It’s that time of the year. Flowers blooming, sun shining. But the dark cloud of stress is looming over most of us. Exams, deadlines and everyday busyness. Is this affecting our health?
Stress is something we all experience daily in varying extremes. Like most aspects of our lives, it can be explained by ancient evolutionary functions which kept humans alive. However, what was protecting us many years ago may be harming us today. Is it good for you to be constantly overworking yourself?
We Respond to everyday stresses the same way as our ancestors would to life threatening ones. However nowadays we may be killing our selves over an overdue assignment, or a list of chores to complete, whereas ancient humans would be more concerned over finding food and escaping dangers: actual life/death scenarios. Stress is usually described by the fight or flight response, which aims to prepare an animal for action, such as runnig from a predator. This is mediated by the hormone epinephrine, known more commonly as adrenaline. It leads to increased sugars in the blood and increased pumping of the heart, ready for increased activity.
Stresses are related to the hypothalamus, either via the limbic system, which relays emotional stresses, or by the brain stem linked to physical stress. The key point here is that whatever the cause of stress, our bodies produce the same response. The hypothalamus stimulation leads to production of CRH (corticotropin releasing hormone) to initiate the fight or flight response and the release of ACTH from the pancreas to activate the adrenal gland.
Cortisol released from the adrenal gland will then break down molecules (catabolisism) of our body tissues, which can be converted to fuels for the body. Chronic stress increases plasma cortisol and can reduce numbers of dendritic branches and neurones in our brain, sometimes causing temporary reductions in spatial memory . So perhaps revising too hard for an exam could have the opposite to the intended effect and make it more difficult to remember?
In addition, since cortisol aids the breakdown of tissues for energy substrates, long term release of the hormone could lead to weakening of bodily structures like bones and muscles, or major weight loss. You may find that being constantly worried and on edge can make you feel weak and often fatigued. This itself suggests that completing the task at hand will become more difficult and may make your problems worse.
Under stress, you are also more likely to have impaired immune system. You may have noticed an increase in number of sniffs and coughs over the past weeks in the library or just passing you in the street. Stress mediators can pass the barrier from your blood into the brain and exert their effects there, often in the neuroendocrine system, which leads to inhibition of lymphocytes and macrophages, your white blood cells.
In addition to this are many other minor effects from stress, dependent on its longevity and intensity. It can affect the response of your brain and make it less sensitive over time. It can affect appetite, the structure of your hippocampus (in the brain) and can cause neurogenesis disorders.
So, overall, it appears that while short term stress may give us the burst of energy or motivation we need, stressing constantly over a long period of time can begin to severely impact our health. So take that break, go for that pint, spend time with your friends, and take it easy. You’re not a caveman whose survival literally depends on completing your chores for the day. It’s time to stress less.