Madden, 36, said he is proud of his wife's courage and strength, reported People magazine.
"I couldn't be more proud of my bad ass wife. She wakes up everyday on a mission to try and make the world a better place. I'm always amazed by the courage, strength and vulnerability she shows, relentlessly encouraging other women to love themselves.
"It has been amazing to get to watch her journey with her new book! #theLongevityBook #April5th @thebodybook @camerondiaz #lovemywife," he captioned a snapshot of the cover of her upcoming book, The Longevity Book.