You have your blood results in hand, and the laboratory says everything is normal. Yet you are exhausted, gaining weight around the middle, losing hair, struggling to think clearly, and waking at 3am every night. This is one of the most common and most frustrating experiences in functional medicine practice. The tests were fine. The patient is not. The problem is almost always the tests that were ordered.
Standard hormone testing in South Africa is designed to rule out disease, not to identify the functional imbalances that drive the symptoms most people actually live with. A TSH that sits at 3.8 mIU/L is technically normal. A ferritin of 12 mcg/L is technically within range. Progesterone tested on day 5 of a cycle tells you almost nothing. The difference between what standard testing measures and what functional medicine testing investigates is the difference between being told you are fine and actually understanding what is happening inside your body.
This guide covers the hormone tests that matter, what each one tells you, when in your cycle to test, and what the functional optimal ranges look like as distinct from the standard laboratory reference ranges used in most South African pathology labs.
Normal on a standard blood test and symptomatic in daily life is not a contradiction. It is a gap between what conventional testing measures and what your body is actually doing. Closing that gap requires knowing which tests to order, when to order them, and how to interpret them in clinical context.
Why standard hormone testing misses most hormonal imbalances
There are three reasons standard hormone testing falls short. First, the wrong markers are tested. A standard thyroid screen orders TSH only, missing free T3, free T4, reverse T3, and antibodies that are essential for a complete picture. A standard reproductive hormone panel orders oestradiol and FSH without progesterone, without testing at the correct point in the cycle, and without assessing the ratio between them.
Second, the wrong reference ranges are applied. Laboratory reference ranges are derived from population averages and are designed to flag disease states, not to identify the functional suboptimal range where most symptomatic people sit. A ferritin of 15 mcg/L is within the standard range at most South African laboratories, yet research consistently shows cognitive impairment and fatigue at ferritin values below 40 to 50 mcg/L.
Third, tests are ordered at the wrong time. Progesterone must be tested at day 19 to 21 of a 28-day cycle, or seven days after confirmed ovulation. Tested on the wrong day it is meaningless. Cortisol is most informative as a four-point salivary assessment across the day, not as a single morning serum draw.
The most important question when reviewing hormone test results is not whether the values fall within the reference range. It is whether the values are optimal for that individual’s symptoms, age, life stage, and clinical picture. These are very different questions.
The complete functional hormone testing guide
| Test | When to test | Why it matters |
|---|---|---|
| Oestradiol (E2) | Day 3 to 5 of cycle or any time post-menopause | Primary oestrogen. Drives uterine lining buildup, bone density, brain function, and skin quality |
| Progesterone | Day 19 to 21 of a 28-day cycle. 7 days post-ovulation | Essential for sleep, mood, uterine health, and GABA-calming of the nervous system. Meaningless if tested at the wrong time |
| Oestrogen-to-progesterone ratio | Calculated from day 21 results | More clinically informative than either hormone in isolation. Identifies relative oestrogen dominance even when individual levels appear normal |
| Testosterone (total and free) | Morning, day 3 to 5 of cycle | Drives libido, energy, muscle mass, and cognitive sharpness in women. Free testosterone more clinically useful than total |
| DHEA-S | Any time of day | Adrenal androgen that reflects adrenal reserve. Declines with chronic stress and age |
| SHBG | Any time of day | Governs how much sex hormone is biologically active. Low SHBG increases free testosterone and oestrogen activity |
| LH and FSH | Day 3 to 5 of cycle | Pituitary hormones that drive ovarian function. Elevated FSH indicates declining ovarian reserve. LH/FSH ratio elevated in PCOS |
| Prolactin | Fasting, morning | Elevated prolactin suppresses ovulation and progesterone. Can be driven by thyroid dysfunction, stress, or pituitary pathology |
| Test | Optimal functional range | Why it matters |
|---|---|---|
| TSH | 1.0 to 2.0 mIU/L | Pituitary signal to the thyroid. Elevated TSH indicates the pituitary is working harder to stimulate an underperforming thyroid. Standard SA labs flag above 4.5 to 5.0 mIU/L |
| Free T4 | 15 to 23 pmol/L | The inactive thyroid hormone produced by the gland. Must be converted to T3 to be metabolically active |
| Free T3 | 4.5 to 6.5 pmol/L | The active thyroid hormone. This is what drives metabolism, energy, cognition, and mood. Often low even when TSH and T4 are normal |
| Reverse T3 | Below 15 ng/dL | The inactive mirror image of T3. Elevated when the body is under stress, caloric restriction, or inflammation. Blocks active T3 from working |
| TPO antibodies | Below 35 IU/mL | Marker of autoimmune thyroid attack (Hashimoto’s). Can be elevated for years before TSH rises. Rarely ordered in standard SA care |
| Thyroglobulin antibodies | Below 20 IU/mL | Second autoimmune marker. Some Hashimoto’s patients are TPO-negative but thyroglobulin-positive |
| Test | Optimal functional range | Why it matters |
|---|---|---|
| Cortisol (4-point salivary) | High morning, low evening curve | Assesses the daily cortisol rhythm rather than a single snapshot. A flat curve indicates adrenal fatigue. An inverted curve indicates circadian disruption |
| Fasting insulin | Below 7 mIU/L | The most sensitive early marker of insulin resistance. Fasting glucose can be normal while insulin is significantly elevated. Most SA labs do not include this in a standard metabolic panel |
| HbA1c | Below 5.4% | Three-month average blood glucose. Standard labs flag above 6.4%. Functional medicine targets below 5.4% for metabolic and hormonal optimisation |
| Fasting glucose | 3.9 to 5.0 mmol/L | Baseline blood sugar. Useful when assessed alongside fasting insulin for HOMA-IR insulin resistance calculation |
| High-sensitivity CRP | Below 1.0 mg/L | Sensitive inflammatory marker. Chronic low-grade inflammation disrupts hormonal receptor signalling across all systems |
| Homocysteine | Below 7.0 µmol/L | Methylation marker. Elevated in B12, folate, and B6 deficiency. Associated with cardiovascular risk and cognitive impairment |
| Test | Optimal functional range | Why it matters for hormones |
|---|---|---|
| Ferritin | 70 to 150 mcg/L | Iron storage. Critical for thyroid function, dopamine synthesis, and cognitive energy. Standard SA lab lower limit of 10 to 15 mcg/L is insufficient for symptom-free function |
| Vitamin D | 100 to 150 nmol/L | Vitamin D receptors are expressed throughout the endocrine system. Deficiency impairs thyroid, immune, and sex hormone function |
| Vitamin B12 | 400 to 700 pmol/L | Essential for myelin, neurotransmitter production, and methylation. Standard labs flag below 140 pmol/L, but symptoms occur well above this level |
| Magnesium (RBC) | 0.85 to 1.0 mmol/L | RBC magnesium reflects intracellular status. Serum magnesium is a poor marker. Magnesium is a cofactor for cortisol regulation, progesterone synthesis, and insulin sensitivity |
| Zinc | 12 to 18 µmol/L | Required for thyroid hormone production, progesterone synthesis, and 5-alpha reductase inhibition |
How to get these tests done in South Africa
Most of the panels above can be ordered through Ampath or Lancet Laboratories across South Africa. Medical aid schemes vary in what they cover. Sex hormone panels are generally covered when ordered by a gynaecologist or general practitioner with an appropriate clinical motivation. Full thyroid panels including antibodies often require a specific request. Fasting insulin and four-point salivary cortisol are less commonly covered and may require private payment.
The most important thing is not simply having the tests done, but having the results interpreted in the correct clinical context by a practitioner who understands functional optimal ranges rather than laboratory reference ranges. A ferritin of 18 mcg/L reported as normal is not the same as a ferritin of 18 mcg/L interpreted in the context of a woman with fatigue, hair thinning, brain fog, and heavy periods.
Getting the right tests done is step one. Having them read correctly, in the context of your full symptom picture and hormonal history, is what transforms a set of numbers into an actionable clinical roadmap.
Medical disclaimer: The information on this page is for educational purposes only and does not constitute medical advice, diagnosis, or treatment. The functional optimal ranges provided are for educational reference only and should be interpreted by a qualified practitioner in the context of your full clinical picture. Individual results vary. If you are currently on medication or receiving treatment for any medical condition, please consult your doctor before making changes to your care. In a medical emergency, contact emergency services immediately.
