Question: I have frequently heard that stress can have negative health effects, even to the point of having a shorter life expectancy than someone who experiences less stress. I want to know how stress can do this.

Answer: Stress is the cumulative reaction to an environmental change (1). Stress can be acute meaning it is intense, and short-term such as a car accident, or chronic meaning it is experienced repeatedly, long term such as caring for a person with a dementia(2). Acute stress can be adaptive allowing organisms to survive an environmental pressure, but chronic stress may cause depression, anxiety, cardiovascular disease, obesity, sexual dysfunction, skin and hair problems, and/or gastrointestinal problems(3). Rats exposed to chronic stress had morphological changes in their prefrontal cortex correlating with impaired response inhibition, motivation and transiently impaired working memory(4). Steroid hormones called Glucocorticoids play a key role in the physiological response to stress(5). The prominent glucocorticoid found in mammals is cortisone(5). An increase in cortisol leads to downregulation of growth, immunity, reproductive drive, and digestion(6). Chronically elevated levels of cortisol can suppress the immune system, increase blood pressure and blood sugar levels, and decrease libido(6). Epinephrine also plays a key role in the physiological response to stress. Long term elevation of epinephrine is associated with cardiovascular disease, and immune suppression(8). Perceived stress and length of time sustaining stress is positively correlated accelerated telomere shortening(7). Accelerated telomere shortening is associated with cell senescence and death(7). However, the mechanism linking accelerated telomere shortening and stress in still unknown.

Tiffany E.

Sources

  1. Stress. (n.d.) Gale Encyclopedia of Medicine. (2008). Retrieved June 23 2016 from http://medical-dictionary.thefreedictionary.com/stress
  2. Acute vs. chronic stress. (n.d.). Retrieved June 23, 2016, from http://www.humanstress.ca/stress/understand-your-stress/acute-vs-chronic-stress.html
  3. Stress Symptoms: Effects of Stress on the Body. (n.d.). Retrieved June 23, 2016, from http://www.webmd.com/balance/stress-management/stress-symptoms-effects_of-stress-on-the-body
  4. Mika, A., Mazur, G. J., Hoffman, A. N., Talboom, J. S., Bimonte-Nelson, H. A., Sanabria, F., & Conrad, C. D. (2012). Chronic Stress Impairs Prefrontal Cortex-Dependent Response Inhibition and Spatial Working Memory. Behavioral Neuroscience, 126(5), 605–619. http://doi.org/10.1037/a0029642
  5. Bowen, R. “Glucocorticoids.” Glucocorticoids. Colorado State University, 26 May 2006. Web. 28 June 2016. http://www.vivo.colostate.edu/hbooks/pathphys/endocrine/adrenal/gluco.html
  6. Klein, S. (2013, April 19). Adrenaline, Cortisol, Norepinephrine: The Three Major Stress Hormones, Explained. Retrieved June 23, 2016, from http://www.huffingtonpost.com/2013/04/19/adrenaline-cortisol-stress-hormones_n_3112800.html
  7. Epel, E.S.,, Blackburn, E.H., Lin, J., Dhabhar, F.S., Adler, N.E., Morrow, J.D., Cawthon, R.M. Accelerated telomer shortening in response to life stress. (2004). PNAS. Vol. 101 no.49 p.17312-17315.
  8. Wong, D.L., Tai, T. C., Wong-Faull, D. C., Claycomb, R., Meloni, E.G., Myers, K. M.,Carlezon W. A. Jr., Kvetnansky, R. Epinephrine: A Short- and Long-Term Regulator of Stress and Development of Illness. (2012).Cellular and Molecular Neurobiology.  Vol. 32: 5. pp 737-748.
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