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For scientists, For Scientific American Science quickly, I'm Rachel Theltenman. Whether it's framed as a carol for fatigue and low libido, or a shortcut to gaining muscle mass,

testosterone replacement therapy or TRT is all over the internet these days.

But how much of the hype is actually backed by science. Here to help us

make sense of the testosterone boom is Stephanie Pappas, a freelance reporter based in Colorado.

Stephanie recently covered the growing popularity and availability of TRT for Scientific American.

Thanks so much for coming on to chat. Thank you. So you recently wrote about testosterone

replacement therapy for Scientific American. For folks who are not on the right part of the

internet to have heard all about this or maybe staying off the wrong parts of the internet,

depending on your perspective, what's going on with TRT right now?

Well, testosterone replacement therapy has become extremely popular. It has been something that's

been in the background for many, many years. Synthetic testosterone was first invented in

1935, but for a long, long time, people thought that testosterone replacement, if it was used for any

kind of symptoms men might be having, that it could cause prostate cancer. And then it was believed

perhaps it could cause heart disease or cardiovascular events like a stroke or a heart attack.

As it turns out, the last few years, we found that it doesn't really cause these really serious

events.

However, a lot less is known about the long-term health impacts.

...