Science of Stress
Understand Why Chronic Stress is harmful ?
Dear Readers,
This article will explore the Science of Stress! We will focus on the questions: Why we Stress? What happens when we Stress and How an adaptive life-saving response becomes a cause and potential amplifier for life devastating diseases? In the follow-up article, I will share Science-backed Stress Management ToolKit which can be easily assimilated into lifestyle.
"Stress is the spice of life. We need a certain amount of stress to remain healthy, and to stay motivated and challenged. It's when stress becomes chronic or uncontrollable that it wreaks havoc on our health." - Bruce McEwen
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Evolution of Diseases Over Time
Let’s understand the evolution of diseases over time – this will help you understand the broad concept why we should pay more attention to stress?
100 years ago, the diseases which were killing us were related to infections either viral, bacterial, parasitic or due to poor hygiene (like Child Birth, Influenza, Plague, Small Pox, Yellow Fever, Pneumonia, Tuberculosis, Diarrhea, Leprosy).
Thanks to the revolutionary advances in medicine and public health, our patterns of disease have changed. Now, we die of totally bizarre diseases that never used to exist in this planet, diseases like heart failure, diabetes, hypertension. etc. This is a very novel realm we’ve entered in terms of making sense of which of us are sick and which are healthy.
Diseases of slow accumulation of damage from lifestyle over time like obesity, hypertension, atherosclerosis, diabetes are predominantly can be caused by or made worse by stress!!
Mind-Body Interactions
There has been a revolution in medicine concerning how we think about the diseases that now afflict us. It involves recognizing interactions between body and the mind, the ways in which emotions and personality can have tremendous impact on the functioning and health of virtually every cells in the body.
It is about the role of stress in making some of us vulnerable to diseases, the ways some of us cope with stressors, and the critical notion that you cannot really understand a disease in vacuo, but rather only in the context of the person suffering from that disease.
What is Stress ?
Now lets understand stress…
For animals like zebras, the most upsetting things in life are acute physical crises. You are a zebra, a lion has just leapt out and ripped your stomach open, you’ve managed to get away, and now you have to spend the next hour evading the lion as it continues to stalk you. Or perhaps just as stressfully you are that lion, half starved and you had better be able to sprint across the savanna at the top speed and grab something to eat or you won’t survive, these are extremely stressful events and they demand immediate physiological adaptations if you are going to live.
There is another category social and phycological disruptions. Essentially we humans live well enough and are smart enough to generate all sorts of stressful events purely in our heads. Viewed from the perspective of the evolution of the animal kingdom sustained phycological stress is a recent invention, mostly limited to humans and other social primates. We can experience wildly strong emotions linked to mere thoughts.
A large body of evidence suggests that stress-related disease emerge, predominantly, out of the fact that we do often activate a physiological system that has evolved for responding to emergencies, but we turn it on for months on end, worrying about mortgages, relationships, and promotions.
What is Stress-Response ?
To understand stress you need to know homeostasis! Hopefully you have heard me explaining this before, it is one of the cool concepts of our physiology!! OK if you forgot the concept of homeostasis….don’t stress…it is the idea that the body has an ideal level of oxygen, an ideal degree of temp and so on. All these variables are maintained in a balance, the state in which all sorts of physiological measures are being kept at optimum level.
Anything in the outside world that knocks you out of homeostatic balance is a stressor and the stress-response is what your body does to reestablish homeostasis.
A stressor can also be anticipation of that happening.
"There is no such thing as an inherently stressful situation. Stress is not a quality of the environment, nor is it a quality of an individual. Stress is a transaction between the two." - Robert Sapolsky
For 99% beasts on this planet stress is 3 mins of scream response but not for us. For us humans we think and can start the stress response. Our human experience is replete with psychological stressors, a far cry from the physical world of hunger, injury, blood loss or temp extremes.
It is this generality of the stress response that is the most surprising!!
Stressors
Stress is highly personal because we have to interpret a situation as stressful. Although what stresses you is surely different from what stresses others. However, there are common elements to situations that stress everyone. In fact, there is a universal recipe for stress.. N.U.T.S.!
What Your Body Does to Adapt to a Stressor ?
When you experience stress or think about one your body stops all long term projects and concentrate on present to mitigate the problem at hand. This response is called Flight-Fight response.
Rapid mobilization of energy from the storage sites and the inhibition of further storage
Heart Rate, BP and Breathing increase, all to transport nutrients and oxygen at greater rates
Body halts long term, expensive building projects.
Digestion is inhibited
Same goes for growth, reproduction, both expensive, optimistic things to be doing with your body. Tissue repair decreased
Immunity is inhibited
Perception of pain is blunted
The principal way in which your brain can tell the rest of the body what to do is to send messages through the nerves that branch from your brain down your spine and out to the periphery of your body.
One half of the system is activated in response to stress, the other half is suppressed. The half that is activated by stressors is called Sympathetic Nervous System.
Originating in the brain, sympathetic projections exit your spine and branch out to nearly every organ, every blood vessel and every sweat gland in your body. They even project to tiny little muscles attached to hairs on your body. This nervous system kicks into action during emergencies or when we think are emergencies. It helps mediate vigilance, arousal, activation, mobilization.
In case of females besides flight-or-flight response another response is activated - ‘Tend and Befriend’. Tending involves nurturant activities designed to protect the self and offspring that promotes safety and reduce stress; befriending is the creation and maintenance of social networks that may aid in this process. This response is dominated by oxytocin hormone in conjugation with female reproductive hormones and stress hormones.
Hormones of the Stress response
Sympathetic nerve endings also release Adrenaline and also closely related substance called Noradrenaline. Adrenaline is secreted as a result of the actions of the sympathetic nerve endings in your adrenal glands located just above kidneys. Noradrenaline is secreted by all other sympathetic nerve endings throughout the body.
As the master gland, the brain can think or experience something stressful and activate components of the stress-response hormonally. Some of the hypothalamus-pituitary-peripheral glands links are activated during stress, some inhibited.
Besides adrenaline and noradrenaline, another important class of hormones which are released as a result of stress are called Glucocorticoids. Adrenaline acts within seconds, glucocorticoids back this activity over the course of minutes or hours.
Long-Term Effects of Stress
If you constantly mobilize energy at the cost of energy storage, you will never store any surplus energy. You will fatigue more rapidly, and your risk of developing a form of diabetes will even increase. The consequences of chronically activating your cardiovascular system are similarly damaging: if your blood pressure rises to 180/100 when you are sprinting away from a lion, you are being adaptive, but if it is 180/100" everytime you see a mess in your teenager’s bedroom, you could be heading for a cardiovascular disaster. If you constantly turn off long-term building projects, nothing is ever repaired.
How stress can lead to cardiovascular problems like heart attacks and strokes. Let’s explore this in little detail-
It's important to note that not everyone who experiences stress will develop cardiovascular problems. However, chronic stress can increase the risk of these issues, especially in combination with other risk factors, such as genetics, poor diet, and lack of exercise.
Too much stress leads to sympathetic overdrive, which is harmful!
Stay-tuned for the follow-up article which will delineate science-backed tips and tools to manage stress and help you to live a happy and healthy life.