Transcript for Testosterone: a Fountain of Youth for Men?
And now we take a look into a kind of secret society. Baby boomers ready to do whatever it takes to stay young. Since 2006 prescriptions of testosterone have doublinged since 2006. And they're expected to triple again in the next 5 years. Abc's neal karlinsky tells us who is doing this and at what risk. Reporter: They are a mountain of baby boomers. It feels like I got my mojo back. I think every guy over 50 should be doing it. Reporter: Putting co-workers on notice. I mean honestly, I like looking at myself in the mirror. I look freaking awesome! Reporter: He says the secret is testosterone -- which 57-year-old ceo chris running showed us as if it was no different than a glass of orange juice. Reporter: So that's it? Twice a week? Yeah. Our generation is trying to stay as young as we can for as long as we can. Reporter: You see it in those ads --appealing to the 70 million boomer men unwilling to fade quietly into old age. Reporter: A boost of testosterone, long the illegal drug of choice in sports is being touted as a virtual fountain of youth. And just a prescription away. I've gone from a 38 waist, relaxed fit jean to a 34 slim waist fit. Reporter: In the three years he's been taking "t," chris says he has transformed himself into a younger man. Two homore work per day, 30 pounds of fat, gone. And muscles. Bulging muscles, more impressive THAN ANYTHING HE HAD IN HIS 20s. You notice the physical change too? He talked about 30 pounds? Muscle? He looks great, he's in great shape. It's been a very positive change. Reporter: We wondered, can it really be that simple? Dr. Karron power says, "yes." And I hear a lot of men come in and talk about the young guys coming in and that they feel the challenge. Reporter: Is that cheating? If your levels are low and they bring you back to a normal level, or an optimal level, then aren't I just leveling the playing field? Reporter: So, what is normal for what age? The average 20-year-old's testosterone levels can reach as high as 1080, but as you age, the levels drop without drugs. By age 60, the average is only 720. So, is it right to pump testosterone up to the levels of a much younger man -- a level that in many cases more than doubles a man's testosterone? Not so fast says dr. Edmund sabanegh, an expert in testosterone at the prestigious cleveland clinic. He's worried about the wave of boomer men using "t" as a "fountain of youth." To stay artificially young. Right now, we don't have guidance in the medical research that suggests it's safe to stay on those levels. Reporter: And there are serious possible side eff too. Testosterone has been linked to blood clots, liver damage, and -- some think you could be playing russian roulette with prostate cancer. "The new england journal of two percent of men over 40 should be getting boost at all. Chris running and the growing number of boomers just like him aren't worried. Bottom line, you're sold? I'm absolutely sold. I will never not do this. Reporter: Risky or not, he says slowing down so the next generation can move up -- is not an option. And coming up right here on "world news," close encounters
This transcript has been automatically generated and may not be 100% accurate.