Cameron Diaz has shared her ''life-changing lessons'' in a new wellbeing book.

The 41-year-old actress has compiled her best tips for staying fit and healthy in her first self-penned tome, 'The Body Book', which offers readers a holistic, long-term approach to making consistent lifestyle and food choices.

Recalling the poor diet she followed in her youth, she joked: ''If you are what you eat, I was a bean burrito with extra cheese and extra sauce, no onions.''

In the book, Cameron also stresses the importance of ''sweat[ing] a little every day'' in order to fend off disease and boost energy levels.

Unlike many other celebrities, the sporty 'Charlie's Angels' star believes women should ''embrace'' hunger and gorge on nutrient-dense food.

The book also features advice from Cameron's celebrity pals, including Gwyneth Paltrow and Drew Barrymore.

The blonde took to Twitter to share a make-up free selfie of her proudly holding the first copy of 'The Body Book' last week.

She wrote: ''Her excitement was captured in the caption: 'One of my proudest moments! Receiving the first bound copy of The Body Book!! @thebodybook LADIES!! 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'.''