Hormones, Health and the Role of Testing: A Functional Approach for Practitioners

Hormones are the body’s master messengers - microscopic but remarkably powerful molecules that influence nearly every facet of human physiology. From reproduction and metabolism to immune regulation, stress adaptation, and mood, hormones act not as isolated substances but as dynamic signals within a deeply interconnected network.

In clinical practice, we often refer to “hormonal imbalances,” yet this phrase can oversimplify the more nuanced reality. Hormones do not act in a vacuum; they respond continuously to both the internal terrain and external environment. Inflammatory states, psychological stress, nutritional deficiencies, circadian disruption, and toxic exposures all leave their imprint on the endocrine system. When a single hormone within this hormonal web is altered, the effects are rarely contained. Instead, they ripple outward, influencing multiple systems and symptoms.

Recognising these patterns, and interpreting them within the broader physiological context, is the foundation of root-cause, systems-based medicine. It allows practitioners to move beyond symptom suppression and toward restoring balance and resilience within the body’s intelligent design.

The Expansive Role of Sex Hormones

Sex hormones - primarily oestrogen, progesterone, and testosterone - are commonly associated with reproductive health, but their reach extends far beyond fertility. Oestrogen influences mitochondrial function, cardiovascular protection, bone density, and neuroplasticity. Progesterone plays a vital role in mood regulation, neuroprotection, fluid balance, and the maintenance of healthy uterine function. Testosterone supports metabolic flexibility, muscle strength, motivation, libido, and cognition.

In women, the cyclical nature of oestrogen and progesterone shapes not only reproductive health but also brain chemistry, insulin sensitivity, and immune function. These hormones fluctuate predictably across the menstrual cycle, but they also shift with life stages such as puberty, pregnancy, perimenopause, and menopause and are sensitive to psychological stress and systemic inflammation. In men, testosterone levels follow a more stable rhythm but are still vulnerable to environmental toxins, chronic stress, obesity, and insulin resistance.

What is often overlooked is the interdependence between sex hormones and other systems. The thyroid, adrenal glands, liver, and gut all participate in modulating sex hormone levels and activity. Liver detoxification pathways are responsible for clearing oestrogen metabolites, while adrenal hormones such as DHEA influence the availability of testosterone. The gut microbiome, particularly the oestrobolome, regulates reabsorption of conjugated oestrogens. A systems-based understanding reveals that what appears to be an oestrogen excess, for example, may stem from impaired liver clearance or microbial dysbiosis, rather than overproduction alone.

Cortisol and the Physiology of Stress

No discussion of hormones is complete without addressing cortisol, the primary output of the adrenal glands in response to stress. Cortisol follows a diurnal rhythm: highest in the early morning to help us wake and mobilise energy and gradually tapering off toward evening to allow for rest and repair. Under acute stress, this rhythm is beneficial, it fuels alertness, reduces inflammation, and mobilises glucose. However, chronic stress flattens this rhythm, and the protective effects of cortisol give way to dysfunction.

Sustained stress - be it emotional, inflammatory, infectious, or toxic - can dysregulate the hypothalamic-pituitary-adrenal (HPA) axis. The result is often a blunted cortisol awakening response, elevated evening cortisol, or a flattened curve altogether reflecting loss of rhythm. Clinically, these alterations may present as fatigue, poor sleep, insulin resistance, anxiety, or frequent illness. Cortisol also directly affects sex hormones. Under stress, the body prioritises survival over reproduction, diverting precursors like pregnenolone away from progesterone or DHEA synthesis toward cortisol production - a phenomenon sometimes referred to as "pregnenolone steal."

Understanding a client’s cortisol pattern offers far more insight than a static serum cortisol level ever could. It reveals not only the presence of dysregulation but also where the client is in the stress response continuum - from hyperarousal to burnout.

Melatonin: Beyond Sleep

Melatonin, often pigeonholed as the "sleep hormone," plays a far more expansive role in human physiology. Secreted by the pineal gland in response to darkness, melatonin orchestrates circadian rhythm and prepares the brain for restorative sleep. However, it also acts as a potent antioxidant, supports mitochondrial function, and modulates the immune response.

In modern life, melatonin secretion is frequently disrupted. Blue light exposure from screens, inconsistent sleep patterns, shift work, and chronic stress all impair melatonin production. The result is more than just insomnia; it is a disruption of the delicate balance between the sympathetic and parasympathetic nervous systems. This imbalance affects heart rate variability, immune surveillance, tissue repair, and even gut permeability. Furthermore, melatonin interacts with other hormones - supporting progesterone, tempering cortisol, and influencing reproductive signalling. A client presenting with insomnia, low mood, or immune dysfunction may benefit as much from melatonin support as from stress management or sex hormone balancing.

Environmental Hormone Disruptors

Hormonal health cannot be fully understood without considering the environment in which the endocrine system operates. Endocrine-disrupting chemicals (EDCs) have become ubiquitous - found in plastics, receipts, food packaging, cosmetics, and cleaning products.

Compounds like bisphenol A (BPA), phthalates, parabens, and certain pesticides mimic or block hormone receptors, interfere with detoxification enzymes, and alter gene expression.

BPA, for instance, mimics oestrogen and binds to oestrogen receptors, often displacing natural oestrogens or triggering inappropriate signalling. Phthalates suppress testosterone synthesis, impacting male fertility and contributing to metabolic disease. These disruptors are particularly problematic during critical developmental windows such as in utero, during puberty, or throughout perimenopause when hormonal regulation is especially sensitive.

Their presence is associated with a host of modern disorders: PCOS, endometriosis, early puberty, thyroid dysfunction, obesity, and even hormone-sensitive cancers. Importantly, many of these chemicals are detectable in blood, urine, or even dried urine testing, and reducing exposure can be a significant therapeutic intervention.

Recognising Hormonal Dysregulation in Clinical Practice

Hormonal dysregulation rarely presents with textbook clarity. Instead, clients may describe symptoms such as fatigue, anxiety, irritability, brain fog, weight gain, or low libido. These symptoms are often vague and overlapping, and may be wrongly attributed to aging, psychological stress, or lifestyle habits alone.

A woman with oestrogen dominance may experience mood swings, breast tenderness, heavy or irregular cycles, and migraines. Yet she may also have poor liver detoxification or gut dysbiosis. A man with low testosterone may report loss of motivation, increased abdominal fat, and poor muscle tone yet stress and poor sleep may be the true drivers of his hormonal shift. The key is pattern recognition: understanding how symptoms map onto hormonal pathways, and which upstream systems - adrenals, liver, thyroid, or microbiota - may be influencing those patterns.

In this context, a thorough clinical history is just as important as any lab test. Menstrual history, stress exposure, sleep quality, dietary habits, toxin exposures, and medication use all offer critical clues. When hormonal testing is used thoughtfully, it can validate clinical suspicion and guide targeted intervention.

The Value of Advanced Hormone Testing

Advanced hormone testing allows practitioners to see beyond surface-level values. Rather than asking “How much hormone is present?”, we can ask, “How is this hormone being used, metabolised, and cleared?”

Salivary testing is particularly useful for evaluating diurnal cortisol patterns and bioavailable levels of hormones such as progesterone and DHEA. Dried urine testing, such as that offered by ZRT Laboratories, adds a deeper layer of insight measuring not only parent hormones, but also their metabolites. This is crucial when evaluating risk factors and therapeutic strategies.

For example, oestrogen metabolism can be accessed via the ratios of 2-hydroxyestrone, 4-hydroxyestrone, and 16α-hydroxyestrone. A dominance of the 4-hydroxy pathway may signal increased risk for DNA damage and oestrogen-sensitive cancers, especially when methylation is impaired. Similarly, testosterone metabolism via 5α- and 5β-reductase pathways can indicate androgenic activity and guide intervention in conditions like PCOS or hair loss.

Cortisol and cortisone measurements throughout the day reveal HPA axis dysfunction more clearly than a single blood draw. Patterns such as high evening cortisol or a flat cortisol curve inform the use of adaptogens, timing of exercise, or the need for circadian retraining.

Importantly, ZRT’s panels also include markers such as BPA, offering practitioners a tangible measure of environmental burden - a key piece of the puzzle when dealing with chronic, unexplained symptoms.

Integrating Testing into Functional Care

While advanced testing provides critical data, it should always be interpreted in context. Lab values are not isolated truths; they reflect a moment in time within a dynamic system. No test can replace clinical curiosity, detailed case-taking, and thoughtful follow-up.

The goal is not to chase numbers into perfection, but to understand the story the body is telling and to co-create a therapeutic strategy that addresses both symptoms and the system that generated them. Advanced hormone testing, when used within a functional framework, offers a pathway to clarity, personalisation, and transformation. It equips clinicians with the tools to listen more deeply to the body’s story and respond with strategies that are as nuanced and intelligent as the system they are meant to support.

This often includes nutrition, sleep, nervous system regulation, targeted supplementation, environmental detoxification, and sometimes hormone replacement or herbal therapy. In many cases, healing does not require aggressive intervention, but rather restoration of rhythm: regular sleep, predictable meals, gentle exercise, time in nature, emotional connection, and the removal of physiological interference.

Hormone testing with Colab Services:

Dried Urine Testing

Z721 Hormone: Advanced Metabolites: Complete hormone metabolite panel, including additional metabolites in the MEO pathway, BPA marker and results return within 7 days. We can also offer any sex hormone combination via blood testing so you can curate your own stand-alone panel, or create a contextual panel to complement dried urine testing.

Z725 Menstrual Mapping - The 28 day hormone assessment test

Blood Testing

Q402- Thyroid Elite Panel- Includes Reverse T3, TSH, T4 (thyroxine), T4 (free), T3 uptake, TPO abs, Thyroglobulin ab, iodine and selenium.

Blood Spot Testing

Z705 Thyroid Advanced Bloodspot – Includes TSH, TPOab, FT3, FT4, Thgn, T4

Z703 Female Bloodspot 1 - SHBG, T, Prog, E2, DHEA-S, Cortisol

Saliva Testing

Z710 - Adrenal Profile Including CAR

Z713 - LCMS Saliva Steroid Hormone Panel includes: Estradiol, Estriol, Estrone, Pregnenolone, Progesterone, Allopregnanolone, 17-OH Progesterone, Androstenedione, Testosterone, DHT, DHEAS, 7-keto, DHEA, Ratio: DHEA/7Keto DHEA, 11-Deoxycortisol, Cortisol, Cortisone, Corticosterone, Aldosterone, Melatonin, Anastrozole, Finasteride, Letrozole