Primary Causes & Action Plans

Cortisol (Morning)

Should be high in morning to energize you; low cortisol causes fatigue
Morning cortisol (tested at 8 AM) should be high to promote wakefulness and energy. Low morning cortisol is a hallmark of HPA axis exhaustion, producing fatigue, difficulty waking, and low blood pressure. This is distinct from pathological hypocortisolism (like Addison's disease).
Target 10-20 mcg/dL (8 AM)
Suggested Action Plan

Sleep 8+ hours nightly (crucial for cortisol recovery). Reduce exercise intensity temporarily (vigorous exercise worsens HPA fatigue). Increase caloric and micronutrient intake. Manage stress through meditation, yoga, or breathwork. Retest in 3 months.

DHEA-S (DHEA-Sulfate)

Drops with chronic stress; supports stress resilience and immune function
DHEA-S is the precursor to testosterone and estrogen and is suppressed by chronic stress. Low DHEA-S reflects prolonged HPA axis activation and correlates with fatigue, poor immune function, and poor stress resilience. Restoring DHEA-S improves recovery.
Target 150-350 mcg/dL (women); 350-430 mcg/dL (men)
Suggested Action Plan

Support DHEA recovery through stress management, sleep, and adaptogenic herbs (ashwagandha, rhodiola, cordyceps). DHEA supplementation is available but should be monitored by a physician. Retest in 3-6 months.

Fasting Glucose

Cortisol regulates glucose; low cortisol impairs blood sugar control and energy
Cortisol is essential for maintaining fasting glucose between meals. When cortisol is low, blood glucose can drop excessively, producing hypoglycemic symptoms (tremors, brain fog, anxiety) and further HPA axis stress.
Target < 90 mg/dL (optimal)
Suggested Action Plan

Stabilize blood sugar through frequent small meals (with protein and healthy fat), avoiding skipped meals and long fasts. Eat simple carbs with breakfast to support morning cortisol rise. Avoid excessive cardio, which further depletes cortisol.

Magnesium

Deficiency prevents stress recovery; repletion is essential for HPA axis healing
Magnesium is depleted by chronic stress and is required for nervous system relaxation and cortisol regulation. Deficiency perpetuates HPA axis dysregulation. Magnesium repletion is essential for recovery.
Target > 2.0 mEq/L (serum)
Suggested Action Plan

Supplement with magnesium glycinate 400-500 mg daily. Magnesium citrate can help with any constipation. Add magnesium-rich foods (leafy greens, pumpkin seeds, dark chocolate). Magnesium is the single most important nutrient for HPA axis recovery.

Thyroid Panel (TSH)

Thyroid function often declines with HPA axis exhaustion
The HPA axis and thyroid axis are tightly linked. Chronic stress suppresses thyroid function; hypothyroidism worsens stress response. Testing thyroid is essential in HPA axis dysfunction.
Target TSH: 1.0-2.5 mIU/L; Free T4: 1.0-1.5 ng/dL
Suggested Action Plan

If thyroid function is low, thyroid hormone replacement helps HPA axis recovery. Work with a thyroid-knowledgeable doctor. Retest in 6-8 weeks after treatment adjustment.

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Getting Started

1
Test Your HPA Axis Status

Order a 4-point salivary cortisol test (morning, noon, evening, bedtime) plus DHEA-S. This reveals your specific cortisol pattern and guides recovery strategies. Normal blood cortisol misses HPA dysfunction; salivary testing is superior.

2
Prioritize Sleep Above All Else

Sleep is when your HPA axis recovers. Aim for 8-9 hours nightly. No amount of supplements or stress management techniques can overcome chronic sleep deprivation. Make sleep your top priority.

3
Reduce Exercise Intensity Temporarily

Vigorous exercise further stresses an exhausted HPA axis. Switch to gentle activities: walking, stretching, yoga, swimming. Once recovered (in 3-6 months), gradually reintroduce higher-intensity exercise.

4
Supplement Strategically

Magnesium (400-500 mg glycinate daily) is the most important supplement. Add adaptogenic herbs: ashwagandha, rhodiola, or cordyceps. These support stress adaptation without overstimulating an exhausted system.

5
Retest in 3-6 Months

With comprehensive HPA axis support, cortisol and DHEA typically normalize within 3-6 months. Retest to confirm recovery and adjust interventions if needed.

Why I built this guide.

"HPA axis recovery is possible with the right support. Testing is the first step to understanding your stress capacity."

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