Cortisol and Chronic Stress: What Your Adrenals Are Trying to Tell You

You're wired but tired. You can't fall asleep at night, but you're exhausted when you wake up. You rely on coffee to function, and stress feels like your permanent state of being. Sound familiar?

Chronic stress doesn't just feel terrible - it shows up in your labs. And it can wreak havoc on everything from your sleep to your weight to your other hormones.

What Is Cortisol?

Cortisol is your primary stress hormone, produced by your adrenal glands. It's often called the "fight or flight" hormone because it helps you respond to danger. In acute situations, cortisol:

• Raises blood sugar for quick energy
• Increases alertness and focus
• Suppresses non-essential functions (digestion, immune response)
• Mobilizes energy stores

This response is helpful when you're running from a tiger. It's not so helpful when it's triggered constantly by work deadlines, financial stress, sleep deprivation, and doom-scrolling.

The Cortisol Rhythm

Healthy cortisol follows a diurnal rhythm:

• Highest in the morning: Cortisol should peak about 30 minutes after waking, giving you energy to start your day
• Gradually declining: Levels drop throughout the day
• Lowest at night: Cortisol should be at its lowest around bedtime, allowing melatonin to rise and sleep to come

Chronic stress disrupts this pattern, leading to various dysfunction patterns.

What "Adrenal Fatigue" Really Means

You've probably heard the term "adrenal fatigue" - the idea that your adrenals become "exhausted" from chronic stress. This isn't an official medical diagnosis, and your adrenals don't actually get tired. However, HPA axis dysfunction (hypothalamic-pituitary-adrenal axis) is very real.

With chronic stress, the communication between your brain and adrenals can become dysregulated, leading to:

High Cortisol Patterns

• Anxiety and feeling "wired"
• Insomnia - especially difficulty falling asleep
• Weight gain, especially around the midsection
• High blood sugar and insulin resistance
• Suppressed immune function
• Impaired thyroid function

Low Cortisol Patterns

• Profound fatigue, especially in the morning
• Difficulty handling stress
• Low blood pressure and dizziness when standing
• Salt cravings
• Increased infections
• Brain fog

Flipped Cortisol Patterns

• Low cortisol in the morning (hard to wake up, need coffee)
• High cortisol at night (second wind in the evening, can't sleep)
• This reverse pattern is common with chronic stress and poor sleep habits

How Cortisol Affects Your Other Hormones

Cortisol doesn't exist in isolation. It interacts with virtually every hormone system:

• Thyroid: High cortisol inhibits TSH and conversion of T4 to T3, leading to hypothyroid symptoms
• Sex hormones: Cortisol is made from the same precursor as progesterone. When stressed, your body prioritizes cortisol, leading to low progesterone
• Insulin: Cortisol raises blood sugar and promotes insulin resistance
• Melatonin: High nighttime cortisol suppresses melatonin, disrupting sleep

Testing Cortisol

Serum Cortisol

A single morning blood draw measures cortisol at one point in time. Useful for screening but doesn't capture the full picture.

DHEA-S

DHEA-S is another adrenal hormone that often declines with chronic stress. The cortisol-to-DHEA-S ratio can be more informative than either alone. A high ratio suggests chronic stress is depleting DHEA-S.

4-Point Saliva Cortisol

Measures cortisol at 4 times throughout the day to capture the diurnal pattern. This is the gold standard for assessing cortisol rhythm but requires a specialized test.

Signs Your Stress Response Needs Attention

• You need caffeine to function in the morning
• You get a "second wind" at night and can't sleep
• You feel overwhelmed by small stressors
• You're gaining weight around your middle despite diet and exercise
• You get sick frequently
• You crave salt or sugar
• You feel foggy and forgetful
• Your blood sugar or blood pressure is creeping up

Supporting Healthy Cortisol

• Prioritize sleep: 7-9 hours, with consistent sleep and wake times
• Morning light exposure: Helps set healthy cortisol rhythm
• Reduce evening light: Especially blue light, which suppresses melatonin
• Manage blood sugar: Balanced meals prevent cortisol spikes
• Exercise appropriately: Moderate exercise helps; excessive exercise can raise cortisol
• Stress management: Meditation, breathing exercises, time in nature
• Limit caffeine: Especially after noon, as it elevates cortisol

The Bottom Line

Chronic stress is not just a feeling - it has measurable effects on your body. Testing cortisol and DHEA-S can help you understand what's happening at a biochemical level and guide targeted interventions.

Your body is trying to tell you something. Testing gives you the data to listen.

Ready to understand your stress response? Get your Cortisol and DHEA-S tested with EllaDx's comprehensive hormone panel.