Understanding Cortisol and the Fight-or-Flight Response

What is Cortisol?

Cortisol is a steroid hormone produced bythe adrenal glands, which are located on top of each kidney. It plays a crucialrole in the body's response to stress and is often referred to as the"stress hormone." However, cortisol has many other importantfunctions, including:

1. Regulating Metabolism: Cortisol helpscontrol how the body uses carbohydrates, fats, and proteins. It influencesblood sugar levels and can affect weight gain or loss.

2. Reducing Inflammation: Cortisol hasanti-inflammatory properties, making it essential for regulating the immunesystem's response to injuries or infections.

3. Assisting with Memory Formulation:Cortisol affects the formation of memories and can influence cognitivefunction.

4. Controlling Salt and Water Balance: Ithelps regulate blood pressure by controlling the balance of salt and water inthe body.

5. Supporting the Circadian Rhythm:Cortisol levels fluctuate throughout the day, peaking in the morning andgradually decreasing throughout the day. This helps regulate sleep-wake cycles.

The Fight-or-Flight Response

The fight-or-flight response is anautomatic physiological reaction to an event perceived as stressful orfrightening. The response is triggered by the sympathetic nervous system,preparing the body to either fight the threat or flee from it.  The analogy we use at StrIVeMD Wellness andKetamine is being in a room with a polar bear. This response involves severalkey processes:

1. Perception of Threat: When the brainperceives a threat, the hypothalamus activates the sympathetic nervoussystem.  

2. Release of Adrenaline and Noradrenaline:The adrenal glands release adrenaline (epinephrine) and noradrenaline(norepinephrine) into the bloodstream. These hormones increase heart rate,blood pressure, and energy supplies.

3. Release of Cortisol: The hypothalamusalso triggers the release of corticotropin-releasing hormone (CRH), whichstimulates the pituitary gland to release adrenocorticotropic hormone (ACTH).ACTH then prompts the adrenal glands to produce and release cortisol.

4. Physiological Changes:

  -Increased Heart Rate and Blood Pressure: This ensures that more oxygen andnutrients are delivered to vital organs and muscles.

  -Dilated Pupils: This improves vision, allowing the individual to better assessthe threat.

  -Redistribution of Blood Flow: Blood is redirected away from non-essentialfunctions, such as digestion, and towards the muscles and brain.

  -Release of Glucose: The liver releases glucose into the bloodstream to providea quick source of energy.

These changes prepare the body to eitherconfront the threat (fight) or escape from it (flight).

Role of Cortisol in the Fight-or-FlightResponse

Cortisol plays a critical role insustaining the fight-or-flight response. While adrenaline and noradrenalineprepare the body for immediate action, cortisol helps maintain the responseover a longer period. Here’s how cortisol contributes:

1. Prolonging the Stress Response: Cortisolensures that the body remains alert and prepared to handle the threat. It helpssustain the energy supply by promoting the release of glucose and increasingthe availability of substances needed for tissue repair.

2. Modulating Immune Response: Whilecortisol’s anti-inflammatory effects are crucial for preventing overreaction toinjury or infection, they can also suppress the immune system if cortisollevels remain high for too long. This modulation helps prioritize immediatesurvival over long-term health.

3. Affecting Mood and Cognition: Elevatedcortisol levels can influence mood and cognitive function, making individualsmore alert and focused. However, chronic high levels of cortisol can lead toanxiety, depression, and cognitive impairments.

Chronic Stress and Cortisol

While the fight-or-flight response isessential for survival, chronic activation of this response due to ongoingstress can lead to numerous health issues. Prolonged high levels of cortisolcan contribute to:

1. Mental Health Issues: Chronic stress andelevated cortisol are linked to anxiety, depression, and other mental healthdisorders.

2. Cardiovascular Problems: Long-term highcortisol levels can lead to hypertension, increased risk of heart disease, andother cardiovascular issues.

3. Metabolic Disorders: Persistent cortisolelevation can lead to weight gain, particularly around the abdomen, andincrease the risk of type 2 diabetes.

4. Weakened Immune System: Continuous highcortisol levels can suppress the immune system, making individuals moresusceptible to infections and slowing down the healing process.

5. Cognitive Impairments: Chronic stresscan affect memory and cognitive function, potentially leading to difficultieswith learning and concentration.

Managing Cortisol Levels

Managing stress is crucial for maintaininghealthy cortisol levels and overall well-being. Here are some strategies tohelp manage stress and cortisol levels:

1. Regular Exercise: Physical activityhelps reduce cortisol levels and improve mood through the release ofendorphins.  However, high intensityexercise can lead to higher cortisol levels, so exercise in moderation.

2. Healthy Diet: Eating a balanced dietrich in fruits, vegetables, lean proteins, and whole grains supports overallhealth and can help regulate cortisol levels. Ultraprocessed foods and simple sugars are inflammatory and can worsensystemic inflammation from chronic elevated cortisol.  Supplements such as Rhodioloa, Ashwaganda,and Magnesium can help lower stress and cortisol as well.

3. Adequate Sleep: Quality sleep of atleast 7 hours is essential for maintaining healthy cortisol levels and allowingthe body to recover from daily stress.

4. Mindfulness and Relaxation Techniques:Practices such as meditation, deep breathing, and yoga can help reduce stressand lower cortisol levels.  Apps such asHeadspace, Calm, and 1 Giant Mind can be very helpful to those who have troublewith meditation (like I do).

5. Social Support: Maintaining strongsocial connections and seeking support from friends, family, or support groupscan help buffer against stress.

6. Professional Help: If stress becomesoverwhelming, seeking help from a mental health professional can providestrategies and support for managing stress and reducing cortisol levels.

7. Ketamine and Stellate Ganglionblock.  See last week’s blog about howthese two treatment options can lower cortisol.


Cortisol and the fight-or-flight responseare essential components of the body’s stress management system. While thesemechanisms are crucial for short-term survival, chronic stress and elevatedcortisol levels can lead to significant health problems. Understanding howcortisol works and learning strategies to manage stress can help maintain ahealthy balance, promoting better mental and physical health.