Complete Testing & Optimization Guide
Optimal ranges, provider comparison, and strategies to improve your Cortisol levels
Included in 8 of 10 major testing providers
Stress &Adrenal Function
anxiety
Abnormal Cortisol levels can indicate underlying health issues that may go undetected without proper testing. Regular monitoring helps catch problems early when they're most treatable.
Understanding your Cortisol levels enables targeted interventions, tracks treatment effectiveness, and helps optimize your overall health and performance.
Cortisol is the primary stress hormone produced by your adrenal glands in response to physical or psychological stress, low blood sugar, inflammation, or circadian rhythm. It's often called the "fight-or-flight"hormone, but this oversimplifies its role. Cortisol is essential for survival:it regulates metabolism, blood pressure, immune function, and helps your body respond to stress. Problems arise when cortisol is chronically elevated (from chronic stress, Cushing's syndrome) or deficient (adrenal insufficiency).
Here's the critical insight:cortisol follows a strong circadian rhythm. It's highest in the morning (peak around 8 AM) to help you wake up and get moving, then gradually declines throughout the day, reaching its lowest point around midnight to allow sleep. Disruption of this rhythm—high cortisol at night, low cortisol in the morning, or chronically elevated levels—is associated with insomnia, weight gain, insulin resistance, immune dysfunction, and accelerated aging.
A single cortisol measurement isn't very informative without context of timing. Morning cortisol should be tested between 7-9 AM. A 4-point salivary cortisol test (morning, noon, evening, bedtime) better captures the daily rhythm and is useful for assessing chronic stress, adrenal dysfunction, or HPA axis dysregulation. Serum cortisol is standard for diagnosing Cushing's or Addison's disease, while salivary cortisol is better for functional assessment.
Bottom line: TSH and Free T4 alone miss people with conversion problems. Free T3 is the only way to know if you have enough active thyroid hormone at the tissue level.
| Range Type | Level | Clinical Significance |
|---|---|---|
| Optimal (Morning 7-9 AM) | 10-20 mcg/dL | Healthy morning cortisol. Peak should occur within 30 min of waking (cortisol awakening response). |
| Optimal (Evening/Bedtime) | <5 mcg/dL | Cortisol should be low at night to allow restful sleep and overnight recovery. |
| Suboptimal (Morning) | 5-10 mcg/dL | Low morning cortisol suggests blunted cortisol awakening response, adrenal dysfunction, or chronic stress/burnout. |
| High (Morning) | >25 mcg/dL | Elevated morning cortisol. May indicate acute stress, Cushing's syndrome, or HPA axis dysregulation. Retest with dexamethasone suppression test if persistently high. |
Standard lab range:anxiety
High (Bedtime/Night)
Cortisol should be low at night. Elevated nighttime cortisol impairs sleep, recovery, and drives metabolic dysfunction.
Meditation and mindfulness:10-20 min daily meditation reduces cortisol by 20-30% in studies. Apps:Headspace, Calm, Insight Timer.
Deep breathing:4-7-8 breathing (inhale 4 sec, hold 7 sec, exhale 8 sec) activates parasympathetic nervous system, lowering cortisol.
Sleep optimization:7-9 hours nightly. Sleep deprivation raises cortisol. Prioritize consistent sleep/wake times, dark room, cool temp.
Exercise (but not too much):Moderate exercise lowers cortisol. Overtraining (>90 min high-intensity daily) raises cortisol chronically.
Social connection:Loneliness and social isolation chronically elevate cortisol. Prioritize relationships, community.
Ashwagandha:300-600 mg/day reduces cortisol by 25-30% in stressed individuals. KSM-66 and Sensoril are well-studied extracts.
Rhodiola rosea:200-600 mg/day may reduce stress-induced cortisol spikes and improve mental performance under stress.
Phosphatidylserine:300-800 mg/day may blunt exercise-induced cortisol elevation.
Holy basil (tulsi):300-600 mg/day may reduce cortisol and stress markers.
L-theanine:200-400 mg/day (from green tea or supplement) promotes relaxation without sedation, may modulate cortisol response.
Note: Vitamin C:1-2 g/day. Adrenal glands have highest vitamin C concentration in body. Vitamin C supplementation blunts cortisol response to stress. | Magnesium:400 mg/day. Deficiency exacerbates stress response and cortisol elevation. | Omega-3 fatty acids:2-3 g/day EPA+DHA reduces inflammation and may lower cortisol. | Avoid excessive caffeine:>400 mg caffeine (4 cups coffee) can elevate cortisol, especially if consumed late in day.
Note: Primary adrenal insufficiency (Addison's disease):Autoimmune destruction of adrenal cortex. Requires lifelong hydrocortisone replacement (15-25 mg/day in divided doses) + fludrocortisone for aldosterone replacement. | Secondary adrenal insufficiency (pituitary failure):Requires hydrocortisone but not fludrocortisone. | Adrenal crisis prevention:Patients on steroid replacement must increase dose 2-3x during illness, surgery, or major stress to prevent life-threatening adrenal crisis.
Weight gain, especially abdominal/visceral fat|Moon face, buffalo hump (fat redistribution)|Muscle weakness, muscle wasting (especially proximal muscles)|Thin skin, easy bruising, purple striae (stretch marks)|Insomnia, difficulty falling or staying asleep|High blood pressure|High blood sugar, insulin resistance, type 2 diabetes|Osteoporosis, fractures|Mood changes:anxiety, irritability, depression|Poor wound healing, frequent infections|Irregular menstrual periods (women)|Erectile dysfunction (men)
Source:Chronic elevation of cortisol drives metabolic syndrome, visceral obesity, insulin resistance, bone loss, and immune suppression.
Cushing's syndrome:Excess cortisol from pituitary adenoma (Cushing's disease), adrenal tumor, ectopic ACTH production (small cell lung cancer), or exogenous steroids.|Chronic stress:Psychological stress, overtraining, sleep deprivation chronically activate HPA axis.|Severe depression:Major depressive disorder often associated with HPA axis dysregulation and elevated cortisol.|Alcoholism:Chronic alcohol use disrupts HPA axis, raising cortisol.|Obesity:Visceral fat produces cortisol locally and amplifies systemic cortisol response.|Obstructive sleep apnea:Intermittent hypoxia and sleep fragmentation raise cortisol.|Medications:Estrogen (oral contraceptives, HRT) increases cortisol-binding globulin, raising total cortisol.
Source:Morning cortisol (7-9 AM):Baseline to assess adrenal function and circadian rhythm. Optimal 10-20 mcg/dL.|If very low (<5 mcg/dL):Perform ACTH stimulation test to confirm adrenal insufficiency.|If very high (>25 mcg/dL):Retest and consider dexamethasone suppression test, 24-hour urinary free cortisol, late-night salivary cortisol to evaluate for Cushing's.|4-point salivary cortisol:Morning, noon, evening, bedtime. Best for assessing circadian rhythm and chronic stress. Look for blunted morning rise or elevated nighttime levels.|If treating adrenal insufficiency:Monitor for adequate replacement and stress-dose adjustments. Retest during illness.|If optimizing stress management:Retest 3-6 months after implementing lifestyle changes (meditation, sleep, adaptogens) to assess improvement in cortisol rhythm.
Cortisol follows strong circadian rhythm:peaks 30-45 min after waking (cortisol awakening response, CAR), then declines throughout the day, reaching nadir at midnight. Disruption of this rhythm (low morning cortisol, high evening cortisol, or flattened rhythm) is associated with metabolic syndrome, depression, insomnia, and increased mortality.
Source:Adam EK, et al. Diurnal cortisol slopes and mental and physical health outcomes. Psychoneuroendocrinology. 2017;83:25-41.
Chronic psychological stress causes sustained HPA axis activation and elevated cortisol. This drives visceral fat accumulation, insulin resistance, hypertension, immune suppression, bone loss, and accelerated aging. Mindfulness meditation reduces cortisol by 20-30% and improves HPA axis regulation.
Source:Epel ES, et al. Accelerated telomere shortening in response to life stress. PNAS. 2004;101(49):17312-17315.
Cushing's syndrome (chronic cortisol excess) is diagnosed with:(1) 24-hour urinary free cortisol >3x upper limit, (2) late-night salivary cortisol >0.09 mcg/dL, (3) failure to suppress cortisol after dexamethasone. Most common cause is iatrogenic (exogenous steroids), followed by pituitary adenoma (Cushing's disease).
Source:Nieman LK, et al. The diagnosis of Cushing's syndrome:an Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab. 2008;93(5):1526-1540.
| Provider | Includes Test | Annual Cost | Total Biomarkers |
|---|---|---|---|
 Superpower | ✓ | $199 | 100+ |
 WHOOP Advanced Labs | — | $349 | 65 |
 Labcorp OnDemand | — | $398 | 30+ |
| ✓ | $486 | 40+ | |
| ✓ | $468 | 83 | |
| ✓ | $798 | 100+ | |
 InsideTracker | ✓ | $680 | 48 |
 Function Health | ✓ | $499 | 100+ |
| ✓ | $900 | 70+ | |
| ✓ | $1150 | 110 | |
| — | $Varies | 75+ |
Choose from 8 providers that include this biomarker in their panels
Cortisol is a stress &adrenal function biomarker that Stress hormone produced by adrenal glands The normal reference range is anxiety. Regular testing helps track changes and identify potential health issues early.
8 out of 10 major blood testing providers include Cortisol in their standard panels. These include Superpower, Blueprint, Mito Health and others.
For most people, testing Cortisol 2-4 times per year is recommended to establish baseline levels and track trends. If you have abnormal results or are actively working to optimize this biomarker, more frequent testing (quarterly) may be beneficial. Always consult with your healthcare provider for personalized testing frequency recommendations.
The standard laboratory reference range for Cortisol is anxiety. However, many functional medicine practitioners recommend tighter "optimal" ranges for peak health and performance. Your ideal range may vary based on your age, sex, health goals, and other individual factors. Work with a healthcare provider familiar with optimal ranges to determine your target levels.
Most direct-to-consumer blood testing services that include Cortisol provide the physician order as part of their service. However, some states have restrictions on direct-to-consumer testing. Check with your chosen provider about availability in your state and whether they provide the necessary physician authorization.
Essential stress response hormone. Chronic elevation linked to weight gain
This information is for educational purposes only and is not medical advice. Always consult with a qualified healthcare provider about your specific health needs and before making decisions about blood testing.
