How to Control Your Cortisol & Overcome Burnout

Huberman emphasizes that cortisol's role is often misunderstood because people tend to associate it solely with negative stress responses. Instead, cortisol should be viewed as a hormone that supports brain energy and overall bodily function. Its effects depend heavily on the timing and levels of release, which follow a natural 24-hour circadian rhythm. Proper regulation of this rhythm is fundamental to maintaining health, mood, sleep quality, and immune function.

The Circadian Rhythm of Cortisol

A central theme of the podcast is the 24-hour circadian rhythm of cortisol secretion. Huberman explains that cortisol levels are naturally high shortly after waking and low during the hours before and early in sleep. This rhythm is crucial because it aligns energy availability with the demands of the day and allows the body to rest and recover at night.

The cortisol cycle is divided into four phases: a minimal secretion phase before and shortly after sleep onset, a preliminary rise during the middle of sleep, a rapid increase in the final hours of sleep coinciding with REM sleep, and a peak after waking known as the cortisol awakening response. This peak is vital for alertness and energy in the morning. Understanding and supporting this rhythm through lifestyle choices can prevent burnout and improve overall well-being.

The HPA Axis and Cortisol Regulation

Huberman delves into the biological mechanisms controlling cortisol production, focusing on the hypothalamic-pituitary-adrenal (HPA) axis. The process begins in the hypothalamus, where neurons in the paraventricular nucleus release corticotropin-releasing hormone (CRH). This hormone signals the pituitary gland to release adrenocorticotropic hormone (ACTH), which then stimulates the adrenal glands to produce and release cortisol.

A key feature of this system is a negative feedback loop: as cortisol levels rise, they signal the hypothalamus and pituitary to reduce CRH and ACTH release, preventing excessive cortisol production. This self-regulation maintains cortisol within an optimal range, ensuring energy is available when needed but not chronically elevated, which can be harmful.

The Role of the Suprachiasmatic Nucleus (SCN) and Light

The suprachiasmatic nucleus (SCN), the brain's master circadian clock, orchestrates the timing of cortisol release by regulating the HPA axis. The SCN receives direct input from specialized retinal ganglion cells sensitive to light, particularly the transition from darkness to bright light upon waking. This input allows the SCN to synchronize cortisol release with environmental light cues.

Huberman highlights the importance of morning light exposure in amplifying the cortisol awakening response. Bright light, ideally natural sunlight, within the first hour of waking can increase cortisol levels by up to 50%, enhancing alertness, mood, and focus. This light-driven mechanism also helps ensure cortisol levels decline appropriately later in the day, supporting healthy sleep patterns.

Morning Protocols to Boost Cortisol

To optimize morning cortisol and energy, Huberman recommends several practical strategies. First, immediate exposure to bright light upon waking is essential, preferably sunlight but alternatively a 10,000 lux artificial light if natural light is unavailable. This exposure activates the SCN and boosts cortisol production.

Hydration is another underrated but powerful tool. Drinking water with electrolytes soon after waking supports adrenal function and modestly increases cortisol, improving alertness. Caffeine can also influence cortisol, but its effects depend on habitual use. For regular caffeine consumers, morning intake prolongs cortisol's presence rather than significantly increasing its peak, while non-habitual users experience a more pronounced cortisol spike. Timing caffeine intake 60 to 90 minutes after waking can help smooth cortisol's decline through the day, reducing afternoon energy crashes.

Exercise, Cold Exposure, and Cortisol

Exercise influences cortisol levels in complex ways, depending on the type, intensity, and novelty of the activity. Regular exercisers experience smaller cortisol spikes compared to those new to a workout or exercise type. Exercise acts as an entrainment cue, reinforcing the circadian rhythm of cortisol when performed consistently at the same time of day, ideally in the morning.

Deliberate cold exposure, such as cold showers or ice plunges, rapidly increases catecholamines like adrenaline and dopamine, which boost alertness and mood. While cold exposure can elevate cortisol initially, habitual exposure diminishes this effect, making it a useful but occasional tool for cortisol modulation. Huberman suggests limiting cold exposure to one or two times per week to maintain its cortisol-boosting benefits.

Evening and Nighttime Cortisol Management

As cortisol naturally declines in the afternoon and evening, maintaining low levels is critical for relaxation and sleep onset. Huberman stresses the importance of controlling light exposure in the evening to prevent unwanted cortisol spikes. Dim, warm-colored lighting, such as red or amber bulbs, minimizes stimulation of the SCN and helps keep cortisol low.

Avoiding short-wavelength blue light from screens is crucial, as it can increase cortisol and suppress melatonin, the sleep hormone. Tools like blue-light blocking glasses or phone settings that shift screen color to red can mitigate these effects. Additionally, caffeine intake should be limited to early afternoon to prevent prolonged cortisol elevation that disrupts sleep.

Nutritional Influences on Cortisol

Nutrition plays a significant role in cortisol regulation, particularly carbohydrate intake. Eating starchy carbohydrates in the evening can help lower cortisol by elevating blood glucose, which signals the hypothalamus to reduce cortisol release. This explains why carbohydrate-rich "comfort foods" often promote relaxation.

Huberman also discusses two specific foods with notable effects on cortisol metabolism: grapefruit and black licorice. Grapefruit contains compounds that inhibit enzymes responsible for cortisol breakdown, extending cortisol's active duration by 25-50%. Black licorice, through its active compound glycyrrhizin, inhibits the conversion of cortisol to inactive cortisone, significantly increasing circulating cortisol. However, licorice should be used cautiously, especially by individuals with high blood pressure or pregnant women.

Behavioral Tools for Stress Reduction

To manage acute stress and prevent cortisol spikes, Huberman advocates for breathing techniques, particularly exhale-emphasized breathing and the physiological sigh. These methods engage the parasympathetic nervous system, slowing heart rate and reducing sympathetic activation rapidly.

The physiological sigh involves a deep inhale through the nose, a second sharp inhale to fully inflate the lungs, followed by a long exhale through the mouth. Practicing this for 30 seconds to a minute can quickly calm the nervous system, making it an effective tool for real-time stress management, especially in the evening when cortisol should be low.

Supplements for Cortisol Modulation

While behavioral strategies are primary, certain supplements can support cortisol regulation. Ashwagandha is highlighted for its ability to reduce cortisol by 11-29% when taken in doses of 300-600 mg, ideally in the late afternoon or evening to avoid blunting the morning cortisol peak. Apigenin, found in chamomile, also modestly lowers cortisol and is commonly used as part of sleep-support stacks.

Magnesium threonate is mentioned for its indirect effects on cortisol suppression and sleep enhancement. Huberman cautions that supplementation should complement, not replace, foundational lifestyle practices such as light exposure, hydration, and stress management.

Patterns and Types of Burnout

Burnout manifests in two primary patterns related to cortisol dysregulation. The first pattern involves waking up with high stress and anxiety, often too early, followed by exhaustion and brain fog in the afternoon. This "wired and tired" state reflects an overly steep morning cortisol rise and insufficient regulation.

The second pattern is characterized by sluggish mornings with low energy and brain fog, but difficulty calming down and falling asleep at night. This "tired but wired" pattern indicates elevated cortisol in the evening, disrupting sleep and impairing the next day's cortisol rhythm. Recognizing which pattern one experiences is crucial for targeted intervention.

Strategies to Overcome Burnout

For those experiencing early morning stress and burnout, Huberman recommends non-sleep deep rest or yoga nidra practices immediately upon waking. These techniques promote parasympathetic activation, reduce cortisol, and can help individuals fall back asleep if needed. Hydration and morning light exposure should follow to properly time the cortisol peak.

For the second burnout pattern, the focus is on evening routines that lower cortisol: avoiding bright and blue light, limiting caffeine, engaging in relaxation breathing, and consuming starchy carbohydrates at dinner. These strategies help restore the natural cortisol trough at night, improving sleep quality and morning energy.

Huberman stresses that correcting cortisol rhythms is foundational to overcoming burnout, improving mood, cognition, and overall health.

The Broader Impact of Cortisol on Health and Longevity

Finally, Huberman connects cortisol regulation to broader health outcomes, including immune function, metabolism, and longevity. Studies show that a pronounced morning cortisol peak followed by a steep decline into the evening correlates with better disease outcomes and longer lifespan, particularly in cancer patients.

He also notes that aging and menopause are associated with a flattening of the cortisol rhythm, which may contribute to increased health risks. Maintaining a robust cortisol rhythm through lifestyle and behavioral interventions can therefore support resilience, cognitive function, and quality of life across the lifespan.