Cortisol & Stress - It’s Not All Bad.

 

Cortisol & Stress - It’s Not All Bad.

Stress is “a physical, chemical, or emotional factor that causes bodily or mental tension and may be a factor in disease causation”. (Merriam-Webster)

What triggers the organism is known as a stressor. A stressor can come in many forms. It can be actual or perceived. Cutting your leg would be a physical stressor (direct damage) and also an internal (chemical) stressor. The body needs to act on containing blood/nutrient loss and healing itself, protecting the body from unwanted exposure. A stressor may also be psychosocial, relating to unusual amounts of stress due to environmental or social factors (work life, finances, divorce).

Not all stress is bad! Many of these stressors function to keep us within a very narrow and optimal range of conditions. The stomach causes discomfort to gain nutrients from food. The urge to urinate triggers the removal of toxins. Pain from burning your finger causes you to be more cautious around fire. Learning something new causes stress but it’s an essential process!

Acute stress is short-term stress. Think of the sudden bang of a firework or a heavy work week. These stressors are usually tolerable and can be managed with minimal side effects. Then we have chronic stress, which is long-term stress. This type of stress can lead to negative physical and emotional effects. For example, studies in humans show early life stress is associated with the development of social anxiety, aggression, and antisocial behavior in adolescents and adults.

Our goal should be to minimize chronic stress while managing acute stress. Stress can be unavoidable! This is where good environmental arrangements come into play!

Cortisol (a glucocorticoid) fights inflammation, regulates metabolism, regulates the immune system, and has effects on learning and memory. It follows a circadian rhythm, peaking in the morning as we wake, decreasing throughout the day. Waking up is “stressful”, meaning it increases the demands required from your body. Cortisol isn’t stress itself, it’s the one establishing balance against the stressors.

Cortisol is released as a hormone by the adrenal cortex (just above your kidneys). This is achieved via the Hypothalamic-Pituitary-Adrenal (HPA) axis. Cortisol then travels throughout the bloodstream where it can have its effects including influencing metabolism, immune function, and stress response regulation.

A state of allostasis is where the body is meeting the current demands of the recent environmental change (waking up, working out, psychological, etc). This maintains a real-time “balance” of your bodily systems. This includes the release of several neurotransmitters, hormones, sugars, and more.

Chronic stress is the body’s inability to maintain allostasis, which can present with digestive problems, heart disease, weight gain, sleep problems, and damage to the brain resulting in memory or concentration problems. It can also make managing stress in the future more difficult.

When the stressor subsides, cortisol release remains active for several hours. Once a certain threshold is met, your body uses a negative feedback system to terminate the release of corticotropin-releasing factor — CRF which then downstream, stops the release of adrenocorticotropic hormone — ACTH, which is responsible for releasing epinephrine (and others) used in that “fight-or-flight” response.

A core function of cortisol is to increase glucose (sugar) levels in your body for a quick energy source. Cortisol also “shuts down” your parasympathetic and immune system, conserving energy for more immediate matters. Cortisol has been demonstrated to lessen the receptivity of pain!

You can see that it’s not cortisol, or even “stress”, that’s bad. But it's how intense, long, and under what conditions that matter. This is another reason it’s important to work at your dog’s unique pace!

—

Image by brgfx on Freepik