Most people try to avoid the cold, but not Wim Hof. Known as “The Iceman” to his 3 million subscribers on YouTube, Hof cold plunges often and steps inside of the freezer he keeps in his backyard every day.

“The first time I went into the cold, I felt [like], ‘This is it.’ Just being, just clarity, and that led me [to] a great, euphoric feeling of not thinking, but feeling,” Hof tells CNBC Make It.

“Then I went back in, and I felt the same. And ever since I have been doing it, I know who I am, what I am.”

For over a decade, Hof has studied the effects of cold exposure therapy on different aspects of mental and physical health.

“We found natural ways to get people back in control over their own mood, and to influence their inflammation, which is disease, using three pillars,” Hof said in an episode of “The goop Lab” with Gwyneth Paltrow.