Global decline · measured over generations
Male testosterone has more than halved in fifty years.
A pooled analysis of 118,593 men from five countries, presented at ESHRE in July 2026, found average testosterone 54% lower in 2019 than in 1972. The fall is not explained by ageing alone.
−54%
1972 → 2019
Pooled analysis of 118,593 men across the USA, Denmark, Finland, Israel and Brazil, presented at ESHRE in July 2026: average male testosterone more than halved over the period. Presented as a conference analysis, and the largest dataset assembled on the question so far.
−37%
Same age, three decades apart
Perheentupa et al. 2013 (Finland, 3,271 men): men aged 60–69 measured 21.9 nmol/L when born 1913–22, but 13.8 nmol/L when born 1942–51. The gap survived adjustment for BMI.
−22%
MMAS 1987–89 vs. 2002–04
Travison et al. 2007: the population mean fell from 501 to 391 ng/dL at the same age, roughly 1% per year, independent of ageing.
15–39 yrs
It reaches the young
Lokeshwar et al. (NHANES, 1999–2016): total testosterone in adolescent and young adult men fell significantly, and the trend held among men with a normal BMI.
How to read this page
From population figures to your own numbers
This page shows that average male testosterone has fallen across generations, even when men of the same age are compared. That says something about the population, but nothing about you. Follow the steps below from the big numbers to your own measurement.
1. Look at the curves
The charts below show total and free testosterone by age, and where today's average sits against young, healthy men.
2. Read the studies behind them
Every figure comes from a named study from Finland, Denmark, the US and other countries. The study library shows method and limitations.
3. Know the symptoms
Fatigue, low libido and loss of muscle have many causes. The symptom page explains which ones track low testosterone most closely.
4. Take the symptom test
Three minutes give you a first picture of your symptoms before you order anything.
5. Measure your levels
Total testosterone, SHBG and free testosterone are the base panel. Only a measurement shows where you sit.
6. Get a physician's assessment
A physician reads the numbers together with your symptoms. Treatment is only relevant for confirmed deficiency.
Every chart is shown in both the Danish/EU unit (left axis) and the US unit (right axis). Hover any reference point for a fact box with the range, both units, and how it compares historically. A dashed horizontal guide is drawn at that level and marks exactly where the other curves cross it.
Chart 01
Total testosterone by age — healthy young reference vs. today
Left axis nmol/L (DK/EU), right axis ng/dL (US).
Chart 02
Free testosterone by age — the bioactive fraction
Left axis pmol/L (DK/EU), right axis pg/mL (US). Free testosterone is what reaches the receptor. It falls faster than total testosterone because SHBG rises with age.
Free testosterone, symptoms and tissue health
Free testosterone is the fraction available to tissues. It can fall faster than total testosterone because SHBG rises with age.
Upper part of the reference data for healthy young men. A reference position, not a treatment target.
Within the usual laboratory reference range.
Grey zone: symptoms such as fatigue are reported more often here, but the number alone does not make a diagnosis.
Below common laboratory limits. A diagnosis requires symptoms and a repeat measurement.
A public health blind spot
A linear loss with non-linear consequences.
The decline in male testosterone is close to linear, it shows no sign of flattening, and no European government treats it as a measured public health indicator. Insulin resistance, type 2 diabetes, muscle loss, osteoporosis and premature ageing all follow the same curve downwards — in the young as well as the old.
From health problem to security problem
A population whose men are metabolically weaker, less muscular, more diabetic and more fragile in the skeleton is not only a healthcare cost. Recruitment fitness, workforce endurance and civil resilience rest on the same physiology. This is emerging across the Nordics and the entire Western world, and it is politically unmeasured.
Secondary misdiagnosis
When free testosterone is never measured, a deficiency can be missed and its symptoms attributed to other causes such as burnout, depression or poor sleep. Those causes are real too, which is why measurement and a physician's assessment belong together.
What the studies link with low testosterone
Studies such as Dandona, Haider and T4DM link low testosterone with diabetes and bone loss in men. They do not show that treatment would have prevented those diagnoses in every case, so results are read individually with a physician.
Treatment and monitoring
Treatment follows guidelines, with the dose set by the physician.
Guidelines (Endocrine Society 2018, EAU) recommend treatment only when symptoms and repeated morning blood tests confirm deficiency, and aim for levels in the mid-normal reference range during treatment. The physician chooses the product, dose and interval and adjusts them based on symptoms, follow-up blood tests and haematocrit. Levels vary between doses, so the timing of the blood test matters.
Harmonised lower limit for healthy non-obese men aged 19–39 (Travison et al. 2017), used in the Endocrine Society guideline
Mid-normal range, as recommended by the Endocrine Society guideline (Bhasin et al. 2010, 2018)
2.5th–97.5th centile in the Framingham cohort (Bhasin et al. 2011). It describes a population, not a treatment target.
Cohort reference values
| Period | Total T average | Total T, healthy young reference | Free T average | Free T, healthy young reference |
|---|---|---|---|---|
| 1987–89 · MMAS (Travison 2007) | 17.4 nmol/L | up to 41.5 nmol/L in healthy young men | 350 pmol/L | — |
| 1995–97 · MMAS follow-up | 15.6 nmol/L | — | 310 pmol/L | — |
| 2002–04 · MMAS / NHANES onwards | 13.6 nmol/L | — | 270 pmol/L | — |
Sources for this table: population means are the measured MMAS sampling periods (Travison et al. 2007). The healthy young reference column is the Framingham LC–MS/MS cohort of non-obese men aged 19–40 (Bhasin et al. 2011) — a contemporary reference cohort, not a measurement from the era in the first column. Free testosterone values marked as derived are calculated from total testosterone with an age-adjusted free fraction, not separately measured. Across the whole period the largest documented fall is the 54% reported in the ESHRE 2026 pooled analysis of 118,593 men (1972–2019).
Bone, body composition and type 2 diabetes
Observational studies have reported associations between low testosterone, insulin resistance and bone loss; causation has not been proven. Some trials in men with a confirmed deficiency have reported changes in these markers.
Bone density & body composition
Findings reported in treatment and dose-response studies. Individual results vary, and effects on fracture risk have not been established.
Type 2 diabetes & glucose control
Dhindsa and Dandona, Haider and the T4DM trial studied testosterone and glucose control. Observational data show associations; causation is not proven.
Why belly fat locks the imbalance in place
Visceral fat is metabolically active: it secretes inflammatory cytokines and aromatase, which converts testosterone into estrogen. Testosterone falls further, muscle mass and resting metabolic rate drop, and insulin resistance deepens — a closed loop that diet alone rarely breaks.
Why levels fell
Endocrine-disrupting chemicals
BPA and phthalates raise SHBG production, binding and inactivating free testosterone even when total levels look acceptable.
Metabolic dysfunction
Processed food and insulin resistance drive visceral fat, which secretes aromatase and converts testosterone into estrogen.
Chronic stress
Sustained cortisol outcompetes sex hormone production through the pregnenolone steal mechanism.
Sedentary load & sleep debt
Testosterone is secreted largely during deep sleep; shortened, fragmented sleep suppresses the overnight pulse.
The SHBG trap
A man can carry a "normal" total testosterone while high SHBG — which rises with age — drags free testosterone into hypogonadal territory, triggering fatigue, brain fog and metabolic dysfunction. The reverse also occurs: low total testosterone with very low SHBG can remain asymptomatic.
This is why any serious assessment measures total testosterone, free testosterone and SHBG together.
See what we measure