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Defining Stress

What is stress? Moreover, what are the causes of stress and the long-term consequences on our health? This article explores the topic of stress in-depth and provides a means of viewing stress from an Integrative East-West perspective.

In This Article:

What is Stress? [1,2]
According to one of the first researchers to examine stress, stress is “[t]he non-specific response of the body to any demand for change.” Stress can come in a variety of different forms ranging from moderate stress that challenges individuals to accomplish certain tasks to high levels of constant stress leading to chronic diseases.

Types of Stress [3,4]
- Physical stressors include surgery, repetitive manual labor, over-exercising, or fatigue
- Metabolic stressors include chronic inflammation, hormonal imbalance, exposure to toxins, caloric restriction, or excessive caloric intake
- Psychosocial stressors include experiences with death, divorce, anxiety due to situations such as public speaking, examinations, or other stressful circumstances

Common Causes of Stress [5]
A wide range of situations can manifest in feelings of stress. Typical stressors, such as test anxiety and fear of public speaking, are short-term and do not typically result in detrimental long-term health consequences. On the other hand, chronic stress culminates in serious health conditions. Common causes of chronic stress may be one or more of the following:

  • Frequent Illnesses
  • Relationship Problems
  • Major Life Changes
  • Problems at Work
  • Lack of a Supportive Environment
  • Lack of Healthy Outlets of Stress

Acute Stress vs. Chronic Stress [6]
Stress can be characterized as acute or chronic depending on its duration.

  • Acute Stress: Acute stress is commonly known as the “fight-or-flight” response and is the body’s immediate response to a perceived threat.
  • Chronic Stress: Chronic stress results when a stressful situation persists for a long period of time.

Consequences of Stress [1]
When experiencing stress, the immediate symptoms commonly include a faster heart rate, a headache, stiffness in the neck and shoulders, back pain, sweating, upset stomach, and much more depending on the person and situation. However, repeated stress can have more profound consequences such as suppressing the immune system, increasing the risk of heart disease, prolonged neck, shoulder, and back pain, decreased fertility and libido, irregular menses, digestive disorders, eating disorder, sleep disturbance, respiratory disorders, and skin problems. Stress can also increase your irritability, decrease your patience, and in some cases heighten your hostility to others.

Physiologic Changes from Chronic Stress [7,8,9]
Because of the brain’s major role in an individual’s perception of and reaction to stress, it is not surprising that the neural circuitry in the brain can be altered in response to these stressors. In fact, brain plasticity allows people to adapt to stress in a way that allows the body to regain homeostasis.

According to a 2000 study published in Neuropsychopharmacology, the primary stress hormones, glucocorticoids and catecholamines, are necessary in the short run for allostasis (the maintenance of homeostasis through the adaptation to short-term stress), but detrimental if produced continuously over an extended period of time, resulting in allostatic load, what researchers describe as “the wear-and-tear on the body and brain.” While allostasis is imperative for adaptation, homeostasis, and survival, allostatic load can culminate in increased vulnerability to certain diseases due to maladaptive changes in the brain from stress-induced alterations. Because of the mind-body interaction, long-term stress-induced plasticity of the brain can result in maladaptive effects on metabolic processes, immune and cardiovascular system, and other essential operations of the body, resulting in impaired mental and physical health.

Stress and the Adrenal Glands
The adrenal glands, which are located on top of each kidney, are essential for regulating many body functions, such as the “fight-or-flight” response to stress and balance of salt and water, blood sugar levels, and overall homeostasis through the release of hormones. [10]

In the past, an additional energy boost from an “adrenaline rush” from the adrenal glands served as a beneficial adaptation measure to help our ancestors escape from life threatening situations in the wilderness. However, the constant release of stress hormones, like adrenaline, cortisol, and dehydroepiandrosterone (DHEA), in response to continuous stressors of today’s world can result in hormonal imbalances and adrenal dysfunction.

With high levels of stress, the adrenal glands are overtaxed for cortisol production which cannot be sustained for extended durations. Consequently, adrenal imbalance will often result in individuals consistently finding themselves in stressful situations. Symptoms of adrenal dysfunction include sleep disturbances, insomnia, anxiety, depression, suppressed immune system, and allergies. [11]

Viewing Stress from the Perspective of Integrative Medicine
From the perspective of Integrative East-West medicine, stressors include not only psychosocial elements but also encompass factors such as pathogens, environmental changes, and metabolic stressors that induce direct or indirect damage to the body.


  1. WebMD: Stress Management Health Center. Stress Management-Effects of Stress. WebMD. Accessed at http://www.webmd.com/balance/stress-management/stress-management-effects-of-stress on September 9, 2012.
  2. What is Stress? The American Institute of Stress. Accessed at http://www.stress.org/what-is-stress/ on September 9, 2012.
  3. Fatigue and Adrenal Dysfunction. Centre for Natural Medicine. Accessed at http://www.naturalmedicine.mb.ca/pdf/May%2007/Adrenal%20article.pdf on September 9, 2012.
  4. Epel, E (2009). Psychological and metabolic stress: A recipe for accelerated cellular aging? Hormones, 8(1):7-22.
  5. WebMD: Stress Management Health Center. Stress Management-Causes of Stress. WebMD. Accessed at http://www.webmd.com/balance/stress-management/stress-management-causes-of-stress on September 9, 2012.
  6. Mayo Clinic: Stress Management. Stress management: Identify your sources of stress. Mayo Clinic. Accessed at http://www.mayoclinic.com/health/stress-management/SR00031 on September 9, 2012.
  7. McEwen, BS, Gianaros, PJ (2011). Stress- and Allostasis-Induced Brain Plasticity. Annual Review of Medicine. 62:431-45.
  8. McEwen, BS (2000). Allostasis and Allostatic Load: Implications for Neuropsychopharmacology. Neuropsychopharmacology. 22:108-124.
  9. McEwen, B & Gianaros, P (2010). Central role of brain in stress and adaptation: Links to socioeconomic status, health, and disease. Ann N Y Acad Sci, 1186: 190-222.
  10. Health Information: Adrenal Gland Disorder. National Institutes of Health: Eunice Kennedy Shriver: National Institute of Child Health & Human Development. Accessed at http://www.nichd.nih.gov/health/topics/adrenal_gland_disorders.cfm on September 9, 2012.
  11. Patient Education Information. Adrenal Hormone Imbalance and Adrenal Fatigue. Compounding Specialist of Wyoming. Accessed at http://www.wyomingcompounding.com/files/Adrenal_Fatigue_Information.pdf on September 9, 2012.

By Shannon Wongvibulsin, BS Candidate, UCLA 2014
UCLA Center East-West Medicine, Staff Writer

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