Health experts urge caution over mandatory US military testosterone screenings

US Defence Secretary Pete Hegseth announced earlier this week that all male troops aged 30 and older will be required to undergo routine testing for low testosterone - but medical professionals the BBC has spoken to are urging caution.

Under the new policy, soldiers who are found to have low levels of the hormone will have the option to begin testosterone replacement therapy if needed (TRT).

Doctors want to ensure testosterone levels in a person's blood - which can fluctuate wildly while undergoing treatment - don't drop too low or rise too high, raising the risk of negative side effects.