How Gisele Bündchen Overcame Her Panic Attacks

The supermodel, 38, talks to PEOPLE exclusively about quitting smoking and overhauling her lifestyle through diet, exercise and meditation

Nino Muñoz

After battling panic attacks so intense she considered suicide, Gisele Bündchen set about changing her path — and totally overhauling her lifestyle.

“I was like, ‘Okay, I really have to find help,'” says, the supermodel, 38, in a revealing new interview in this week’s issue of PEOPLE. “It made realize that you cannot be too proud or too feeling like people are gonna judge you or whatever … You gotta ask for help.”

After deciding that she did not want to go the medication route — (“The way I was raised, a pill wasn’t [a solution]. That did make me more anxious just to think that I was gonna be dependent on something else,” she says) — she began focusing on lifestyle changes instead.

Accustomed to working seven days a week, and afraid of saying no to a modeling job, Bündchen says she relied on multiple cups of coffee to get her going in the morning, smoked a pack of cigarettes each day (a mechanism that allowed her to take a breather when she was feeling overwhelmed), and was drinking a bottle of wine each night to relax.

“I gave up everything in one day,” says Bündchen, whose new book, Lessons: My Path to a Meaningful Life, hits Oct. 2. “I was like, ‘That’s it.’ Because I wanted to live. I choose life. I choose to smile again, to be free again. I don’t wanna choose this.”

She adopted a yoga and meditation practice helped her combat stress. “When I started meditating, I started looking at life from a completely different perspective,” she says. “It made me realize that I got into this hamster wheel. My life was playing in front of me like a movie.”

Gisele Bundchen/Instagram

Gisele Bundchen/Instagram

While she privately worked on overcoming her anxiety (“I just told my parents and my agent, and I didn’t even tell my sisters because I was embarrassed by it,” she says) she retreated home to Brazil for 6 months, and also began experimenting with her diet, in the hopes that a nutritional change would have additional impact on her overall health.

“I stopped all sugar. Completely,” she says. “For the first two weeks, I had the worst migraines I’ve ever had in my life. It was a big shock to my body, but it was a three-month kind of cleanse.”

She began running, as a replacement for smoking. “I was filling my lungs, and I was running, I was saying to myself, ‘Smoking is not healthy for me.'”

• For more on Bündchen’s book, pick up the current issue of PEOPLE, on stands Friday.

Gisele Bundchen/Instagram

After a few months, she says she stopped experiencing any panic attacks and had a new outlook on her life — and her health.

“When you’re that age, in your teens in your early 20s, you don’t think about your body as your temple. You think you’re invincible in some way,” she says. “But then when your system is so clean you can feel things so much more. An avocado is suddenly the best thing you’ve ever eaten in your life.”

And she resolved to stick to her new regimen.

“I couldn’t go back to that same life. I didn’t want to,” she says. “My life changed completely that was like one Gisele before age 23 and one after.”

Bündchen’s book (out Oct. 2) is available for pre-order now, and all proceeds will be donated to Project Agua Limpa, a Brazil-based nonprofit organization committed to protecting water sources and sustainability.