Credit: Stephen Lovekin/Getty Images

Credit: Cameron Diaz on Instagram Photo: Cameron Diaz Goes Makeup-Free

Cameron Diaz's latest book is all about holistic health, fitness, and self-esteem — so it's only "natural" that the 41-year-old actress would promote it sans makeup on Instagram.

The book in question is The Body Book: The Law of Hunger, the Science of Strength, and Other Ways to Love Your Amazing Body — which the Counselor star co-wrote with Sandra Bark — and this December 11 Instagram shows Cameron hugging the book, a gratified smile on her makeup-less face.

"One of my proudest moments! Received the first bound copy of The Body Book!" Cameron writes in the caption. (So for those of you keeping score at home, that would make "Bound 4"?)

"@thebodybook, ladies!" she continues. "I wrote this book for you and your body. And I'm so excited to share it with you! You can pre-order it now. #loveyouramazingbody."

So what's the deal with this book? It starts with Cameron's recognition that  her past habits were not so good for her body. Quoth the Amazon blurb: "Learning about the inseparable link between nutrition and the body was just one of the life-changing lessons that has fed Cameron’s hunger to educate herself about the best ways to feed, move, and care for her body. In The Body Book, she shares what she has learned and continues to discover about nutrition, exercise, and the mind/body connection."

Anything that might get us Cameron's physique is alright by us!