How Britney Spears' Boyfriend Sam Asghari Lost 100 Pounds

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Britney Spears' boyfriend of two years, Sam Asghari, didn't always have a picture-perfect physique.

Britney Spears' boyfriend of two years, Sam Asghari, didn't always have a picture-perfect physique.

In a new interview with Men's Health, the 24-year-old model shockingly reveals he actually lost nearly 100 pounds in 2013, when he made the decision to get serious about his health. He's clearly kept it off since.

Chris Clinton/Men’s Health

“I was eating Doritos for breakfast, fast food, sugar, candy, no protein, a lot of carbs, and drinking sugary sodas,” he says of his former diet. “My nutrition was extremely horrible. The stress and the fear of not going anywhere [in life] combined gave me my depression.”

Asghari was 19 at the time and working three jobs to support himself after getting cut from the University of Nebraska-Lincoln’s Division I football team his freshman year. He admits that when he stopped playing football, he maintained the same diet, leading the 6'2" Asghari's weight to balloon to 290.

“I could either continue going through the same thing or I could give it another 100 percent,” he says of his decision to make big changes in his lifestyle. “I didn’t want to have to deal with that depression and disappointment anymore. I had to restart.”

Restarting meant quitting two of his jobs -- a Best Buy clerk and a nightclub bouncer -- to focus full-time on his gig at Gold's Gym. Asghari was working as a sales clerk at the time and became a personal trainer. He also taught himself about fitness by watching YouTube videos. 

Of course, his diet also had to change drastically to achieve his incredible results. He reveals his meal plan consists of 25 percent protein, 15 percent vegetables and 25 percent complex carbs.

“I allowed myself a $50 shopping budget every single week at the grocery store,” he remembers. “Because of that low budget, I wasn’t able to buy other things that would break [my diet].”

“I didn’t eat for pleasure," he adds. "My eating is now for nutrition and survival."

Though Asghari admits that after getting to just three percent body fat, he became unhealthily obsessed with his weight. He recalls eating just 1,500 calories a day, but burning about 3,000 to 4,000 at the gym.

“When you reach a certain level of accomplishment, you never want to let it go," he explains. "Mentally, you get so paranoid. You think, ‘No, if I eat this, I’m going to go back.' I wasn’t hydrated properly while exercising, and I was passing out. That’s what happens when you’re so lean and you don’t have the right nutrition.”

These days, Asghari tells the magazine that he's maintained a more manageable seven to nine percent body fat, and also gives himself breaks -- especially when on dates with Spears.

“If the ravioli looks good on a date night, I’m eating it,” he says.

Asghari and 36-year-old Spears also enjoy working out together.

“Working out together is always nice and we try to do it a couple times,” he says. “It’s super healthy, mentally and physically. It takes your mind off of everything else.”

He reveals his favorite Spears tune to work out to is "Stronger."

“I put my headphones in and focus on the exercise itself -- that’s therapy for me,” he notes.

On Tuesday, Asghari Instagrammed about his Men's Health interview.

"Sometimes it takes vulnerability in order to inspire a few, my story took hard work, it took the ability to face rejection over and over again and the strength to stand for what I Believe in no matter the circumstances," he wrote. "We are all human, we are not made to be perfect but what we live for is what makes us who we are. Thank you @menshealthmag for helping me tell my story. ... I hope this can inspire a few."

ET recently spoke to Spears about her new unisex fragrance, Prerogative, and she also shared that her priority these days is simply "to be a happy person."

"It's really important to spread joy," she said. "It's contagious. I think that's really sexy for women." 

For more from our sit-down with Spears, watch the video below:

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