Everything You Need to Know About Cortisol: How to Manage This Stress Hormone to Improve Your Health

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Cortisol, often called the "stress hormone", plays a vital role in our body, but an imbalance in this hormone can have serious health effects. Too high or too low levels of cortisol can lead to symptoms such as fatigue, weight gain, and sleep disorders. Understanding the link between cortisol, stress, and exercise is crucial for maintaining optimal hormonal balance. In this article, find out how stress management, nutrition, and physical activity can naturally help regulate your cortisol levels. Also learn how to recognize the signs of an imbalance and what solutions exist to address it. An essential guide to optimize your daily well-being.

TABLE OF CONTENTS

WHAT IS CORTISOL?

Cortisol is a steroid hormone naturally produced by the adrenal glands, located above the kidneys. It plays a vital role in the proper functioning of the body, particularly in response to stress—hence its nickname: the stress hormone.

What is the role of cortisol in the body?

Cortisol is involved in many physiological processes:

  • It regulates metabolism by facilitating the conversion of fats, carbohydrates, and proteins into energy.
  • It helps maintain stable blood sugar levels, especially during fasting or stress.
  • It acts as a natural anti-inflammatory by controlling certain immune responses.
  • It contributes to maintaining stable blood pressure.
  • It also influences the sleep-wake cycle, with a secretion peak in the morning to help the body wake up.

In short, cortisol is essential for our daily balance.

Is cortisol a good or bad hormone?

Cortisol is not a bad hormone in itself. In fact, it is vital for survival. The problem arises when its level remains chronically high, such as during prolonged stress, burnout, or sleep disorders. This hormonal imbalance can lead to:

  • Persistent fatigue
  • Weight gain, especially around the abdomen
  • Sleep difficulties
  • Irritability, anxiety
  • Weakened immune system

On the other hand, a lack of cortisol (as in Addison’s disease) can also have serious consequences: low blood pressure, muscle weakness, and even life-threatening situations.

In summary, cortisol is a good hormone—as long as it's in balance.

What is the difference between cortisol and adrenaline?

Cortisol and adrenaline are both stress hormones, but they have different functions and mechanisms:

CortisolAdrenaline
1Steroid hormoneHormone (and neurotransmitter)
2Secreted by the adrenal glands (cortex)Secreted by the adrenal glands (medulla)
3Long-term stress responseImmediate stress response
4Increases blood sugar, modulates inflammationSpeeds up heart rate, dilates pupils, boosts alertness
5Slower but longer-lasting actionFast but short-lived action

Adrenaline triggers the well-known "fight or flight" response, while cortisol helps the body adapt more sustainably to a stressful situation.

WHAT ARE THE SYMPTOMS OF HIGH CORTISOL LEVELS?

High cortisol levels, also known as hypercortisolism, can have significant effects on both physical and mental health. This hormonal imbalance is often linked to chronic stress but can also result from specific medical conditions such as Cushing’s syndrome.

How to recognize abnormally high cortisol levels?

The diagnosis of excess cortisol is based on laboratory tests (blood, saliva, or urine), but some typical symptoms can be warning signs:

  • Persistent fatigue, even after a restful night.
  • Difficulty relaxing or mentally disconnecting.
  • Increased heart rate or palpitations.
  • Feeling “on edge.”
  • Sleep disturbances (frequent nighttime awakenings, insomnia).
  • Increased cravings for sweet or fatty foods.
  • Loss of muscle mass despite exercising.
  • Weakened immune system: frequent infections, slow healing.

One or two isolated signs aren’t enough to draw conclusions, but a combination of several may reflect abnormally high cortisol levels.

What are the signs of chronic stress related to cortisol?

Chronic stress pushes the body to produce cortisol continuously, eventually disrupting overall balance. Typical signs of this prolonged imbalance include:

  • Irritability, anxiety, even panic attacks
  • Decreased concentration and memory problems
  • Frequent headaches
  • Digestive issues: bloating, constipation, abdominal pain
  • Disrupted hormonal cycles (in women: irregular or absent periods)
  • Reduced libido
  • Mental exhaustion or a feeling of burnout

This type of stress becomes problematic when it persists, impacting daily performance, social relationships, and overall health.

Can high cortisol cause weight gain?

Yes, excess cortisol can promote weight gain, especially around the abdominal area. Several mechanisms are involved:

  1. 1. Increased appetite: Cortisol stimulates hunger, particularly for sugary or fatty foods.
  2. 2. Fat storage: Cortisol directs fat storage toward the abdominal area, even in lean individuals.
  3. 3. Insulin resistance: High cortisol levels disrupt blood sugar regulation, which can lead to fat storage.
  4. 4. Loss of muscle mass: Excess cortisol can lead to muscle tissue breakdown, slowing down the basal metabolic rate.

This weight gain is often difficult to reverse without a comprehensive approach that includes stress management, a proper diet, and regular physical activity.

WHAT ARE THE EFFECTS OF LOW CORTISOL LEVELS?

Low cortisol levels, also known as hypocortisolism, can have serious health consequences. Since this hormone is essential for the balance of many vital functions, a deficiency can lead to a general weakening of the body, both physically and mentally.

What happens when you lack cortisol?

A lack of cortisol can cause a series of persistent symptoms, which may be hard to identify at first. The most common signs include:

  • Severe fatigue, often described as overwhelming or disabling
  • Muscle weakness
  • Dizziness, especially when standing up (orthostatic hypotension)
  • Loss of appetite and unexplained weight loss
  • Nausea, vomiting, or abdominal pain
  • Decreased concentration and memory issues
  • Irritability, depressed mood
  • Increased sensitivity to stress

In severe cases, cortisol deficiency can lead to an adrenal crisis—a medical emergency requiring immediate treatment.

What causes low cortisol levels?

Low cortisol can be due to various causes, whether medical or functional in origin:

  1. 1. Addison’s disease: a rare condition where the adrenal glands no longer produce enough cortisol (and sometimes aldosterone).
  2. 2. Secondary adrenal insufficiency: caused by dysfunction of the pituitary gland (which regulates cortisol production).
  3. 3. Sudden discontinuation of corticosteroid treatment: this can suppress natural cortisol production.
  4. 4. Exhausting chronic stress: over time, overload can lead to hormonal collapse (adrenal fatigue, though this term is controversial in medicine).
  5. 5. Malnutrition or very restrictive dieting: can weaken overall hormonal function.

Hormone testing can confirm a deficiency and help identify the exact cause.

Can cortisol deficiency cause chronic fatigue?

Yes, a cortisol deficiency is a possible cause of chronic fatigue. Cortisol plays a key role in regulating energy, blood pressure, and the stress response. When this hormone is produced in insufficient amounts, the body struggles to meet daily demands. This results in persistent fatigue that doesn’t improve with rest.

It is important to note that not all chronic fatigue is related to cortisol, but when it is accompanied by other symptoms (low blood pressure, digestive issues, weight loss, etc.), a hormonal assessment can be useful to guide the diagnosis.

HOW TO MEASURE YOUR CORTISOL LEVELS?

Measuring cortisol levels helps assess the body’s hormonal balance and identify a potential excess or deficiency that could be behind persistent symptoms such as fatigue, anxiety, sleep disorders, or weight gain. There are several testing methods, and some are more reliable than others depending on the clinical context.

What is the most reliable method to test cortisol?

Cortisol can be measured using different types of samples:

  • Blood: This is the most commonly used and most reliable method for a single-time evaluation of cortisol levels. It provides an accurate measurement at a specific time of day.
  • Saliva: Mainly used to monitor cortisol fluctuations throughout the day (daily profile), or for Cushing’s syndrome screening (especially using a nighttime saliva test).
  • 24-hour urine collection: This method evaluates the total amount of free cortisol excreted in a full day, useful when chronic overproduction is suspected.

The choice of method depends on the symptoms being investigated and the medical context. In clinical practice, blood testing remains the most accessible and standardized option.

When should you get a blood test to measure cortisol?

Cortisol levels fluctuate throughout the day. They peak in the morning, typically between 6 AM and 8 AM, and gradually decline to their lowest levels at night. Therefore, it is recommended to perform the blood test:

  • Early in the morning, ideally between 7 AM and 9 AM, for reliable result interpretation.
  • On an empty stomach, if possible, since stress from food intake or recent physical activity can affect the reading.
  • While avoiding periods of acute stress (illness, emotional shock), as these can temporarily elevate cortisol levels.

In specific cases, a doctor may prescribe a dexamethasone suppression test to observe the adrenal glands’ response and refine the diagnosis.

What is considered a normal cortisol level in the bloodstream?

Normal cortisol blood values vary depending on the time of the sample and the lab, but in general:

  • Morning (7 AM – 9 AM): between 140 and 700 nmol/L (or 5 to 25 µg/dL)
  • Evening (around 8 PM): between 50 and 280 nmol/L (or 2 to 10 µg/dL)

These numbers may vary slightly depending on the units used (nmol/L or µg/dL) and the testing methods. That’s why it’s essential to interpret the results with a healthcare professional, who will consider the clinical context and any ongoing treatments.

HOW TO NATURALLY REDUCE YOUR CORTISOL LEVELS?

When stress becomes chronic, cortisol levels can remain elevated for extended periods, disrupting hormonal balance, sleep, mood, and metabolism. Fortunately, several natural approaches can help bring cortisol levels back to a healthier range without medication.

Which foods help lower cortisol?

The quality of your diet directly influences hormonal balance. Certain foods help lower cortisol by providing nutrients that support the nervous system and adrenal glands:

  • Fruits rich in vitamin C (kiwi, citrus fruits, strawberries): vitamin C is known to limit excessive cortisol secretion.
  • Leafy green vegetables (spinach, kale): rich in magnesium, a mineral that helps reduce the stress response.
  • Fatty fish (salmon, mackerel, sardines): sources of omega-3s with anti-inflammatory and calming properties.
  • Foods rich in tryptophan (eggs, sunflower seeds, turkey): promote serotonin production, a natural antagonist to cortisol.
  • Green tea: contains L-theanine, an amino acid with relaxing effects.

On the other hand, it’s recommended to limit caffeine, alcohol, ultra-processed foods, and refined sugars, which can stimulate cortisol production.

What role does sleep play in managing cortisol?

Sleep is a natural regulator of cortisol. This hormone follows a circadian rhythm: it peaks in the morning and gradually decreases throughout the day. Quality sleep allows the body to follow this cycle and maintain hormonal balance.

In contrast, lack of sleep or irregular sleep patterns can disrupt this rhythm, leading to excessive cortisol production—especially in the evening—further disturbing sleep and creating a vicious cycle.

To restore balance:

  • Go to bed and wake up at regular times
  • Avoid screens at least one hour before bed to promote faster sleep onset.
  • Create a sleep-friendly environment (quiet, dark, cool temperature)
  • Practice relaxation techniques before bedtime (breathing, meditation, reading)

Does exercise reduce or increase cortisol?

Physical activity can both raise and lower cortisol levels, depending on the intensity, duration, and regularity of the exercise.

Moderate and regular activity (like walking, yoga, swimming, gentle cycling) helps naturally lower cortisol by reducing stress, improving mood, and promoting better sleep.

However, intense or prolonged training (especially without sufficient recovery) can cause a temporary rise in cortisol, and even lead to imbalance if done too frequently or excessively. The key is to strike a balance between physical activity and recovery. Exercise should be a tool to release pressure, not a source of additional stress.

Which supplements or herbs can help regulate cortisol?

Certain adaptogenic herbs and natural supplements can support the body’s stress response and help regulate cortisol production:

  • Ashwagandha: an Ayurvedic herb known for its anti-stress effects and ability to lower cortisol levels.
  • Rhodiola rosea: improves stress resilience and helps maintain mental energy.
  • Maca: supports endocrine functions and can help with stress-related fatigue.
  • Magnesium: an essential mineral that helps calm the nervous system and reduce cortisol secretion.
  • L-theanine: an amino acid found in green tea, known for its relaxing properties without causing drowsiness.
  • Omega-3: polyunsaturated fatty acids with anti-inflammatory and hormone-balancing effects on stress hormones.

Before starting any supplementation, it is recommended to seek advice from a healthcare professional, especially if you are undergoing medical treatment or have a specific health condition.

WHAT IS THE LINK BETWEEN CORTISOL AND WEIGHT GAIN?

While cortisol is essential for maintaining the body's balance, it can have undesirable side effects when secreted in excess over long periods. Among these, weight gain—particularly around the abdominal area—is one of the most common. This phenomenon is closely linked to chronic stress and cortisol’s impact on metabolism.

Can excess cortisol promote weight gain?

Yes, a persistently high level of cortisol can lead to gradual weight gain, even in people who eat relatively well. This link is explained by several biological mechanisms:

  • Cortisol stimulates appetite, especially for foods rich in sugar and fat.
  • It slows down metabolism, making calorie burning less efficient.
  • It promotes fat storage, particularly in the abdominal area.
  • It affects insulin activity, leading to increased energy storage in the form of fat.

In other words, under stress, the body prepares for a perceived "threat" by preserving energy stores—resulting in weight gain.

Why does chronic stress lead to abdominal fat accumulation?

When stress becomes constant, the body is exposed to regular cortisol secretion. This hormone tends to direct fat storage to the visceral area—that is, around internal organs. Abdominal fat is particularly problematic, as it’s associated with increased risk of metabolic issues (diabetes, hypertension, chronic inflammation).

Several factors worsen this process:

  • Emotional eating (snacking under stress)
  • Reduced physical activity
  • Disrupted sleep
  • Elevated sugar and insulin levels in the bloodstream

Chronic stress therefore encourages the body to store more fat—especially in the belly, where it’s least desirable.

How to fight cortisol-induced weight gain?

To counter the effects of cortisol on weight, it’s necessary to take action on multiple fronts:

  • Stress reduction: through breathing exercises, meditation, heart coherence, or other calming practices.
  • Regular physical activity: focus on moderate exercises that promote relaxation and hormonal balance.
  • Balanced nutrition: high in fiber, protein, and omega-3s, while avoiding refined sugars and processed foods.
  • Quality sleep: crucial to restore a natural hormonal rhythm.
  • Professional support if needed: especially in cases of intense stress, anxiety, or metabolic disorders.

It’s important to understand that stress-related weight gain cannot be solved by dieting alone. It requires a comprehensive approach focused on restoring hormonal and emotional balance.

WHAT IS THE CONNECTION BETWEEN CORTISOL AND EXERCISE?

Physical exercise and cortisol have a complex relationship. In fact, cortisol is a natural response of the body to physical stress, and training—whether moderate or intense—can lead to increased secretion of this hormone. However, the impact of exercise on cortisol depends on several factors, including the type, duration, and intensity of the workout.

Does exercise increase cortisol?

Yes, exercise naturally increases cortisol levels, especially during high-intensity or prolonged workouts. This is a normal body response that helps mobilize energy to meet the physical demand. Cortisol helps to:

  • Release fatty acids and glucose, which are quick energy sources needed during exercise.
  • Regulate immune function in response to the physiological stress induced by exercise.

However, this cortisol rise is temporary and beneficial as long as it is controlled and followed by proper recovery periods. Prolonged cortisol elevation due to overtraining or insufficient rest can become harmful to health.

Should intense workouts be avoided during stressful periods?

Intense exercise can indeed intensify existing stress in the body, potentially leading to negative effects during high-stress periods. When cortisol is already elevated due to emotional or mental stress, intense physical activity can result in:

  • Excessive cortisol increase, which may disrupt hormonal regulation.
  • A higher risk of injuries, extreme fatigue, or overtraining, since the body is already under pressure.
  • Sleep disturbances, as excess cortisol can make it harder to fall asleep, impacting recovery.

In such cases, it may be better to focus on moderate activities like walking, yoga, or relaxation exercises that help reduce cortisol without adding physical strain.

What types of exercise help balance cortisol?

Certain types of exercise are particularly effective in regulating cortisol and promoting a sense of calm and relaxation:

  1. 1. Yoga and meditation: These practices encourage deep, controlled breathing, which helps reduce cortisol levels and improve stress management. They also stimulate the production of dopamine and serotonin, neurotransmitters linked to relaxation and well-being.
  2. 2. Walking and low-intensity activities: Moderate activity like brisk walking helps lower cortisol while boosting energy levels. This type of exercise is especially helpful during periods of high stress, as it allows the body to unwind gradually.
  3. 3. Moderate strength training: Resistance training with light to moderate weights can help balance stress hormones, especially when intensity and volume are moderate and recovery is adequate.
  4. 4. Moderate cardio exercises: Low to medium-intensity aerobic sessions, like swimming or cycling, are also effective in lowering cortisol without overstimulating it.

In summary, the key to managing cortisol through exercise lies in balance: moderate and regular workouts, combined with rest and recovery periods, help maintain optimal hormonal balance while preventing physical or mental exhaustion.

CORTISOL AND ANXIETY: WHAT'S THE CONNECTION?

Cortisol, often referred to as the stress hormone, is a key part of the body’s response to stress. However, its role goes beyond managing stressful situations—it is also involved in psychological disorders such as anxiety. The connection between cortisol and anxiety is complex and involves hormonal and brain interactions.

Is cortisol responsible for panic attacks?

Cortisol plays a major role in the body's stress response, but it is not directly responsible for panic attacks. However, chronically high levels of cortisol can contribute to a state of emotional hyperreactivity, increasing sensitivity to stress and the likelihood of experiencing anxiety. Anxiety, especially panic attacks, can be triggered or worsened by hormonal imbalances caused by excess cortisol, which affects the brain—particularly the limbic system (the emotional regulation center).

Panic attacks often occur in situations where the body perceives a threat, whether real or imagined. If cortisol remains elevated for prolonged periods, it can lead to a state of hypervigilance, making a person more susceptible to anxiety symptoms such as palpitations, rapid breathing, and feelings of dread.

Can regulating cortisol relieve anxiety?

Yes, regulating cortisol can be an effective way to relieve anxiety. When cortisol levels are under control, the body and mind are less reactive to stressors. Several natural strategies can help regulate cortisol levels and, in turn, reduce anxiety:

  • Relaxation and meditation: These techniques promote the production of anti-stress hormones like serotonin and oxytocin, which lessen cortisol’s impact on the body.
  • Proper sleep management: Quality sleep is crucial for regulating cortisol and restoring hormonal balance.
  • Physical activity: Moderate exercise, such as walking or yoga, can reduce cortisol production and improve mood, helping to ease anxiety symptoms.
  • Adaptogenic herbs: Plants such as ashwagandha and rhodiola are known for their ability to regulate cortisol and reduce anxiety-related symptoms.

By reducing cortisol, these approaches help soothe the nervous system and decrease the frequency and intensity of anxiety episodes.

What’s the difference between anxiety, stress, and cortisol?

Although anxiety, stress, and cortisol are closely related, they refer to different concepts:

  • Stress is a normal response to external pressures (work, personal events, etc.). It triggers cortisol production to help the body cope. However, chronic stress can lead to hormonal imbalances, including cortisol overproduction.
  • Anxiety is an emotional state marked by excessive nervousness or worry. Unlike stress, which is usually a response to an external situation, anxiety can persist even without an immediate trigger and is often linked to hormonal disruptions—especially involving cortisol.
  • Cortisol is a hormone secreted by the adrenal glands in response to stress. It helps the body deal with perceived threats by releasing energy, but excessive levels of cortisol—especially from chronic stress—can contribute to the development of anxiety.

Cortisol is therefore a key factor in stress regulation and can worsen anxiety if its levels are not balanced. Managing cortisol is thus an important lever in controlling stress and anxiety symptoms.

WHAT ARE THE MEDICAL TREATMENTS FOR CORTISOL IMBALANCE?

An imbalance in cortisol—whether too high or too low—can have serious health consequences. If you experience symptoms of a cortisol-related hormonal disorder, it is essential to consult a healthcare professional to obtain an accurate diagnosis and begin appropriate treatment. Medical treatments vary depending on the type of hormonal imbalance and its underlying cause.

When should you consult for a cortisol disorder?

It is recommended to consult a doctor if you experience persistent symptoms that may be related to high or low cortisol levels. These symptoms can include:

  • Severe fatigue that doesn’t go away even with rest
  • Unexplained weight gain, especially around the abdomen
  • Sleep disturbances (insomnia, frequent waking)
  • Loss of muscle mass
  • Mood changes, including anxiety, irritability, or depression
  • Muscle and joint pain
  • Skin darkening (in some cases of cortisol deficiency)
  • High or low blood pressure

A blood test or cortisol test, prescribed by a doctor, is necessary to confirm dysfunction. If in doubt, seeing an endocrinologist is a good option, as this specialist is trained to treat hormonal imbalances.

What is Cushing’s syndrome or Addison’s disease?

Two of the most well-known conditions related to cortisol dysfunction are Cushing’s syndrome and Addison’s disease:

  • Cushing’s syndrome: This results from excess cortisol production, often caused by a benign tumor of the pituitary gland (pituitary adenoma) or adrenal glands. It leads to symptoms such as rapid weight gain—especially in the abdomen and face (moon face), thin and fragile skin, high blood pressure, easy bruising, and sometimes bone fragility.
  • Addison’s disease: On the other hand, Addison’s disease occurs when the adrenal glands don’t produce enough cortisol. Symptoms include extreme fatigue, dizziness, weight loss, skin darkening, low blood pressure, and gastrointestinal problems.

Both conditions require immediate medical care, often involving thorough diagnostic tests such as hormone panels, imaging exams (CT scan, MRI), and stimulation tests.

Are there medications to lower cortisol?

Yes, there are several medical treatments to regulate cortisol levels, primarily used in pathological conditions such as Cushing’s syndrome or cortisol overproduction. These include:

  • Cortisol production inhibitors: Medications like metyrapone (synthetic hydrocortisone) or ketoconazole (an antifungal with anti-corticosteroid effects) can reduce cortisol production in the adrenal glands.
  • Cortisol antagonists: Drugs like mifepristone may be prescribed to block cortisol’s effects on the body, particularly in cases of Cushing’s syndrome.
  • Hormone replacement therapy (HRT): In the case of Addison’s disease, where cortisol production is insufficient, replacement therapy using hydrocortisone or prednisone is given to compensate for the deficiency.

It is important to note that these treatments should only be administered under medical supervision, as improper management of medications can lead to serious side effects.

COACH'S TIPS

  • The effects of cortisol during training are well known. Athletes often tend to overdo it, leading to overtraining. Overtraining is a state in which the body is subjected to excessive physical stress. Signs may include persistent fatigue, decreased performance, sleep disturbances, muscle soreness, and hormonal changes. High cortisol levels due to lack of recovery or excessive workload can worsen these symptoms and lead to a hormonal imbalance, affecting both physical and mental health. This is why rest is essential.

  • If you feel your strength is dropping, your motivation to train is disappearing, or you're experiencing repeated injuries—then you're likely in a phase of overtraining. Ease off!!

Yves Bondroit coach for QNT

Posted in: Our tips

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