Stress axis · Morning peak

Cortisol AM(Cort AM)

Cortisol peaks 30–45 minutes after waking — the cortisol awakening response (CAR). A flat or inverted curve signals adrenal dysregulation or chronic stress.

Women in the follicular phase have slightly higher basal cortisol than men in meta-analysis (Hedges' g ~0.13), and cortisol reactivity is blunted in the luteal phase vs follicular. Oral contraceptives raise total cortisol via CBG elevation but leave free cortisol unchanged. Pregnancy raises both total and free cortisol substantially.

Optimal range (women)

reproductive · perimenopause · postmenopause · pregnancy

6–18µg/dL

Cycle: Follicular > luteal for basal cortisol; OCPs raise total cortisol. Late-night salivary cortisol is preferred for Cushing screening — measure on cycle day 1-10 if possible.

Clinical "normal"

5–23 µg/dL

Avg. cost (US)

$55

Test frequency

Annually; quarterly if optimizing for stress

When to measure

08:00 AM serum draw (within 1 hour of waking). For Cushing screening prefer late-night salivary cortisol or 24h urinary free cortisol. Cycling women: follicular phase preferred.

How to measure

Serum cortisol. For chronic stress assessment, salivary or urine cortisol curves are more informative than a single morning serum value.

Average cost

≈ $55 cash price. Often covered by insurance with relevant ICD-10.

Signs your level is off

Symptoms if low

Fatigue, postural hypotension, hyperpigmentation, salt craving, nausea, weight loss, hypoglycemia (think primary adrenal insufficiency). In women specifically: persistent amenorrhea with low estradiol may reflect hypothalamic suppression from chronic undernutrition / overtraining (RED-S / functional hypothalamic amenorrhea).

Symptoms if high

Central weight gain, moon facies, purple striae, easy bruising, proximal muscle weakness, hypertension, menstrual irregularity, hirsutism — workup Cushing's with 24h urinary free cortisol, late-night salivary cortisol, and low-dose dexamethasone suppression.

If your level is low

Phosphatidylserine: drowsiness

Supplement

Adaptogens (ashwagandha)· 300-600 mg KSM-66 or Sensoril ashwagandha extract daily

Form: capsule

Modulates HPA axis; modest cortisol reduction in stressed adults

Foods

regular meals (avoid skipping)
adequate sodium if hypoadrenal
reduce caffeine if AM cortisol blunted

Lifestyle

address chronic undernutrition or overtraining
sleep 7-9h
mind-body practices (yoga, breathwork)
increase calorie intake if functional hypothalamic amenorrhea

Medication (if prescribed)

Hydrocortisone (if Addison's confirmed)· 15-25 mg/day in divided doses

Form: Oral, physician-directed

Reference only. Speak with a licensed clinician before any prescription intervention.

Caution: Low AM cortisol with hyperkalemia or hyperpigmentation requires urgent endocrine workup (ACTH stim test). Do not self-treat with hydrocortisone.

If your level is high

Ashwagandha: thyroid interaction

Supplement

Phosphatidylserine· 300-600 mg/day

Form: capsule

Blunts ACTH and cortisol response to stress in some studies

Foods

Mediterranean pattern
reduce alcohol
limit caffeine after noon

Lifestyle

CBT or mindfulness-based stress reduction
aerobic exercise (zone 2)
sleep hygiene
screen and treat OSA
reduce alcohol

Medication (if prescribed)

Address underlying cause (depression, OSA, Cushing screening)· N/A

Form: N/A

Reference only. Speak with a licensed clinician before any prescription intervention.

Caution: Sustained elevation with central obesity/striae/HTN: screen for Cushing's with 24h UFC + late-night salivary cortisol + 1 mg overnight dex suppression. OCPs elevate total cortisol — interpret with assay-specific reference intervals.