Does keeping your phone in your pocket lower testosterone?

This one has more behind it than the AirPods-brain myth, though it's still not settled. Bryan Johnson states it plainly: carrying your phone in a front pocket can reduce testosterone and sperm count. He cites a meta-analysis of 18 studies finding that close-range phone radio-frequency lowered sperm motility and viability, and his practical takeaway is reassuring: a little distance lowers exposure by orders of magnitude, so the fix is simply not keeping the phone in your front pocket.

Mark Hyman's channel adds a second voice. Fertility specialist Dr. Michael Eisenberg explains that laptops and mobile devices may reduce sperm motility and raise DNA fragmentation through a mix of heat and possible electromagnetic effects, and he recommends insulation or distance. He also flags scrotal heat from laptops and hot tubs as an independent fertility risk, a reminder that lap heat and radiation are two different mechanisms often blurred together.

Two honest caveats keep this nuanced rather than confirmed. First, this evidence is largely associational, and the broader picture on real-world effect size is genuinely mixed. Second, there's a mechanistic counterpoint on Peter Attia's own channel: radiation physician Dr. Sanjay Mehta argues non-ionizing radio-frequency lacks the energy to damage cells. He's discussing cancer fears, not sperm, but it's the reason this topic stays debated.

The takeaway is low-stakes and high-agency: the potential downside is real enough that the experts who cover it recommend creating distance, and the cost of doing so is zero. Keep the phone out of your front pocket and off your lap. This is a fertility and radio-frequency question, separate from the debunked claim that phone radiation harms your brain.