Men's testosterone levels fell 54% over five decades, study shows

A meta‑analysis of six long‑term studies presented at the European Society of Human Reproduction and Embryology (ESHRE) conference in London found that average testosterone levels in men dropped by 54 % between 1972 and 2019. The analysis covered more than 118,000 men from Israel, the United States, Brazil, Finland and Denmark.

Researchers linked the decline to rising rates of obesity and diabetes, and also cited possible contributions from endocrine‑disrupting chemicals in everyday products and climate‑related factors. Professor Hagai Levine of Hebrew University described the trend as a “serious crisis in male reproductive health” that warrants urgent attention. Other experts urged caution, noting that methodological differences and unmeasured confounders could affect the estimates.

The findings add to earlier work by the same team that reported a sharp drop in sperm counts over the past 40 years, prompting broader debate about male fertility and public‑health policies.