Research

Hormonal

In older men (aged 70-89), mid-range plasma testosterone levels (specifically the 2nd and 3rd quartiles, approx. 9.8–15.8 nmol/L) are associated with the lowest all-cause mortality, indicating a U-shaped relationship where both very low and very high levels carry higher risk.

For older men, maintaining testosterone in the mid-range (approx. 10-16 nmol/L) is associated with the lowest risk of death. Neither extremely low nor extremely high levels are optimal. This suggests that avoiding severe deficiency is critical, but pushing levels to the very top of the range may not offer additional survival benefits and could potentially be neutral or harmful.

GoodQualifiesHIGH confidence
Men with total T in the second and third quartiles had significantly lower all-cause mortality than those in the first quartile... consistent with a U-shaped association... an optimal range of circulating total T corresponding to a range of 9.8 to 15.8 nmol/L (282– 455 ng/dL) exists for older men, which predicts survival independent of other risk factors.
Bu B. Yeap et al. · The Journal of Clinical Endocrinology & Metabolism · 2013

Why this rating

Large longitudinal cohort (n=3690), precise LC-MS/MS assays, and extensive adjustment for confounders, but it is observational and cannot prove causation.

Source

In Older Men an Optimal Plasma Testosterone Is Associated With Reduced All-Cause Mortality and Higher Dihydrotestosterone With Reduced Ischemic Heart Disease Mortality, While Estradiol Levels Do Not Predict Mortality

Bu B. Yeap et al. · The Journal of Clinical Endocrinology & Metabolism · 2013

DOI 10.1210/jc.2013-3272

cohort · n=3690Cited 191×
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DOI resolved against Crossref · corpus check 2026-06-10

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