Hormones: Part 1 - Know Your Hormones

Discover the hormones within men that can affect their performance, lifestyle and optimise well-being.

Quick disclaimer

This is education and optimisation guidance, not a diagnosis. Hormones are powerful levers. If you have symptoms, abnormal results, or you’re considering testosterone, thyroid medication, aromatase inhibitors, fertility meds, or steroid use, work with a qualified physician/endocrinologist.

Hormones are not just “numbers.” The goal is strong function: libido, energy, muscle, mood, sleep, fertility, metabolism, and resilience.

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1. Testosterone — The Drive, Muscle, Mood & Vitality Hormone

Main functions

Testosterone is the headline male hormone. It supports:

• Libido and sexual performance

• Muscle mass and strength

• Bone density

• Red blood cell production

• Confidence, motivation, aggression/drive

• Mood and mental sharpness

• Fat distribution and metabolic health

• Sperm production indirectly, through the hormonal axis

Typical reference range

Ranges vary by lab, age, country, and assay.

Total testosterone:

• Normal: roughly 300–1,000 ng/dL

• Equivalent: around 10–35 nmol/L

Free testosterone:

• Highly lab-dependent

• Often roughly 50–250 pg/mL, or calculated free T around 200–700 pmol/L

More “optimised” range

For many men, especially 50+, feeling good often lines up with:

Total testosterone:

• Around 600–900 ng/dL

• Or 20–31 nmol/L

Free testosterone:

• Mid-to-upper half of the lab range

• More important than total testosterone if SHBG is abnormal

But remember: a man with total T of 550 and strong free T may feel excellent. Another man with total T of 800 but very high SHBG may feel flat.

What can lower testosterone

• Poor sleep or sleep apnoea

• High body fat, especially belly fat

• Chronic stress

• Excess alcohol

• Opioids, steroids, some antidepressants, glucocorticoids

• Overtraining or extreme endurance work

• Undereating or very low-fat diets

• Vitamin D, zinc, magnesium deficiency

• Insulin resistance/type 2 diabetes

• Ageing

• Chronic inflammation or illness

• Testicular damage, varicocele, chemotherapy

• Anabolic steroid/testosterone misuse suppressing natural production

What can improve testosterone naturally

• Heavy resistance training

• Losing visceral fat

• 7–9 hours quality sleep

• Treating sleep apnoea

• Higher protein intake

• Adequate dietary fats

• Sunlight/vitamin D if deficient

• Lowering alcohol

• Managing stress

• Correcting thyroid, prolactin, insulin, and nutrient issues

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2. Oestradiol / Estradiol — The “Balance” Hormone

Men need oestradiol. Too many men think oestrogen is the enemy. It is not. Too low is a problem. Too high can be a problem. Balance is the goal.

Main functions

Oestradiol supports:

• Libido

• Erectile function

• Mood stability

• Joint health

• Bone density

• Brain function

• Cardiovascular health

• Insulin sensitivity

• Feedback control of testosterone production

Most male oestradiol comes from testosterone being converted by the enzyme aromatase, mainly in fat tissue.

Typical reference range

Using a sensitive male assay:

Oestradiol/E2:

• Normal: roughly 10–40 pg/mL

• Equivalent: around 37–147 pmol/L

More “optimised” range

Many men feel best around:

• 20–35 pg/mL

• Or 70–130 pmol/L

But symptoms matter. Some men do well slightly outside that.

Signs oestradiol may be too high

• Water retention

• Puffy nipples or gynaecomastia

• Emotional volatility

• Lower libido

• Erectile inconsistency

• Fat gain around chest/hips

• Poor response to testosterone therapy

Signs oestradiol may be too low

• Dry joints/aches

• Low libido

• Flat mood

• Poor erections

• Low bone density over time

• Poor sleep

• Feeling emotionally numb

What affects oestradiol

• Body fat: more fat usually means more aromatase activity

• Alcohol

• Liver function

• Testosterone levels

• TRT or hCG use

• Ageing

• Insulin resistance

• Aromatase inhibitors

• Certain medications

• Hyperthyroidism can raise SHBG and alter oestrogen balance

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3. LH & FSH — The Command Signals from the Brain

LH and FSH are pituitary hormones. Think of them as the messages from headquarters to the testicles.

LH — Luteinising Hormone

Main function

LH tells the Leydig cells in the testes to produce testosterone.

Typical reference range

• Normal: roughly 1.5–9 IU/L

More “optimised” range

• Often around 2–6 IU/L, assuming testosterone is healthy

What high LH can mean

High LH with low testosterone often suggests the testes are not responding properly. This is called primary hypogonadism.

Possible causes:

• Testicular ageing/damage

• Mumps orchitis

• Chemotherapy/radiation

• Varicocele

• Genetic conditions

• Chronic toxin exposure

What low LH can mean

Low or low-normal LH with low testosterone suggests the brain/pituitary is not sending a strong enough signal. This is called secondary hypogonadism.

Possible causes:

• Poor sleep

• Obesity

• Chronic stress

• Calorie restriction

• High prolactin

• Opioids

• Anabolic steroids/testosterone use

• Pituitary problems

• Severe illness

• Overtraining

FSH — Follicle-Stimulating Hormone

Main function

FSH supports sperm production by acting on Sertoli cells in the testes.

Typical reference range

• Normal: roughly 1.5–12 IU/L

More “optimised” range

• Commonly 2–8 IU/L, but fertility context matters

What high FSH can mean

High FSH may suggest impaired sperm production or testicular damage.

Common links:

• Low sperm count

• Primary testicular dysfunction

• Varicocele

• Previous anabolic steroid use

• Chemotherapy/radiation

• Genetic factors

What low FSH can mean

Low FSH may occur with:

• TRT or anabolic steroid use

• Pituitary suppression

• High prolactin

• Severe stress

• Obesity

• Caloric restriction

• Chronic illness

Key pattern

If testosterone is low:

• Low T + high LH/FSH = likely testicular issue

• Low T + low/normal LH/FSH = likely brain/pituitary signalling issue

• Normal T + abnormal FSH = possible fertility issue

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4. SHBG — The Testosterone “Transport Truck”

SHBG stands for Sex Hormone-Binding Globulin. It binds testosterone and oestradiol in the blood.

Main function

SHBG controls how much testosterone is “free” and usable.

You can have:

• Normal total testosterone

• But high SHBG

• Result: low free testosterone

• Result: symptoms of low T despite “normal” total T

Typical reference range

• Normal: roughly 10–60 nmol/L

More “optimised” range

For many men:

• Around 20–45 nmol/L

Not too low. Not too high.

If SHBG is high

You may have less free testosterone available.

Common causes:

• Ageing

• Low insulin/very low-carb dieting

• Hyperthyroidism

• Liver disease

• Calorie restriction

• Excess endurance training

• Some medications

• High oestrogen states

If SHBG is low

You may have more free testosterone short-term, but low SHBG often signals metabolic issues.

Common causes:

• Obesity

• Insulin resistance

• Type 2 diabetes

• Hypothyroidism

• Fatty liver

• High androgen exposure

• Inflammation

• Sleep apnoea

Why SHBG matters

Total testosterone alone can fool you.

Example:

• Man A: Total T 700, SHBG high, free T low = may feel tired, low libido

• Man B: Total T 500, SHBG ideal, free T good = may feel strong

Free T and SHBG give the real story.

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5. Prolactin — The Libido Brake Pedal

Prolactin is best known for milk production in women, but men have it too. In men, high prolactin can suppress testosterone and libido.

Main functions

In men, prolactin influences:

• Sexual satisfaction/refractory period

• Dopamine balance

• Testosterone production indirectly

• Fertility

• Immune system signalling

Typical reference range

• Normal: roughly 2–18 ng/mL

• Equivalent: about 40–380 mIU/L, depending on assay

More “optimised” range

For many men:

• Around 4–12 ng/mL

Mild elevations can happen from stress, sex, hard training, or poor sleep before testing.

Recheck before panicking.

Signs prolactin may be high

• Low libido

• Erectile dysfunction

• Low testosterone

• Infertility

• Low mood

• Fatigue

• Nipple discharge, rare in men

• Headaches or visual changes if very high and due to pituitary tumour

What raises prolactin

• Stress

• Poor sleep

• Recent sex/orgasm

• Hard exercise before testing

• Antipsychotics

• SSRIs/SNRIs in some cases

• Metoclopramide

• Opioids

• High TRH from hypothyroidism

• Pituitary adenoma/prolactinoma

• Kidney disease

• Chest wall trauma

• Cannabis may influence levels in some users

Important note

If prolactin is clearly high, especially repeatedly, it needs proper medical workup. Very high prolactin can point to a pituitary issue.

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6. TSH — The Thyroid Control Signal

TSH is not a male sex hormone, but it massively affects male vitality. Thyroid function is the metabolic thermostat.

TSH stands for Thyroid-Stimulating Hormone. It comes from the pituitary and tells the thyroid to produce thyroid hormones, mainly T4 and T3.

Main functions of thyroid hormones

Thyroid hormones influence:

• Energy production

• Body temperature

• Fat loss/metabolism

• Heart rate

• Mood

• Cognition

• Libido

• Testosterone levels

• SHBG levels

• Digestion

• Cholesterol

• Training recovery

Typical reference range

• Normal TSH: roughly 0.4–4.0 mIU/L

Some labs use up to 4.5 or 5.0.

More “optimised” range

Many men feel better with TSH around:

• 0.5–2.5 mIU/L

But TSH must be interpreted with:

• Free T4

• Free T3

• Thyroid antibodies

• Symptoms

• Heart rate

• Body temperature

• Medication status

Do not treat TSH alone.

High TSH can suggest

Usually points toward underactive thyroid/hypothyroidism.

Possible symptoms:

• Fatigue

• Cold intolerance

• Weight gain

• Constipation

• Dry skin

• Low mood

• Brain fog

• High cholesterol

• Low libido

• Higher prolactin sometimes

• Lower testosterone in some men

Low TSH can suggest

May point toward overactive thyroid/hyperthyroidism or too much thyroid medication.

Possible symptoms:

• Anxiety

• Palpitations

• Weight loss

• Insomnia

• Heat intolerance

• Tremor

• Muscle loss

• High SHBG

• Lower free testosterone despite normal total testosterone

What affects TSH

• Autoimmune thyroid disease

• Iodine intake, too low or too high

• Selenium status

• Illness/inflammation

• Severe dieting

• Sleep disruption

• Stress

• Amiodarone

• Lithium

• Steroids

• Dopamine drugs

• Biotin supplements can distort thyroid blood tests

• Thyroid medication timing

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7. Cortisol — The Stress and Survival Hormone

Cortisol is your body’s main stress hormone. It is not “bad.” You need it. But it needs rhythm.

A strong man should have higher cortisol in the morning to wake up and perform, then lower cortisol at night so he can sleep, recover, and produce testosterone properly.

Main functions

Cortisol helps regulate:

• Stress response

• Blood sugar

• Blood pressure

• Inflammation

• Immune function

• Energy availability

• Wakefulness

• Training adaptation

• Fat metabolism

Typical reference range

Depends heavily on time of day.

Morning serum cortisol, around 8 am:

• Normal: roughly 5–25 µg/dL

• Equivalent: around 140–690 nmol/L

Late-night cortisol:

• Should be low

• Salivary cortisol is often used for this

More “optimised” pattern

Rather than one perfect number, think rhythm:

• Morning: healthy rise, often around 10–20 µg/dL

• Evening/night: low

• Good energy in morning

• Calm at night

• Stable blood sugar

• No 3 am stress wake-ups

Signs cortisol may be too high

• Belly fat gain

• Poor sleep

• Waking at 2–4 am

• Anxiety/irritability

• High blood pressure

• High blood sugar

• Muscle loss

• Low testosterone

• Low libido

• Poor recovery

• Cravings, especially sugar/salt

Signs cortisol may be too low

• Severe fatigue

• Dizziness on standing

• Low blood pressure

• Salt cravings

• Poor stress tolerance

• Brain fog

• Unexplained weight loss

• Low blood sugar symptoms

True adrenal insufficiency is a serious medical condition and needs urgent medical assessment.

What affects cortisol

• Sleep deprivation

• Chronic psychological stress

• Overtraining

• Undereating

• Caffeine, especially late or excessive

• Alcohol

• Shift work

• Inflammation

• Depression/anxiety

• Steroid medications

• Cushing’s syndrome

• Addison’s disease

• Blood sugar instability

• Poor morning light exposure

• Night-time screen exposure

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The Big Picture: How These Hormones Work Together

The male hormone axis

Your system runs like this:

Brain → Pituitary → Testes

1. The hypothalamus releases GnRH

2. The pituitary releases LH and FSH

3. LH tells the testes to make testosterone

4. FSH supports sperm production

5. Testosterone converts partly into oestradiol

6. Testosterone and oestradiol give feedback to the brain

7. SHBG controls how much hormone is free and active

8. Prolactin, thyroid, cortisol, sleep, body fat, alcohol, and medications can all interfere

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Useful Testing Notes

If you want meaningful hormone results, test properly.

Best time to test

For testosterone, LH, FSH, prolactin, SHBG:

• Morning blood draw, ideally 7–10 am

• Fasted if possible

• No heavy training the day before

• No alcohol the night before

• Good sleep if possible

• Avoid sex/orgasm before prolactin testing

• Repeat low testosterone before making big decisions

Useful male hormone panel

A solid panel would include:

• Total testosterone

• Free testosterone, preferably calculated

• SHBG

• Albumin

• LH

• FSH

• Sensitive oestradiol/E2

• Prolactin

• TSH

• Free T4

• Free T3

• Thyroid antibodies

• Morning cortisol if indicated

• DHEA-S

• Fasting glucose

• Fasting insulin

• HbA1c

• Lipids

• Liver enzymes

• Kidney function

• Full blood count

• PSA if considering TRT, age-appropriate

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Simple Interpretation Cheat Sheet

Pattern	Possible meaning
Low testosterone + high LH/FSH	Testes struggling to respond
Low testosterone + low/normal LH/FSH	Brain/pituitary not signalling strongly
Normal total T + high SHBG + low free T	Hormones look good on paper, but usable T may be low
Low T + high prolactin	Prolactin may be suppressing testosterone
High oestradiol + high body fat	Aromatase activity likely elevated
Low oestradiol + joint pain/low libido	Oestrogen may be too low
High TSH + fatigue/weight gain	Possible hypothyroid pattern
Low TSH + anxiety/weight loss/palpitations	Possible hyperthyroid or overmedication pattern
High night cortisol + poor sleep	Stress rhythm is off
Low morning cortisol + exhaustion	Needs careful medical evaluation

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Bottom Line

For men over 50, the goal is not to chase one magic testosterone number. The goal is a strong, balanced system:

• Good total and free testosterone

• Oestradiol in the sweet spot

• LH/FSH showing healthy signalling

• SHBG not trapping too much testosterone

• Prolactin not pressing the brake pedal

• Thyroid running the metabolism properly

• Cortisol rising in the morning and dropping at night

Get the basics right first: sleep, strength training, body composition, alcohol control, stress management, protein, sunlight, and metabolic health. Those are the foundations. Then use bloodwork to fine-tune.