Testosterone and combat readiness: what does the evidence really show?

Pete Hegseth, the US defence secretary, recently announced plans to measure testosterone levels in US soldiers with a promise of “ensuring you have the right testosterone levels to operate at your absolute best”. Soldiers found to have low testosterone would be offered treatment, although accepting it would remain voluntary. The announcement has reignited debate about testosterone, masculinity and performance. Here’s what testosterone can – and can’t – tell us about men’s health. Testosterone…