How 'The Minimalists' use their simple living advice in their own lives and homes

— -- Lifelong friends Joshua Fields Millburn and Ryan Nicodemus say they came from nothing and built successful corporate careers, but after looking around at all of their stuff and taking on debt, they decided to overhaul their lifestyles and eventually became “The Minimalists.”

“The Minimalists,” based around a concept that preaches careful thinking about how to live more with less stuff, is now an entire brand, with a popular podcast, books and a Netflix documentary. But Millburn and Nicodemus got to this point through hard, personal experience.

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The Dayton, Ohio, natives grew up poor -- Millburn said he was on food stamps and government assistance as a kid -- and thought money was the inevitable answer to their early years.

"From an early age, my goal was, ‘We make as much money as I can. I'm going to never be in this position of discontent,’" Nicodemus said.

Both began climbing the corporate ladder, and eventually they were making six-figure salaries and working 70-hour weeks at sizable corporations.

“By the time I was 28, I sort of had everything I ever wanted,” Millburn said. “You know the six-figure salary, the luxury cars, the closets full of expensive clothes and the big suburban house with more toilets than people.”

Nicodemus, too, said at one point he owned a huge three-bedroom, two-bathroom, 2,000-square-foot home that had two living rooms.

But over time, the gleam of their luxury life began to wear off.

"I had a massive amount of debt, six figures worth of debt. Half a million dollars if you count my mortgage and I felt trapped in this lifestyle," Millburn said.

Listen to ABC News' Dan Harris' conversation with The Minimalists (Episode #32) on the "10% Happier" podcast on Apple Podcasts, Google Play Music, TuneIn, on ABC Radio podcasts and under the "Listen" tab on the ABC News app.

Then, in 2009, Millburn’s mother died and his marriage ended in the same month. Shortly after, he said he found the concept of minimalism on Twitter."For me, it all started with a question: 'How might your life be better with less?' And when I was honest myself I realized like the stuff was sort of just the first component," Millburn said. "Like, yes, we can all go home get rid of all of our stuff. You feel a weight lifted right away but you can come home to an empty house the next day and sulk. It can be kind of miserable because that doesn't really address the issue. The stuff is sort of the material manifestation of this internal clutter, emotional clutter, spiritual clutter mental clutter -- whatever you want to call it."

In March 2011, Millburn decided to leave his corporate job. A few months later, Nicodemus was laid off. They then decided to embrace this lifestyle concept of “living minimally” and spent the next few years paring down their possessions, and launched a blog to document their journey.

“It's really about boiling it down to what is essential,” Millburn said. “This word that comes up with me a lot is appropriate. ‘What is appropriate for my life?’ And I'm constantly asking that and it's going to change over time.”

Today, the duo is among the most famous faces of the minimalist movement, sharing their story in speaking engagements across the country with both supporters and skeptics alike. Through their website, books and documentary -- which features ABC News' Dan Harris -- they say they have helped teach over 20 million people how to live with less.

“You know, we see 5,000 advertisements a day,” Nicodemus said. “In minimalism … it's not about deprivation, it's not about giving up on material possessions as much as it is ... shaping our attitudes, shaping our impulses around this consumerist culture that we live in.”

And the guys do practice what they preach. Millburn and Nicodemus showed ABC News their homes in Missoula, Montana.

Millburn said he, his partner Rebecca and their 4-year-old daughter Ella live by the “90-90” rule.

"[I ask myself,] ‘Have I used this in the last 90 days or will I use it in the next 90,’ and if not, we decide to get rid of it," Millburn explained.

Millburn’s bedroom now consists of a bed, an end table, a plant, a fan, a chair and a closet that he shares with Rebecca.

“I used to own so many clothes, I had 12 Brooks Brothers suits,” he said. “I felt compelled to buy more. When I saw something, instead of appreciating it, I felt compelled to bring it into my life without questioning it. I think the difference now is, ‘Can I afford this,’ instead of putting it on a credit card.”

That mentality has drastically reduced the non-essentials, Millburn said, but with having a child, he acknowledged that his family has certain needs that they have to plan for accordingly.

"Minimalism for me, it's never been about deprivation,” he said. “I don't want to deprive myself of something I want to figure out what is essential and then and then eliminate what is not essential."

Millburn said that even his daughter Ella has embraced the minimalist lifestyle.

"Now I have to stop her from donating stuff,” he said. “We're at the kitchen table and she's eating dinner and she's like, ‘Can I donate these carrots?’"

But while minimal living has worked well in his own life, Millburn said it's not his hope to "change anyone else."

"I simply want to share a recipe that worked really well for me not in hopes that other people will replicate it, but in hopes that they will themselves find an ingredient that they can add into their lives and maybe live a bit more intentionally," he said.

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