Primary Causes & Action Plans

Total Testosterone

Your overall testosterone production; primary measure of hormonal status
Total testosterone includes both bound and free testosterone. Men with total testosterone below 500 ng/dL often experience fatigue, muscle loss, and sexual dysfunction. Standard reference ranges (300-1000 ng/dL) are too broad to detect suboptimal function.
Target 600-800 ng/dL (optimal for strength, vitality, sexual function)
Suggested Action Plan

If low, work with an integrative medicine doctor or urologist on testosterone replacement therapy (TRT). Transdermal patches or gels work best. Retest 6-8 weeks after starting treatment and adjust dose to optimize levels while monitoring hemoglobin and prostate health.

Free Testosterone

Biologically active testosterone that actually binds receptors and produces effects
Only a small percentage of circulating testosterone is "free" (unbound); most is bound to SHBG and albumin. Free testosterone is what actually drives muscle growth, sexual function, and mood. A man can have "normal" total testosterone but low free testosterone if SHBG is high.
Target > 8.0 pg/mL (optimal)
Suggested Action Plan

If free testosterone is low despite normal total testosterone, your SHBG is too high. Reduce inflammation, optimize insulin sensitivity, and consider zinc/boron supplementation to lower SHBG. If total testosterone is low, testosterone replacement will increase free testosterone proportionally.

SHBG (Sex Hormone-Binding Globulin)

Binds and inactivates testosterone; high SHBG can produce functional testosterone deficiency
SHBG binds testosterone and reduces its free, bioactive form. Elevated SHBG is common in overweight men, those with insulin resistance, or elevated liver inflammation. High SHBG can produce functionally low testosterone despite normal total testosterone levels.
Target < 40 nmol/L (lower SHBG = more free testosterone)
Suggested Action Plan

Lower SHBG by reducing inflammation, improving insulin sensitivity (low-carb diet, exercise), and losing excess weight. Zinc supplementation can also lower SHBG. Retest in 3-6 months.

LH (Luteinizing Hormone)

Signals the testes to produce testosterone; low LH means primary hypogonadism
LH stimulates Leydig cells in the testes to produce testosterone. Low LH with low testosterone suggests the brain is not adequately signaling the testes (secondary hypogonadism). Normal or high LH with low testosterone suggests the testes themselves are failing (primary hypogonadism).
Target 1.5 - 9.0 mIU/mL
Suggested Action Plan

LH results guide treatment: low LH may respond to hCG injections (which mimic LH) or clomiphene citrate. High LH with low testosterone indicates primary testicular failure requiring testosterone replacement. See a specialist for guidance.

Estradiol

Too-high estradiol in men suppresses testosterone and causes water retention, gynecomastia
Men need some estradiol (converted from testosterone), but excessive estradiol suppresses gonadotropins, lowers testosterone, and causes adverse effects (water retention, gynecomastia, erectile dysfunction). Men on testosterone replacement need estradiol monitoring.
Target 20-30 pg/mL (optimal for men)
Suggested Action Plan

If estradiol is high, reduce obesity (fat produces aromatase enzyme that converts testosterone to estradiol). Limit alcohol, which impairs estradiol metabolism. Consider DIM supplementation (supports estradiol metabolism). Aromatase inhibitors like anastrozole may be needed if very high, but use cautiously as estradiol suppression has downsides.

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Getting Started

1
Get Comprehensive Testosterone Panel

Test total testosterone, free testosterone, SHBG, LH, and estradiol. This full panel reveals whether you have primary (testicular) or secondary (brain) hypogonadism and guides appropriate treatment. Do not rely on total testosterone alone.

2
Interpret Results Correctly

If your total testosterone is 450 ng/dL and your doctor says "you're fine," ask specifically whether that number is optimal for energy, muscle, and sexual function. Many doctors use outdated reference ranges. Seek a specialist if your doctor is dismissive.

3
Start Treatment and Track Response

If testosterone is genuinely low, testosterone replacement therapy is highly effective. Most men feel dramatically better within 2-4 weeks and see muscle gains within 8-12 weeks. Retest 6-8 weeks after starting treatment and adjust dose accordingly.

4
Monitor for Complications

Testosterone replacement can elevate hemoglobin (blood thickness) and hematocrit; annual testing is needed. Prostate should be monitored (PSA, DRE). Some men develop water retention or acne. Work with a knowledgeable physician to manage side effects.

5
Maintain Treatment Long-Term

Testosterone replacement is typically lifelong once started. When treatment is stopped, testosterone levels drop back to baseline within weeks. Once optimized, retest annually and adjust doses as needed to maintain optimal levels.

Why I built this guide.

"Low testosterone is highly treatable. Get tested. Most men feel dramatically better once optimized."

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