FNM Exclusive: 'OITNB' Actress Laura Prepon Reveals Secret Weapon Against Aging in 'The Stash Plan'

"It teaches you to get back in the kitchen," says Prepon of her new book.

Earlier in her career, Laura Prepon had a problem: She was tired, suffering from digestive issues and struggling with her weight — and she was still in her early twenties.

"I realized that there was majorly something wrong," Prepon tells Fox News Magazine. "I had no energy. I was literally like, 'Am I a 90-year-old woman? This is awful! I'm 22 years old!'"

What followed was a decade-long journey to find a cure. According to Prepon, she tried "just about every diet" before finally finding Elizabeth Troy, a nutritionist and health coach who gave Prepon the tools she needed to change her life. And now, Prepon and Troy are sharing what they've learned in their new book, "The Stash Plan."

"It's a lifestyle plan," says the "Orange is the New Black" actress. "It teaches you to get back in the kitchen … and how to really prepare your own meals and build a stash of food twice a week, which is really fast and easy and affordable. And then every morning, you build your meals with it."

In addition to the book's "stash" method, Prepon says there's another key component to the diet that serves as a secret weapon against aging: bone broth.

"Bone broth is a huge part of what really started my healing," says Prepon of the slow-simmered stock/broths that she touts in her book. "When you drink this, it is like the fountain of youth," she adds. "It literally is the cure-all."

Watch the rest of the interview above to learn about the craziest diet Prepon ever tried (pre-Stash), then pick up your own copy of "The Stash Plan" to try out her methods for yourself.