About Cortisol: Cortisol is the major glucocorticoid (steroid hormone) produced in the adrenal cortex of the adrenal glands. Cortisol is a key stress response hormone – essential for carbohydrate, protein and fat metabolism, anti-inflammatory tasks, blood glucose regulation, and appropriate immune system function.
Cortisol is essential for our active thyroid hormone (Triiodothyronine – T3) ‘expression’ because it up-regulates nuclear T3 receptors within the cells. Cortisol has a quantitative effect by increasing intra-nuclear T3 receptor density (Van Zanden: 2017).
Cortisol production varies throughout the day in a predictable rhythm, termed the diurnal rhythm. Output is highest in the early morning – falling to its lowest concentration at night as Melatonin rises.
People suffering ‘Adrenal Fatigue’ (significant Cortisol insufficiency) exhibit a flattened or inverted Cortisol profile where ‘morning surge’ is absent.
Due to its anti-inflammatory actions, Cortisol insufficiency should always be considered where ‘unequally localised’ inflammatory conditions such as acne, eczema or other skin rashes; ovarian cyst pain, colitis, swollen joints or asymmetrical ear infections persist (Rebic: 2010).
Take-home point: “Inflammatory condition present; think inadequate Cortisol production ….” (Rebic: 2010).
Symptoms of Cortisol insufficiency are:
- Morning tiredness unrelieved by sleep is the classic diagnostic symptom – often with a noticeable energy ‘crash’ in mid or late afternoon.
- An energy surge mid-evening where you feel more energetic to attend to tasks, clear thinking & brighter mood – but you don’t feel the need to sleep until midnight or early hours of the morning.
- Mood disturbance (as anxiety, feelings of continual ‘stress’, restlessness or depressed mood).
- Feelings of light-headedness when standing up; sluggish pupil-contraction when bright light ‘challenged’.
- Seek out salty or sugary, refined foods as quick energy hits.
- ‘Fat’ pads observed as constant puffiness (to varying degrees of intensity) under your eyes.
- Persistent inflammatory breakouts on the skin or joints.
- Younger women may experience quite marked PMS discomfort and/or mood disturbance.
- Reactive hypoglycaemia (Rebic: 2010)
Simple sugars, alcohol, processed white flour are some dietary issues that erode Cortisol levels. Elevated Insulin levels – as found in some metabolic conditions – suppress Cortisol due to the antagonist effect of Insulin on Cortisol.
Pathology testing may be evaluated and/or cross-checked through bloods, 24hr Urine collection or Saliva Hormone assay. Salivary profile is considered more accurate than blood because it indicates what is ‘bio-available’ (ie: accessible) to the body.
Due to its diurnal rhythm, a saliva sample is collected at 6-hourly intervals: 6am, 12 noon, 6pm, and 10pm. This allows assessment of when Cortisol is surging or falling away at correct (or inappropriate) stages of the day.
Although Cortisol insufficiency is sometimes a secondary issue related to disturbed nutritional levels impacting on thyroid-adrenal axis, taking an adrenal support supplement – such as Rhodiola Rosea – is often beneficial for the person’s feelings of general well-being.
Rhodiola is an adrenal adaptogen which neither stimulates nor suppresses but balances Cortisol levels; raising them up when levels are low and settling/calming when levels are high.
Occasionally practitioners will find a patient’s Cortisol is elevated out of range (1). This may be the result of metabolic-hormonal disturbance, physiological or emotional distress from numerous factors including illness or fever. An elevated Cortisol will frequently result in an elevated Reverse T3 (rT3): de-activated T4 thyroid hormone (2).
How elevated Cortisol adversely impacts on thyroid hormone and conversion:
It’s generally understood there are many internal and external factors which will give rise to elevated adrenal Cortisol (CC) levels – temporarily or chronically (3). Increased CC levels are known to have an adversely disruptive effect on thyroid and other hormonal pathways, blocking their expression and being the precursor of numerous disturbances within the body.
Elevated CC specifically interferes with the normal thyroid conversion process by:
- Preventing thyroid stimulating hormone (TSH) signalling from the pituitary gland to our thyroid gland.
- Interferes with the conversion of ‘inactive’ thyroid hormone T4 from converting to the ‘active’ thyroid hormone T3; T3 is recognised as the body’s most important hormone.
- Blocks the thyroid receptors within the cell nucleus from receiving T3 and enable ‘thyroid hormone receptor expression’.
- Erodes the fine gut lining interface increasing the risk of ‘leaky gut’ syndrome.
This is why disturbances of Cortisol often mimics low thyroid function with changes in the following:
- Energy levels leading to fatigue/lethargy.
- Emotional lability, mood disturbance, depression or agitated anxiety.
- Brain ‘fog’ or poor memory recall.
- Changes in normal body weight.
- Thinning of scalp hair density (4).
Melatonin: Melatonin is a rarely discussed or even fully understood hormone that is indispensable to our health and quality of life. Melatonin is a neuropeptide (form of amino acid) secreted principally by the pineal gland within the brain.
Melatonin’s role is to regulate circadian rhythm and induce sleep cycles. It also aids temperature regulation and some hormone cycles. Melatonin secretion is stimulated by darkness and having one’s eyes closed but not being asleep.
Melatonin operates in-rhythm with the Adreno-corticoid hormone Cortisol (CC). In simple terms Cortisol peaks in its diurnal rhythm in the morning – and correspondingly decreases Melatonin levels – to awaken us from sleep. Cortisol gradually decreases over the day (the CC diurnal rhythm), reaching its lowest level in the late evening. Melatonin again begins to rise – and we go to sleep.
Persons experiencing Adrenal Fatigue exhibit a ‘flattened’ – or even inverted Cortisol profile where ‘morning surge’ is absent but occurs in the late evening. An inverted CC diurnal profile will tend to suppress Melatonin – leading to sleep and/or mood disturbance – and ultimately problems with general health.
Humans produce highest levels of Melatonin in childhood – but levels tend to diminish with age.
Melatonin is regarded as the body’s most crucial anti-ageing hormone (Rebic: 2010); a powerful antioxidant, central to immune system integrity – particularly in the prevention of cancer in hormone sensitive tissue (Baratosy: 2010).
Melatonin also exerts an analgesic (opioid-like) effect on the body in chronic pain or inflammatory disease states (Hertoghe: 2006) and helps overcome jet lag.
Melatonin positively influences the effects of our hormones, helping to raise Human Growth Hormone (HGH) and thyroid hormone levels (by increasing T4 – T3 conversion). Adequate levels of Melatonin play a crucial role in reducing disturbance of mood such as depression and anxiety.
Sleep deprivation or interference in natural circadian rhythm for sustained periods of time will severely impact on our health, immediate quality of life – and longevity.
Accelerated ageing, hormonal and metabolic disturbance – such as diabetes, obesity, hypertension; lethargy, lowered immunity, body aches + pains, impaired mental function and hair loss are some of the problems that arise from sleep deprivation and its consequences.
The most restful recovery sleep is between the hours of 9pm to 1am – termed ‘Delta Phase’ (Hywood: 2009). ONE hour of sleep during this period is equal to TWO hours of sleep after 1am.
The body’s physical repair occurs from 9 or 10pm to 2am, whilst immune system and psychological recovery happen between the hours of 2am-6am. Severe headaches and mood disorders may result from lack of sleep through these early morning hours (Rebic: 2010).
How to optimise Melatonin secretion:
- Develop a good sleep routine – aim to be in bed in a darkened room by 10pm.
- Avoid eating heavy (rich or fatty) meals before bedtime as Cortisol levels – which suppress Melatonin secretion – temporarily triple after eating.
- Avoid alcohol, cigarette smoking, caffeine or other stimulant drugs – alcohol and caffeine both inhibit/suppress Melatonin secretion.
- Avoid strenuous physical exercise or activities in the late afternoon or evening.
- Minimise evening exposure to Electromagnetic Radiation (EMR) – power lines, mobile telephones, blue-white fluorescent lighting, electrical appliances such as microwave ovens, televisions, computers, powered alarm clock/radios, personal music devices etc.
It is said we are now exposed to more EMR in one day than those living 50-100 years ago were exposed to in one year. Numerous studies show a direct correlation between EMR exposure and Melatonin suppression (Baratosy: 2010).
Dietary items which enhance Melatonin production:
Because Tryptophan is the precursor of Melatonin (i.e.: synthesised or ‘made from’) – foods which are naturally high in Tryptophan will aid the body’s exogenous Melatonin supply. Some of these foods are chicken, turkey, bananas and milk.
Supplements:
- Fish Oils (EPA/DHA) exert Melatonin-like properties.
- St. John’s Wort can stimulate Melatonin secretion, whilst herbs such as Withania indirectly increase Melatonin by calming excessive Cortisol activity and help in overcoming insomnia.
- (L)-Tyrosine amino acid is the precursor of Tryptophan – which is then the precursor of Melatonin (as referred to above).
According to Chan (2016) a prescription for sub-lingual Melatonin drops is the only form of supplementation effectively utilised by the body.
Melatonin is considered a ‘master hormone’ (Chan: 2016) which profoundly influences endocrine glands and other hormones – as such it should always be prescribed & supervised by a qualified practitioner experienced in hormone therapies.
Testing:
- Melatonin/Cortisol Profile via Salivary Assay is the most reliable method of testing. Due to its circadian rhythm, Melatonin should be collected around midnight (up until 2am) – in darkness – and again the next morning upon rising (6am-8am). The midnight salivary Melatonin reference range is 10-40pg/mL; ‘target’ is 30pg/mL. Morning reference range is 1-3pg/mL (Healthscope Functional Laboratories: 2010).
- 24hr Urinary Excretion for 6-sulfatoxy-melatonin.
Dehydro-epiandrosterone sulphate (DHEA-s) is a male sex hormone (termed androgen) found in the blood of both men and women. DHEA-s aids in developing male secondary sex characteristics at puberty and is a precursor for other sex hormones notably Testosterone and Oestogen.
DHEA-s is produced by the adrenal cortex with smaller amounts being produced by the testes in men and the ovaries in women. It’s regarded as a marker for adrenal reserves and functioning (Lee: 2007).
In rare cases adrenal tumours or adrenal hyperplasia may result in over-production of DHEA-s. Elevated levels may not be noticed in adult men, but in women excess levels may exhibit as amenorrhoea (cessation of menstrual cycle) and visible symptoms of ‘virilising’ (5).
- Blood Cortisol levels >500-600 nmol/L.
- For further information see article ‘Vitamins, Minerals & your Thyroid…’ at hairlossclinic.com.au
- For further information see article The stress – hair loss correlation – hairlossclinic.com.au
- Medical researchers at Harvard University, USA found that persistent physiological stress can induce inactivity in follicle stem cells to prolong the resting phase so (new) hair growth is not initiated.
- Overt male hormone symptoms such as coarsening of the facial skin pores, oily ‘T-zone’, acne and pattern scalp hair thinning.
Copyright Anthony Pearce 2011 (revised April 2026)