Sunday 3 June 2012

Stress: A Killer or Essential for Survival

The following article is based on "Stress: Portrait of a Killer" by PBS National Geographic.

  Everyone knows it, almost everyone have experienced it sometime, in smaller way during our everyday chores, or in extreme level during some important events. Exams, deadlines, problems, crisis - all of them have one thing is common - Stress. Its everyone's inferno - but do it has any purpose behind? Why is our brains wired so that we have this experience of stress in first place? Does it solves anything, or it has any evolutionary purpose?
  Stress does have a purpose - to save us, to guide us, to keep us into the direction that we should be going. This may sound strange because we have a negative connotation when we talk about stress, but it actually do have a purpose, even has an evolutionary benefit.
  Stress is not state of mind, its something measurable and could turn out to be dangerous at extreme levels. If we talk about any normal mammal except most primates; for them stress is something that may just last as few minutes of screaming and rigor, after which either stress is over or they are no more alive. The role of stress for them is when they are being chased, or they are chasing someone - and there is an immediate crisis going on. However for primates - with larger brain, though their caloric needs are increased - but still brain has an advantage; since now they don't have to chase long to fill their caloric requirements, neither they are often being chased by some predator. They are not stressed by these, rather they are stressed by the social and psychological turmoils brought by their own species.
  When an animal is stressed running for their life or when we bring stress for other reasons; the basics are same - lungs start working overtime to pump enough quantity of oxygen in blood stream and heart races to pump that oxygen throughout the body. But for an animal, once it escapes this crisis, their stress response shuts down; however for human beings, it cant seem to find the off switch.
  Stress is a mean by which body prepares itself to rise up to any challenge; whether that challenge is life threatening, trivial or just for fun. If we get right amount of stress, then we consider it as stimulation or motivation. Two hormones central to stress response are - Adrenaline (or Epinephrine) and Glucocorticoids. The goal of life should not be to avoid stress, rather goal should be to have right type of stress and in right quantity - then we may even start liking it, and a very trivial example of that would be roller coaster rides.
  In baboon society, its found that those who are higher in hierarchy are generally less stressful. Or looking it in a different way, those who are less stressful, happen to be healthy and bigger, making them dominant and gets higher in hierarchy.
  Similarly in our work culture, those who are apt in handling stressful situations, who knows the way out of it are more likely to go higher in work hierarchy. As compared, those who lack the ability to handle stressful situations, are more likely to perform not up-to their potential even though skilled, and so fail to attain those higher levels.
  As quite expected, stress beyond a certain level, the level after which in our general terms we start experiencing its ill effects and start considering it as stress - has some real bad effects for our health and well being in long terms.
  30 years back, ulcers were considered as the very cause of stress and persons state of mind. Later Australian scientist figured that ulcers are actually caused by a bacteria, and later cure was found and pills were developed. But this finding brought some new interesting questions - this bacteria is found in almost 2/3 of world population, but then why does it causes ulcers in just fractions of them?
  Research revealed that when a person is under stress then body begins to shut down all non essential systems, including some of immune system activities. Its quite clear that when immune system is shut down, stomach bacteria can run wild! So stress causes to shut down the ability of body to repair stomach walls, after they gets damaged by this bacteria; and that explains how the stress can be the reason for causing ulcers in few.
  Acute stress can go as bad as damaging the brain cells. Its very well known that acute stress affects the hippo-campus region of the brain and thus causes the person to lose the ability to make new memories. In worst situation, it may even damage parts of brain cells causing to lose some of the previous memories as well. Not an acute situation, but a perfect realization of this could be, and I think everyone can relate to this as well - times when we stress our minds before exams, staying late at nights; but just before the exam, we get a feeling that we don't remember anything at all.
  Stress can also change the way a person deposits fats, the way it gets distributed across the body. Those who are stressful are likely to have fat mostly distributed more towards center, i.e. abdomen region. Fat deposit on trunk or inside the abdomen are more dangerous than those deposited else where in the body, since they produce different kind of hormones and chemicals that affect body in a more worst ways.
  Another evil of stress could be accelerated aging, and though its been realized quite long time, reason for it is a rather newer and an interesting finding. Telomers are ends of chromosomes (a repetitive nucleotide sequence) that protects the chromosome from deterioration and from fusing with neighboring chromosomes, just like the plastic caps we have on shoelace. Over time, with each cell division, the telomer ends become shorter as not whole of chromosome sequence gets copied. Its claimed that once the telomer end reaches a certain critical level, then from that point the cell can no longer divide, becomes inactive and eventually dies. According to recent finding, the stress causes an increase in the rate of telomer degradation and hence increased aging process. The length of a persons telomer can directly be related to age, and how much stress they are into and for how long.
  Last but not the least, is the way stress affect personal experiences of a person. With stress, one become incapable to experiencing the same amount of pleasure into things that other less stressful one might experience and enjoy. Pleasure feeling is related to the level of dopamine receptors in the brain. Those who are stressed are found to have lower levels of these receptors. So effectively for them sun don't shine as bright or food don't taste as good. 
  I end this article with words from my father that says these same thing, but rather in a more beautiful and concise way - 
 Dil mein jo ho umang to har saha bhali lage,
       warna bhali sii cheez bhi dil ko buri lage.
Kuch aisa kar dikhao, jamaane me dosto,
      ki jiske baad phir tumhari kami lage.