Dr. Andrew Huberman: How Cortisol Rhythm Prevents Burnout

The ideal pattern is a sharp rise in cortisol in the last hours of sleep and first hour after waking (cortisol awakening response), followed by a gradual decline through the afternoon and very low levels in the 4 hours before sleep and first 2 hours after lights out. This pattern supports alertness, mood, immune function, metabolic health, and robust REM and deep sleep. Any protocol you use should be evaluated by whether it reinforces this curve.

Viewing bright outdoor light (ideally sunlight) within 30–60 minutes of waking can increase cortisol by up to ~50% and anchors your circadian clock via retinal signals to the SCN. This not only boosts morning energy and mood but promotes lower cortisol in the evening through negative feedback. On cloudy days you still should get outside; when sunlight isn’t available, use a ~10,000-lux light box early in the day.

Hydrating immediately after waking modestly increases epinephrine and cortisol, improving alertness. Regular exercise in a consistent morning window anchors the cortisol peak and creates anticipatory energy; novel or late-day intense workouts can cause large cortisol spikes. For habitual caffeine users, delaying caffeine 60–90 minutes after waking flattens the mid-morning crash by extending cortisol’s effect. Occasional (not daily) cold exposure can acutely raise cortisol; frequent cold mainly boosts catecholamines without chronically elevating cortisol. Grapefruit and black licorice slow cortisol breakdown, significantly extending or raising circulating cortisol and should be used cautiously and only earlier in the day if used deliberately.

Past sundown, the system becomes extremely sensitive to light: modest indoor or screen light, especially blue/white LED, can cause large cortisol spikes and melatonin suppression. Dim indoor lights, favor floor or table lamps over overheads, shift bulbs to red/amber where possible, and use software or glasses that filter short-wavelength light. Long-exhale breathing and physiological sighs quickly reduce sympathetic activity and cortisol. Including starchy carbohydrates in the evening meal raises blood glucose, which signals less need for cortisol deployment and promotes relaxation and sleepiness.

Type 1: high, anxious morning cortisol with afternoon crash; the aim is to soften the early spike (e.g., NSDR on waking, delaying caffeine, still using light and hydration to shift the peak later) and reduce afternoon overdrop. Type 2: low, sluggish mornings with high, ruminative nighttime arousal; the focus is aggressive evening cortisol reduction (light control, breathing, carbs, possibly ashwagandha/apigenin), so that a robust morning spike can return. Identify your dominant pattern, then prioritize protocols in the problematic phase (early vs. late) before fine-tuning elsewhere.