For decades, the dominant clinical concern around testosterone in men has been its potential to fuel prostate cancer growth. This large-scale meta-analysis inverts part of that narrative, suggesting that low androgen levels — not high ones — may be the more meaningful cancer risk signal for overall cancer mortality, with important nuances for prostate cancer specifically.
Drawing on individual participant data pooled across multiple cohorts, the analysis examined associations between circulating testosterone, dihydrotestosterone (DHT), sex hormone-binding globulin (SHBG), luteinising hormone (LH), and cancer outcomes in men. Lower concentrations of total testosterone and DHT were associated with elevated risk of cancer death. Separately, men with mid-range SHBG or LH concentrations showed lower overall cancer risk, while those at the lower end of SHBG or LH distribution faced higher risk of incident prostate cancer — a pattern that diverges from the general cancer mortality finding and adds complexity to the picture.
The finding that hypo-androgenic states correlate with cancer mortality risk, rather than high androgens driving it, is not entirely without precedent. Prior epidemiological work has hinted at a J-shaped or inverse relationship between testosterone and all-cause mortality, and some mechanistic research suggests testosterone supports immune surveillance and metabolic health. However, this meta-analysis is notable for its use of individual participant data rather than aggregate statistics, which improves power and allows for confounder adjustment at the subject level. Key limitations remain: these are observational associations, not causal pathways. Reverse causation is a serious concern — subclinical tumors may suppress testosterone before diagnosis. The prostate cancer findings, with lower SHBG and LH signaling higher incidence, may reflect altered hypothalamic-pituitary-gonadal axis feedback rather than a direct hormonal carcinogenic mechanism. This work is best read as making a case for testosterone and SHBG as prospective cancer-risk biomarkers, not as evidence to alter hormone therapy practice.