 2021 Oct 1;17(10):2115–9. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8494094/

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7. Austin E, Saklofske D, Mastoras S. Emotional intelligence, coping and exam-related stress in Canadian undergraduate students. Australian Journal of Psychology. 2010 Mar;62(1):42–50.

8. Bryant PA, Trinder J, Curtis N. Sick and tired: does sleep have a vital role in the immune system? Nature Reviews Immunology [Internet]. 2004 Jun;4(6):457–67. Available from: https://www.nature.com/articles/nri1369#citeas