Begin: 12/2/2024
Finish: 2/17/2024
Title: Stress and Your Body Part 1
Instructor: Professor Robert Sapolsky
Stanford University
Why I choose to take this class:
To learn more about everyday stress and how it affects our body. Know about what the causes of stress and how to manage stress to avoid stress related illness.
What I learned from this class:
Why don’t Zebras get ulcers? Why do we?
Animals do not experience some issues which human experience i.e.. traffic jam, global warming, etc… We do and that’s the critical point of the whole field of stress and disease. We turn on the exact same stress-response as do those animals running for their lives or running for a meal, and we turn it on for psychological reasons. When you are running for your life, you have been knocked out of Homeostatic balance. Short physical crisis leads to stress-response. You secrete adrenalin and other hormones to reestablish homeostasis. However, modern human worry about physiological states. We worry about our body slowly being done by things like heart disease, diabetes, strokes ….. Westernized disease these days has a lot to do with our social status and psychological makeup. When you look at the diseases that make us sick these days, those diseases of slow accumulation over time, they are predominantly diseases that are sensitive to stress. We human activate the stress-response for reasons of psychological factors and that is not what are system evolved for. If you do that chronically, you are going to get sick. The problem is that after a while, your stress-response is more damaging than the stressor itself, especially if the stressor was some psychological nonsense you made up. When you chronically turn on the stress-response, your body is forced to ignore the repair and growth functions and take care of the stressor.
The Nuts and Bolts of the Stress-response:
The human stress-response: there are two systems responsible for it – First there the Nervous system: the second is the release of hormonal messengers. Part of the Nervous system which you don’t have control over – the Autonomic Nervous system. The Autonomic system comes in two part: The first part is the Sympathetic Nervous System : Controls stress-response: In contrast the second part is the Parasympathetic Nervous System : mediates, calm, vegetative functioning. The Nervous system is controlled by the Hypothalamus in the brain stem area – does regulatory stuff. The second layers is the Limbic System which controls: emotions, lust, rage, petulance and on top layer is the cortex which process: reasoning, processing and long term memory. The second type of regulation is by was of hormones: which is a chemical messenger from a brain cell or from cells throughout the body. The brain releases hormones that tell the pituitary glands what hormones to release. During stress-response Epinephrine (Adrenalin), another steroid hormone is Glucocorticoids and other hormones. Hormones whose secretions is inhibited during stress are: growth hormones, Insulin, repairs and reproductive hormones.
Stress and Your Heart:
During stress-response, you secrete Glucocorticoids and Epinephrine, you turn on the Sympathetic Nervous Nervous System and turn off the Parasympathetic System. You heart rate and blood pressure goes up. Your body is sending blood, oxygen, glucose to body part that needs it, like legs, muscles and lungs. Meanwhile divert blood away from parts of the body that don’t need it, such as your gut and reproductive system. If you increase your blood pressure chronically, you are suffering from hypertension. Couple hypertension with a high fat diet, you get more vascular damage. Once the coronary vessels are damaged, when you increase blood flow during stress, it no longer vasodilate they constrict instead, resulting in Myocardial Ischemia. Your heart muscles are not getting enough of the stuff they need.
Stress, Metabolism, and Liquidating your assets:
You secrete insulin in response to elevated levels in your blood stream, or even in anticipation of a meal. Along comes an acute stressor. You need energy not to store away but to power your muscles to save your life. You secrete Glucocorticoids, Glucagon and Epinephrine and shut down Insulin secretion, so you are not storing anything. For juvenile Type 1 Diabetes, each time you get stressed, you are releasing sugar into your bloodstream and then storing it away. Getting huge spikes making Glycemic control difficult. Type 2 Diabetes, the problem is not too little Insulin, it is an excess of nutrients. When you are overweight or obese, your fat cells are full, your brain signals the fat cell storage sites to ignore and become resistant to it, and you lose your sensitivity to it. Insulin resistant can lead to Metabolic Syndrome.
Stress, Overeating and your Digestive Tract:
Your brain on the onset of a stress secretes a Hypothalamic hormone that causes the pituitary to secrete a hormone that stimulate the Adrenals to release Glucocorticoids. Glucocorticoids stimulate appetite to replace all the energy depleted. After the stress, it takes a few minutes for Glucocorticoid levels to go back to normal. Thus after the stressor, there is a period of increased appetite. All the excess fat go into your fat cells: abdominal fat around the waist and gluteal fat in the buttock. Abdominal fat is more dangerous and can lead to: Fatty liver, release inflammatory signals, puts more stress on your body.
Stress and growth: From the Womb:
You don’t want to be a stress fetus. There are 2 realms of consequences of fetal stress: The first is at birth, more fetal stress equals a lower body weight. The Other is what sort of adult body you are going to have as you respond to adult environments. Like problems learning and memory and prone to anxiety.
Stress and Growth and Child Development:
If you are a young person and are chronically stressed, you are not going to grow as fast, because of elevated Glucocorticoids, elevated activation of the Sympathetic Nervous System and decreased secretion of growth hormones. The cardio-vascular stress response, your blood pressure goes up to deliver energy to muscles but decrease blood delivery to unessential areas like your gut. If you are a kid and chronically decreasing blood flow to your guts, you are not absorbing nutrient as readily. Removing that child from stressful setting and everything gets better.
Stress and Female Reproduction:
Stress in female delay puberty and negatively impact reproduction. Starvation can shut down ovulation. This is due to depletion of fat. Similarly long distance runners and athletes, see their fat deposits dip below the threshold where they begin to have ovulatory problems. In Vitro Fertilization (IVF) is a stressful process which makes IVF less likely to be successful. After you have gotten pregnant to start, chronic stress can cause a miscarriage, because of the decrease blood flow to the fetus. If that happens enough, it increase the likelihood of a miscarriage. Chronic stress decrease your libido due to reduction of reproduction-related hormones, and sensitivity in those areas are blunted. Sex tends to release Dopamine, during chronic stress, Dopamine is reduced and sex is less pleasurable.
Stress and The Male Reproduction:
Stress reduces the Testosterone levels in men. the problem during stress is not that Testosterone levels go down, the problem is Erectile Dysfunction. What happen during stress: you cannot turn on the Parasympathetic Nervous System, so you have the problem of stress induced impotency or you get anxious and accelerate the transition from Parasympathetic to the Sympathetic Nervous System: leading to Premature Ejaculation. Stress, physical or psychological can shut down the male reproduction system.
Stress and The Immune System:
The immune system protects you from pathogens. There are 2 categories of immune cells or lymphocytes: T cells originate from the Thymus and B cells which originate in the bone marrow. What happens during stress and the short-term effect on immunity. These are diseases that cause your immune system to decide what part of you system is normal and should be there, are in fact some invasive pathogens. Onset of stressors, where you activate the immune system over and over , you increase the immune system over activating into autoimmunity. So there is a relationship between chronic stress and flare ups of autoimmune disease. The Glucocorticoids tries to bring the immune system back to baseline, but with repeated stress, the immune system is suppressed to below where it normally is, leading to immunosuppression.
Stress and Pain:
Pain constitute a stressor and stress can cause you to change your sensitivity to pain. Major stress, sustained stimulations of pain pathways make them more sensitive and more responsive, so leading to Hyperalgesia – more pain. Your depleted Beta-Endorphin, the hormone that protects you from the stressor, the pain comes back and keeps going.
How will this class contribute to my success upon release:
The information acquired from stress and its effect on our body has made me aware of how external and internal psychological forces can induce stress. During my time being incarcerated, this class has helped me managed, control my stress, live a calmer and more peaceful life. This information will be shared with my family and communities when I volunteer my services through teaching, tutoring and mentoring.
