This post was written by Alex Abel and originally appeared on People.com

For a lot of models, stripping down in front of a whole room of people is just another day at the office. But for Heidi Klum, those intimate moments are about to become a lot more public: The supermodel and TV host just released a brand new coffee table book, Heidi Klum by Rankin, full of nude photos from the past ten years, all taken by photographer (and Heidi's personal friend) John Rankin Waddell. Known as Rankin in the industry, he’s famous for celebrity portraiture—Heidi credits him with creating a comfortability on set that’s unmatched. “A lot of people ask you to do nudes in the industry, but I never really did them with anyone else,” she shared exclusively with People Style. “I’ve known him for 14, or 15 years now which is longer than I’ve had children! I felt very free doing those pictures with him, they were always very art-y. I think nudes are beautiful and I love celebrating women’s bodies.”

At first, they just took the photos for fun after a shoot, but after a few of them, the duo realized they could collect enough for a book down the line and kept it going. The type of shoots ranged far and wide—they shot in exotic locations, on top of crazy sets, and with serious props. Heidi recalls a time during a shoot when she was about 8 months pregnant: “I was seriously craving chocolate so just said, ‘Let’s slime me up with [it]! There are 1-2 photos of this in the book, my boobs were gigantic because when you’re pregnant, everything kind of grows, and I’m just covered in chocolate. It was so fun.”

Rankin

While baring it all might sound insanely intimidating to some, Heidi says she’s totally natural in just her birthday suit. “I feel more comfortable when I’m naked than when I have clothes on,” she explains. “Walking on the runway in lingerie was always easier than doing a show with Zac Posen in a jumpsuit and heels where you have to go out and be all cool. My parents have always been very free as well, maybe I’m just a hippie at heart.”

That feeling extends off-camera too. If she’s home alone, it’s likely she’ll ditch her wardrobe. “It’s not like if you come to my house, I’ll be walking around naked,” she shares. “But if it’s a beautiful, sunny day and I’m in my backyard and there’s no one there? Hell yeah I’m going to take my clothes off. I’d much rather sunbathe naked instead of getting tan lines.”

Rankin

The German beauty tries to do the same when she’s on vacay, but unfortunately, gets caught in the act even when she’s sure she’s alone. “If I’m on a beach and it’s very remote and there are no tourists in sight, then that top is coming off, I’ve always been a top-optional kind of girl. When people see photos of me on the beach naked, that is literally from someone hiding in a submarine who is coming up for air or hiding behind a bush to take photos. I’m not [going topless] because I want to show everyone my boobies, I just didn’t know anyone was watching. I’m still discreet in that sense.”

One thing is for sure—Heidi's confidence is something all women can take a cue from, and as she reveals, it only grows with age. “I feel more confident now than I was in my 20s,” she says. “I’ve had four children, I’ve learned so many things, I feel like I have both feet on the ground and I feel good in my skin, so I don’t mind showing it, you know?”

The book is available for purchase at Bookmarc in New York City, at Walther Koenig and Maison Assouline bookstores across Europe, and at Supra Paris.

BONUS: See some of Heidi's hottest moments with SI Swimsuit!