Dihydrotestosterone & Ageing: Human Studies

Highlights

Key points:

In a lab-standardized comparison of 12 young men vs 11 older men, older men had about 61% lower dihydrotestosterone; the older group also had thicker artery walls and stiffer arteries.¹
In a follow-up study of 1,025 community-dwelling men (median age ~75 years) over about 8.6 years, dihydrotestosterone fell by 7.2% per year on average; testosterone fell by 2.0% per year; luteinizing hormone rose by 7.5% per year.²
In 3,690 men aged 70–89 years, older age, higher body size, and diabetes were linked with lower dihydrotestosterone. In a “very healthy” reference subset (n = 394), the 2.5th percentile for dihydrotestosterone was 0.49 nmol/L.³
In 325 men aged 40+ who self-reported very good or excellent health, testosterone did not drop with age, and dihydrotestosterone slightly increased with age (+0.011 nmol/L per year).⁴
In 2,143 men aged 17–97 years, testosterone related to metabolic features after adjusting for age and body size, while dihydrotestosterone tracked with age and body size and showed limited links to the metabolic score.⁵
Oral finasteride and dutasteride inhibit serum dihydrotestosterone by approximately 60–70% and 85–95%, respectively, depending on dose and duration.
These adult studies indicate that circulating dihydrotestosterone generally declines with ageing (e.g., about −7% per year in very old men), though very healthy cohorts may show minimal change or slight increases.

Limits shown by these papers: most are cross-sectional or observational. Some provide percent change per year or percentile cut-offs, but not full “from–to” values in text. Vascular measures and metabolic features were assessed in only some reports.^1,2,3

Effects on people by health area

Blood pressure and heart

Study title: “Age-related decrease in serum dihydrotestosterone concentration is accompanied by impaired vascular status”

Who they were at the start: 12 young men and 11 older men. Health status and lab methods were standardized for comparisons.
What they did: Single set of blood tests and artery tests.
What the other group did: Younger men served as the comparison group.
Main thing they checked and when: Morning blood levels of testosterone family hormones and artery measures on the same visit.
Main result between groups (plain numbers): Older men had about 61% lower dihydrotestosterone than young men. Older men also had higher carotid intima-media thickness, central augmentation index, carotid–radial pulse wave velocity, and stiffness index.¹
Extra interesting result: Across all 23 men, dihydrotestosterone was lower when artery stiffness markers and C-reactive protein were higher, and was higher when endothelial function markers were higher.¹
Correlation detail: This study suggests that serum dihydrotestosterone showed strong negative correlations with arterial wall parameters: central augmentation index (cAI), carotid-radial pulse wave velocity (crPWV), stiffness index (SI), and carotid intima-media thickness (cIMT), and with C-reactive protein (CRP).
- Central augmentation index (cAI): Extra pressure from reflected waves in the central arteries. Higher cAI means stiffer arteries.
- Carotid–radial pulse wave velocity (crPWV): Speed of the pulse from the neck artery to the wrist artery. Faster speed means stiffer arteries.
- Stiffness index (SI): A number from a finger pulse test that estimates artery stiffness. Higher SI means stiffer arteries.
- Carotid intima–media thickness (cIMT): Thickness of the neck artery wall on ultrasound. Thicker walls can mean artery damage and higher risk.
- C-reactive protein (CRP): A blood marker of inflammation. Higher CRP means more inflammation.
- Plain-language takeaway: When dihydrotestosterone (DHT) was lower, these numbers tended to be higher. High values are not good. They mean the arteries are stiffer: the body's arteries work worse. This is a correlation, not proof that one causes the other. Results need to be replicated in other studies. Still, this is a signal that deserves careful attention. This is what the paper reports for this group.
Side effects: Not applicable.
Why results may differ from other studies: The paper notes age-group comparison with detailed vascular testing; longer follow-up or larger samples might yield different sizes of differences.¹
Real-life meaning (as the paper states it): The authors state that lower dihydrotestosterone in older men was seen together with stiffer arteries and reduced endothelial markers. They do not test what happens if hormone levels change.¹
One short quote: “the most surprising difference was found for DHT concentration, that was as much as 61% lower in aged men.”¹

Hormone levels across ageing

Study title: “Progressive impairment of testicular endocrine function in ageing men: Testosterone and dihydrotestosterone decrease, and luteinizing hormone increases, in men transitioning from the 8th to 9th decades of life”

Who they were at the start: 1,025 community-dwelling older men, median age about 75 years.
What they did: Repeated blood tests over a median of 8.6 years to track hormones.
What the other group did: No separate comparison group; the same men were re-measured over time.
Main thing they checked and when: Testosterone, dihydrotestosterone, estradiol, luteinizing hormone, sex hormone-binding globulin at start and follow-up.
Main result between groups (plain numbers): Average yearly change: dihydrotestosterone −7.2% per year, testosterone −2.0% per year, luteinizing hormone +7.5% per year; estradiol stable.²
Extra interesting result: Larger yearly rises in luteinizing hormone tracked with larger drops in testosterone and dihydrotestosterone, and with poorer scores on some physical tests at follow-up.²
Side effects: Not applicable.
Why results may differ from other studies: This was a long follow-up in very old men; annualized changes reflect late-life trends and may not match younger age ranges.²
Real-life meaning (as the paper states it): The paper describes declines in androgens and rises in luteinizing hormone over time in very old men, and notes links with later physical function.²
One short quote: “Longitudinal change in T was −2.0%/year, DHT −7.2%/year, LH +7.5%/year…”²

Study title: “Reference ranges and determinants of testosterone, dihydrotestosterone, and estradiol levels measured using liquid chromatography-tandem mass spectrometry in a population-based cohort of older men”

Who they were at the start: 3,690 men aged 70–89 years living in the community.
What they did: One morning blood draw per person; a “very healthy” subset was used to define reference ranges.
What the other group did: No separate intervention; comparisons were across age, body size, and health features.
Main thing they checked and when: Morning testosterone, dihydrotestosterone, and estradiol with mass spectrometry; relations with age and health.
Main result between groups (plain numbers): Older age, higher body size, dyslipidemia, diabetes, and higher luteinizing hormone were linked with lower testosterone and dihydrotestosterone. In the healthy reference subset (n = 394, mean age ~76), the 2.5th percentile for dihydrotestosterone was 0.49 nmol/L.³
Extra interesting result: Men with low testosterone or low dihydrotestosterone had higher chances of frailty, diabetes, and cardiovascular disease.³
Side effects: Not applicable.
Why results may differ from other studies: This report focuses on older men only; a “very healthy” subset gives reference cut-offs that may not match general older men with more illnesses.³
Real-life meaning (as the paper states it): The authors propose age-appropriate thresholds to define low hormones in older men.³
One short quote: “the 2.5th percentile… DHT, 0.49 nmol/liter.”³

Study title: “Serum testosterone, dihydrotestosterone and estradiol concentrations in older men self-reporting very good health: the healthy man study”

Who they were at the start: 325 men aged 40+ who rated their health as very good or excellent.
What they did: Nine blood samples per man over three months (fasted and non-fasted mornings) to study day-to-day variation and links with age and obesity.
What the other group did: No separate comparison group; analyses across age and health features.
Main thing they checked and when: Testosterone family hormones at repeated times across three months.
Main result between groups (plain numbers): Testosterone did not vary with age in this select group. Dihydrotestosterone increased slightly with age (+0.011 nmol/L per year). Non-fasted testosterone and dihydrotestosterone were stable over days to three months.⁴
Extra interesting result: Morning fasting raised measured levels by about 9–16% and lowered short-term variability.⁴
Side effects: Not applicable.
Why results may differ from other studies: The men here were exceptionally healthy; obesity and ex-smoking showed stronger links with lower androgens than age itself.⁴
Real-life meaning (as the paper states it): The authors suggest that lower androgens seen in older men may be more about health problems that build up with age than about age alone.⁴
One short quote: “Serum T, DHT and E2 displayed no decrease associated with age among men over 40 years… in very good or excellent health.”⁴

Metabolism and body measures

Study title: “Differential associations of testosterone, dihydrotestosterone and oestradiol with physical, metabolic and health-related factors in community-dwelling men aged 17–97 years from the Busselton Health Survey”

Who they were at the start: 2,143 community-dwelling men aged 17–97 years.
What they did: One blood sample per person; analyses across age, smoking, body size, and other features.
What the other group did: No separate intervention; cross-sectional comparisons across the cohort.
Main thing they checked and when: Circulating testosterone, dihydrotestosterone, and estradiol and how they relate to health features the same day.
Main result between groups (plain numbers): Testosterone related to a clustered metabolic score after adjusting for age and body size; dihydrotestosterone did not track with that score after these adjustments. Dihydrotestosterone related to lower age, lower body size, and lower glucose.⁵
Extra interesting result: Testosterone correlated with dihydrotestosterone and estradiol; relations with cardiovascular disease were limited after adjustment.⁵
Side effects: Not applicable.
Why results may differ from other studies: Wide age span (late teens to very old) and one-time sampling; results reflect cross-sectional links, not changes over time.⁵
Real-life meaning (as the paper states it): The authors note that androgens relate more to age and body size than to heart disease status in this dataset.⁵
One short quote: “In men spanning younger, middle and older ages, circulating androgens are more related to age and metabolic factors than CVD.”⁵

References

· This analysis is for general information only. It is not medical advice and does not give personal recommendations or endorsements. This write-up only restates what the papers comment. Always talk with your healthcare provider before starting any supplement or changing your care. Do not start, stop, or change any medicine because of this text.

· Methodology: We included adult human randomized trials, prioritizing those published in high-ranked, peer-reviewed journals. If fewer than three trials met these criteria, we broadened the journal scope. All numbers and reported side effects are taken directly from the papers. We do not add any conclusions, interpretations or advice.

· This analysis is for general information only. It is not medical advice and does not give personal recommendations or endorsements. Always talk with your healthcare provider before starting any supplement or changing your care. Do not start, stop, or change any medicine because of this text.