Cortisol, also known as the stress hormone, meets adaptive functions in our body. In the face of a danger to life, this hormone is the primary helpful molecule to react quickly.
However, for various reasons, your body can produce excess cortisol, even in the absence of an obvious threat. When this occurs, chronically high levels of cortisol are capable of causing negative changes and causing damage that disrupts essential functions of our body.
Read on to learn how cortisol affects each part of our body and why it affects many differently.
Effects of cortisol and stress on the body
When faced with a threat, your hypothalamus, a small region at the base of your brain, activates an alarm system in your body. Through a combination of nerve and hormonal signals, this system causes the adrenal glands located above the kidneys to release a surge of hormones, including adrenaline and cortisol.
Adrenaline increases your heart rate, raises your blood pressure, and increases your energy supply. Cortisol, the primary stress hormone, increases sugars (glucose) in the bloodstream, improves glucose use in the brain, and increases the availability of substances that repair tissues.
Cortisol mobilizes essential resources in our body, but it also slows down functions that would be nonessential or harmful in a fight or flight situation.
This complex natural alarm system also communicates with brain regions that control mood, motivation, and fear. Now let’s take a closer look at what cortisol does in every system of your body.
- Immune system
Stress boosts the immune system, which can be advantageous for immediate situations. This stimulation can help you avoid infection and heal wounds.
But over time, stress hormones will weaken your immune system and reduce your body’s response to foreign invaders. For this reason, people under chronic stress are more susceptible to viral illnesses such as the common flu, among other infections.
- Reproductive system
It is not unusual to lose your desire when under constant stress. While short-term cortisol can cause men to produce more of the male hormone testosterone, this effect does not last.
If stress continues for a long time, a man’s testosterone levels can start to drop. This can interfere with sperm production and cause erectile dysfunction or impotence. Chronic stress can also increase the risk of infection of male reproductive organs such as the prostate and testicles.
For women, stress can affect the menstrual cycle. It can cause irregular, heavier, or more painful periods. Chronic stress can also magnify the physical symptoms of menopause.
- Respiratory system
Cortisol affects your respiratory and cardiovascular systems. During the stress response, you breathe faster to distribute oxygen-rich blood to your body quickly. Stress can make breathing even more difficult if you already have a breathing problem like asthma or emphysema.
- Cardiovascular system
Under stress, your heart also beats faster. Stress hormones cause your blood vessels to contract and divert more oxygen to your muscles, so you will have more power to act. But this also raises your blood pressure. When your blood pressure rises, your risk of stroke or heart attack also increases.
- Digestive system
The rush of hormones, rapid breathing, and increased heart rate can also upset your digestive system. You are more likely to have heartburn or acid reflux due to increased heartburn. Stress does not cause ulcers, but it can increase your risk of getting ulcers and cause existing ulcers to react.
Stress can also affect how food moves through your body, causing diarrhea or constipation. You may also experience nausea, vomiting, or stomach pain.
Also, your liver produces extra blood sugar (glucose) to give you an energy boost under stress. If you are under chronic stress, your body may not be able to handle this extra glucose surge. High cortisol can increase your risk of developing type 2 diabetes.
- Muscular system
Your muscles tighten to protect yourself from injury when you are stressed. Tight muscles cause headaches, back and shoulder pain, and body aches. Over time, this can trigger an unhealthy cycle and cause complications in the body.
When cortisol spikes
The body’s stress response system is often self-limited. Once a perceived threat has passed, hormone levels return to normal. As adrenaline and cortisol levels drop, heart rate and blood pressure return to baseline, and other systems resume normal activities.
However, when stressors are always present and you constantly feel under attack, that fight or flight reaction remains active.
Long-term activation of the stress response system and overexposure to cortisol and other hormones can disrupt almost every process in your body. This puts you at higher risk for many health problems, including:
- Digestive problems
- Heart disease
- Sleep disorders
- Weight gain
- Impaired memory and concentration
Why do some people stress more than others?
Your reaction to a potentially stressful event is different from anyone else. How you react to stressors is affected by factors such as:
- Genetics. The genes that control the stress response keep most people on a reasonably stable emotional level and only occasionally prepare the body to fight or flight. Excessive cortisol responses may be due to slight differences in these genes.
- Experience. Sometimes strong stress reactions can be attributed to traumatic events. People who were neglected or abused as children tend to be particularly vulnerable to stress. The same goes for people who have suffered violent crimes, military personnel, police officers, and firefighters.
You may have some friends who seem relaxed about almost everything and others who react strongly to less stress. Most people respond to life stressors somewhere in between those two extremes.