In 2018, backup quarterback Nick Foles led the Philadelphia Eagles to its first-ever Super Bowl win after defeating the league's defending champion New England Patriots (and the GOAT Tom Brady) 41-33.
Foles was quickly held a hero among sports fans for his victory after having gone under the radar in the NFL for years.
Now the 30-year-old Foles, who has signed a four-year, $88 million deal with the Jacksonville Jaguars, is revealing details about the unconventional health habits he credits for giving him a boost on the field.
"When I first started [in the NFL] I could get away with eating whatever I wanted, my body was just young and could handle it. As my body got older, I started to feel the hits I've taken and the toll that playing football took on my body," Foles tells CNBC Make It.
Foles says things started to change in 2015 when he began following the habits of biohacker and Bulletproof 360 founder Dave Asprey, whose company sells food and supplements that claim brain and energy performance capabilities. Though Asprey does not have a science or clinical background, he says he has spent over $1 million biohacking himself with supplements, devices and neurology equipment to figure out ways to make his body function better and more efficiently. (Some health care professionals have disputed Asprey's claims, saying his methods aren't based on scientific fact.)
Foles announced Thursday he is now a shareholder and partner in Bulletproof 360, which recently expanded its retail footprint to 20,000 new stores including partnerships with Walmart, Target, Publix, CVS and VitaminShoppe. The company has raised more than $68 million since 2012, according to Asprey. Asprey and Foles would not disclose how much of a stake the quarterback has in the company or the amount he is being paid.
But when Foles started implementing Asprey's habits four years ago, he says he was just a fan. He would try hacks Asprey recommended on his radio show, "Bulletproof Radio," and if a habit worked, Foles would keep doing it.
"But I would tweak it to fit me. Some stuff didn't work for my biology, and before long I had this blueprint of what worked for me and it continued to change every day," Foles says.
Foles says he has made several lifestyle changes that have made him feel great and perform "at the top of my game." Here are some of the techniques that Foles says uses to maintain peak performance.
Bulletproof is probably most famous for its butter coffee. Foles says every morning he makes coffee with two tablespoons of what he calls a "highly potent" version of MCT oil (aka, coconut oil), two tablespoons of butter from grass-fed cows and two scoops of collagen protein to create Asprey's signature drink.
Asprey says the coffee concoction can boost metabolism and fat-burning for improved energy. And there is some research to support the idea: The American Journal of Clinical Nutrition found that MCTs, or medium-chain triglycerides found in coconut oil, are metabolized quickly, making them a more effective weight-loss tool than olive oil.
However, experts also warn that the drink is high in saturated fat and may raise cholesterol levels.
Even Foles was leery about trying it (after a family friend told him about it) due to the high levels of fat.
"In college, I took a nutrition class and learned to stay away from fat, so I thought: 'This makes no sense and will make me get fat,'" Foles told MarketWatch.
But he gave it a shot and says he noticed a difference in his energy, which got him hooked.
"I noticed how great I felt cognitively and how my energy [improved]. It wasn't like up and down energy, it was a stabilized energy throughout the day," Foles told Forbes.
He says he would often share the coffee drink with his Eagles teammates before games.
"I made it the morning of the Super Bowl, too. It was part of our tradition," Foles told MarketWatch.
Foles tells MarketWatch he has a hyperbaric oxygen chamber at home, which he uses at least a few days week to help his body recover and to help improve his sleep. It's a technique that has gained a following among NFL players and celebrities over recent years.
Inside the chamber, air pressure is increased to three times higher than normal, pumping high levels of pure oxygen into the lungs. According to the Mayo Clinic, the technique helps to fight bacteria in the body and promote healing, but there are also risks associated with the procedure.
While Foles does credit these habits, as well as taking various supplements, for his enhanced performance, he says shifting his perspective on why he plays football has made the biggest difference in his life.
"A lot of times growing up I was doing everything to win. Winning is sort of intoxicating. I just love to win, but there's also defeat and learning to deal with that. If your identity is in winning you're eventually going to struggle," he says.
After going through the tough times in his career being labeled as just a backup, he learned to change his focus from being on top to simply playing the game for the love of his teammates, family and the sport.
"I've realized that love gives me a greater strength than I quite frankly had for myself."
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This story has been updated.