Boost Your Energy & Immune System with Cortisol & Adrenaline
Dr. Andrew Huberman discusses the biology of cortisol and adrenaline (epinephrine), revealing their roles in energy, focus, and immune function. He provides science-supported tools to regulate these hormones, enhance learning, and optimize the immune system, emphasizing timing and deliberate practices.
Deep Dive Analysis
17 Topic Outline
Intermittent Fasting, Ghrelin, and Growth Hormone
Stomach Growling and Hot Baths for Growth Hormone
Cortisol and Epinephrine: Biology and Functions
Timing Cortisol Peak with Morning Light Exposure
Benefits of Brief Cortisol and Adrenaline Spikes
Deliberate Stressors to Increase Adrenaline and Cortisol
Leveraging Acute Stress for Immune System Enhancement
Morning Light, Cortisol, and Thyroid Hormone Timing
Adrenaline's Role in Post-Learning Memory Consolidation
Chronic Coffee Consumption and Brain Connectivity
Understanding Nootropics and Neural Energy
Biology of Comfort Foods and Chronic Stress Feedback Loops
How Stress Contributes to Hair Graying
Supplements and Compounds Affecting Cortisol Levels
Fasting for Energy, Alertness, and Immune System Function
Recognizing When Stress-Inducing Practices Become Detrimental
Separating Brain and Body Stress Responses for Control
12 Key Concepts
Ghrelin's Role in Growth Hormone Release
Ghrelin, the hunger hormone, can bind to growth hormone-releasing hormone receptors in the brain, stimulating growth hormone release, particularly during fasting. This mechanism explains how intermittent fasting can increase growth hormone levels.
Cortisol as a Steroid Hormone
Cortisol is a steroid hormone derived from cholesterol, similar to estrogen and testosterone. It competes with these sex hormones for cholesterol precursors, meaning higher stress (and thus cortisol production) can reduce the resources available for estrogen and testosterone synthesis.
Cortisol Release Pathway
Cortisol release begins in the brain with corticotropin-releasing hormone (CRH), which stimulates the pituitary to release ACTH. ACTH then acts on the adrenal glands (above the kidneys) to release cortisol, a hormone primarily associated with energy and alertness.
Epinephrine/Adrenaline Release Pathway
Epinephrine (adrenaline) is released from sympathetic chain ganglia throughout the body, causing widespread effects like increased heart rate and breathing. It's also released from the adrenal glands in pulses and from the locus coeruleus in the brain, which promotes alertness.
Dopamine's Role in Buffering Epinephrine
When an individual cognitively reframes a stressor (e.g., telling oneself they enjoy it), it liberates dopamine. Dopamine is a precursor to epinephrine, and its release can buffer the epinephrine response, allowing for greater amplitude of epinephrine release and a sense of control.
Epinephrine and Immune System Signaling
Epinephrine acts as a signal from the nervous system to immune organs like the spleen, instructing them to release killer cells (B cells and T cells) to combat infections. Brief, acute increases in epinephrine can therefore enhance short-term immune function.
Habitual Coffee Drinking and Brain Connectivity
Chronic daily coffee consumption can alter brain circuitry, leading to a shift or bias towards anxiety, even when caffeine is not ingested. This involves increased connectivity between brain areas related to anxiety.
Two Categories of Nootropics
Nootropics, or 'smart drugs,' generally fall into two categories: those that increase blood glucose (e.g., racetams, amphetamines) and those that increase cholinergic system activity (e.g., choline, fosostigmine). The episode emphasizes that the 'neural energy' from neurotransmitters like epinephrine and cortisol is distinct from glucose-derived energy.
Cortisol Feedback Loops (Negative vs. Positive)
Normally, high cortisol levels trigger a negative feedback loop, shutting down its production. However, chronic stress (lasting more than 4-7 days) can switch this to a positive feedback loop, where high cortisol levels *stimulate* further cortisol release, creating a cascade of stress.
Bombesin and Hunger Suppression
Bombesin is a peptide hormone that reduces eating. Short-term stress can liberate bombesin, leading to a temporary suppression of hunger.
Melanocytes and Stress-Induced Hair Graying
Activation of the sympathetic nervous system (stress response) can deplete melanocytes in hair stem cells. Melanocytes are responsible for hair pigmentation, so their depletion due to chronic stress can accelerate hair graying.
Glycyrrhizin in Licorice
Licorice contains glycyrrhizin, a compound that increases serum cortisol and blood pressure while decreasing testosterone and estrogen. This makes licorice potentially detrimental during periods of chronic stress or when optimizing sex hormones.
9 Questions Answered
Yes, intermittent fasting can increase growth hormone levels by causing the hunger hormone ghrelin to bind to growth hormone-releasing hormone receptors, stimulating its release.
When blood glucose is low during fasting, ghrelin is secreted, which then binds to the growth hormone-releasing hormone receptor in the brain, stimulating growth hormone release.
Stomach growling occurs when the smooth muscles lining the stomach contract and churn, even when there's no food inside, creating the audible sounds.
Hot baths can increase growth hormone, but the required temperatures carry a risk of burns, and the increases are generally less substantial than those achieved with sauna exposure.
To ensure your highest cortisol levels occur first thing in the morning, get outside and view sunlight (even on overcast days) for 2-10 minutes within 30 minutes of waking, without sunglasses.
Yes, brief, acute bouts of stress, which involve increases in epinephrine and cortisol, can enhance immune system function for about one to four days by signaling immune organs to combat infections.
Getting cortisol released early in the day by viewing morning light helps properly time thyroid hormone release, which is critical for setting your metabolic rate and overall energy levels.
Increases in epinephrine and cortisol, particularly when they occur immediately after a learning event, enhance memory consolidation and neuroplasticity, ensuring the information is retained long-term.
If you are already feeling exhausted, burnt out, or experiencing chronic stress from life events, further engaging in stress-inducing practices like prolonged fasting, excessive cold exposure, or intense exercise can drive you deeper into chronic stress, leading to negative health effects.
27 Actionable Insights
1. Early Morning Sunlight Exposure
Get outside and view sunlight within 30 minutes of waking for 2-10 minutes (2 min if very bright, 10 min if not so bright), without sunglasses and never looking directly at the sun. This stimulates appropriate early morning cortisol release, improving focus, energy, and learning throughout the day, and prevents late-shifted cortisol which is linked to depression and anxiety.
2. Maintain Consistent Daily Schedule
Maintain a consistent schedule for light exposure, feeding, exercise, and sleep. This consistency is the most powerful way to buffer against the negative mental and physical health effects of stress.
3. Deliberate Stress for Energy
Deliberately engage in practices that increase epinephrine and cortisol (e.g., cold showers, cyclic breathing, high-intensity interval training, weight lifting) to boost energy and alertness. These activities act as ‘stressors’ that increase alertness and energy, and can help buffer against unhealthy levels of stress hormones when done deliberately and intermittently.
4. Calm Mind During Physical Stress
During deliberate physical stressors (e.g., cold exposure, intense exercise), consciously try to calm your mind while maintaining physical alertness. This practice helps separate the body’s adrenaline response from the brain’s, building resilience and the ability to stay calm under pressure.
5. Comprehensive Learning & Memory Protocol
Implement a learning protocol: 90-minute focus/learning session, immediately followed by a short, deliberate stressor (cold shower, breathing, intense exercise), then a non-sleep deep rest (NSDR) session, and finally, a good night’s sleep. This sequence optimizes brain states for attention, consolidates learning through post-stress hormone spikes, and facilitates neuroplasticity during rest and sleep.
6. Post-Learning Adrenaline for Memory
Increase alertness and epinephrine/cortisol levels immediately after a learning session (e.g., through breathing exercises, cold showers, hard run, HIIT). This post-learning spike in stress hormones consolidates information and primes brain circuits for neuroplasticity, enhancing memory retention.
7. Boost Immunity with Adrenaline
Engage in short bouts (e.g., <1 hour) of intense exercise, cold water exposure, or cyclic breathing 2-3 times a week. These activities increase epinephrine, which signals immune organs to combat infections, thereby bolstering the immune system in the short term (1-4 days).
8. Fasting for Neural Energy
Utilize fasting (e.g., skipping breakfast, delaying first meal) to increase neural energy, alertness, and prime the system for immune-boosting or learning-enhancing protocols. Fasting increases epinephrine and cortisol, providing neural energy and alertness, and can enhance the effects of subsequent immune-boosting or learning-consolidation activities.
9. Ashwagandha for Cortisol Reduction
If experiencing chronic stress, consider supplementing with Ashwagandha (14.5-27.9% cortisol reduction shown in studies), taking it later in the day or evening. Ashwagandha has a significant anxiolytic effect and can reduce cortisol levels, helping to mitigate the negative impacts of chronic stress.
10. Morning & Exercise Electrolyte Intake
Dissolve one packet of Element in 16-32 ounces of water and drink it first thing in the morning, and also drink it during any physical exercise. This ensures adequate hydration and electrolytes, which are critical for optimal brain and body function and vital for cell function, especially neurons.
11. Strategic Caffeine for Plasticity
Delay caffeine intake until 2 hours after waking and consider consuming it later in learning/focus sessions, rather than before. This timing aims to enhance brain plasticity around learning sessions and avoids potential chronic anxiety effects associated with habitual early caffeine use.
12. Dissociate Brain-Body Stress
Regularly practice deliberately increasing physical adrenaline (e.g., cold exposure, intense exercise) while consciously maintaining a calm mental state. This trains the ability to dissociate the body’s stress response from the mind’s, improving mental regulation and preventing negative reactions to unwanted stressful events.
13. Prevent Chronic Stress Cascade
Actively work to prevent chronic stress (stress lasting more than 1-3 days) and learn to turn off the stress response. Chronic stress creates a positive feedback loop, amplifying stress and leading to numerous negative health effects, including metabolic dysfunction, sleep disturbances, and immune suppression.
14. Avoid Chronic Fasting in Stress
If experiencing very high levels of life stress, avoid chronic fasting. Combining high life stress with chronic fasting can lead to chronic stress, causing negative effects on reproductive hormones, hair, sleep, and immune function.
15. Self-Assess Stress & Energy
Self-assess your current stress and energy levels to determine if you need to increase (e.g., cold baths, intense breathing) or decrease/buffer (e.g., warm baths, ashwagandha) your epinephrine and cortisol. This allows for personalized regulation of hormones based on individual needs, preventing under-activation or over-activation.
16. Cyclic Breathing for Alertness
Perform cyclic breathing: 25-30 deep inhale-exhale cycles, followed by a 15-30 second exhale hold, repeated 2-3 times. Always do this on dry land and never near water, and consult your doctor. This releases adrenaline and norepinephrine, increasing energy and alertness.
17. Adjust Morning Light Duration
Adjust morning light exposure duration based on conditions: 5-10 minutes on bright, clear days; 10-20 minutes on light cloud days; 30 minutes on dense overcast days. Avoid relying on indoor artificial light, which requires about six hours to achieve the same effect. This ensures sufficient lux exposure to properly time cortisol release, which is vital for energy and focus.
18. Keep Stress Spikes Brief
When experiencing brief stress (e.g., from traffic, frustrating emails), aim to keep the cortisol and epinephrine spikes brief. This prevents chronic elevation of stress hormones, which can have negative health impacts.
19. Avoid Comfort Foods in Stress
Be mindful of cravings for sugary and fatty ‘comfort foods’ during periods of chronic stress and try to avoid them. Chronic stress can trigger a biological drive to consume these foods, which can lead to metabolic issues and further amplify the stress response.
20. Offset Stress-Induced Hair Graying
To offset stress-induced hair graying, consistently practice stress regulation (e.g., NSDR, meditation, massages, vacations) and ensure ample sunlight exposure. Chronic stress depletes melanocyte stem cells in hair follicles, leading to graying; stress regulation and sunlight can counteract this.
21. Apigenin for Evening Calm
Consider taking 50mg of Apigenin (found in chamomile) before bedtime. It has an anxiolytic effect, calming the nervous system, and a mild effect in reducing cortisol, which can help with evening stress.
22. Avoid Licorice During Stress
Avoid consuming licorice, especially during periods of chronic stress or if trying to optimize testosterone and estrogen levels. Licorice contains glycyrrhizin, which increases cortisol, blood pressure, and can decrease testosterone and estrogen.
23. Fasting Boosts Growth Hormone
Practice intermittent fasting. This increases growth hormone levels by allowing ghrelin (hunger hormone) to bind to growth hormone-releasing hormone receptors, doubling growth hormone in the waking state, which can burn body fat and improve tissue health.
24. Caffeine for Acute Immune Boost
Consider consuming caffeinated tea or coffee (while staying hydrated) for an acute immune system boost. Caffeine can increase epinephrine, which bolsters the immune system, similar to other short-term stressors.
25. Cautious Hot Bath for GH
Take hot baths if tolerable and safe. This can lead to some growth hormone release, though less than sauna exposure, but caution is advised due to the risk of burns from high temperatures needed.
26. Consult Doctor for Temperature
Consult a doctor before engaging in hyperthermia or hypothermia practices (e.g., cold/ice baths, hot showers/baths beyond comfortable norms). This ensures safety when experimenting with extreme temperature exposures.
27. Improve Digestion by Chewing
Chew your food better. This prevents stomach growling, which occurs when stomach muscles churn without food present.
5 Key Quotes
The fact of the matter is that epinephrine is your best friend when it comes to your immunity, when it comes to protecting you from infection.
Andrew Huberman
The body doesn't distinguish between a troubling text message, ice, tumor breathing, or high-intensity interval training or any other kind of exercise. It's all stress.
Andrew Huberman
Cognitively reframing that and telling yourself, I like this, I enjoy it, is not going to change the way that that molecule impacts your body and brain.
Andrew Huberman
Habitual coffee drinkers display a distinct pattern of brain functional connectivity.
Andrew Huberman
There's great power as we learned today in having your body activated by some sort of stimulus... but learning to stay calm in your mind.
Andrew Huberman
3 Protocols
Morning Light Exposure for Cortisol Timing
Andrew Huberman- Wake up and within 30 minutes, go outside.
- View sunlight for 2-10 minutes (2 minutes if very bright, 10 minutes if not so bright or cloudy).
- Do not wear sunglasses and never look directly at the sun to avoid eye damage.
Cyclic Inhale-Exhale Breathing (Wim Hof/Tummo Style)
Andrew Huberman- Take 25-30 deep, repeated inhales and exhales.
- After the last exhale, hold your breath for 15-30 seconds.
- Repeat this cycle two more times (total of three cycles).
- (Optional) After the third exhale hold, take a big inhale and hold it for a few seconds.
- Always perform this on dry land, never while driving, operating heavy machinery, or near water.
Optimal Learning and Memory Enhancement Protocol
Andrew Huberman- Engage in a 90-minute session of focused learning or concentration.
- Immediately after the session, perform an activity that increases adrenaline (e.g., cold shower, Wim Hof/Tummo type breathing, ice bath, hard run, or high-intensity interval training).
- Follow this with a non-sleep deep rest (NSDR) session.
- Ensure a good night's sleep.
- (Optional) Consume caffeine towards the tail end of the learning episode to enhance plasticity.