One's first reaction to glamorous Hollywood star Cameron Diaz releasing a book on how to “age better” might be the assumption it contains only three words: ‘Have good genes.’

But in a blog post promoting the April release of The Longevity Book, the actor says people should look “beyond what’s superficial… it’s more than wrinkles, grey hairs and sagging”.

In a post titled Embracing Age & Celebrating Life with Cameron Diaz, she writes: “I’m interested in engaging us all in a conversation: one that is about regeneration, about new ways to talk to each other and ourselves about the ever growing, changing, and aging state of being a human.

“This time I want to talk about one of the biggest taboos in our society. AGING […] I wanted to write this book so that we could understand what aging really is. And what I found was aging isn’t about getting old it’s about LIVING… and I want you to live the happiest longest and healthiest life possible.”

Diaz, 43, has long been a proponent of living healthily, bringing out The Body Book in 2013, and making a point of letting fans see her without perfect Hollywood make-up and lighting on her Instagram account, previously thanking a magazine for not airbrushing her “laughlines” on a cover.

And as someone who started out modelling at the age of 16 before transitioning to acting with The Mask at 21, maintaining a presence in industries obsessed with appearance and rarely kind to women over a certain age for 27 years, perhaps it makes sense she's thought more than most about ageing.

She continues: “I want to let you all off the hook of thinking you need to fit in to one picture of health in order to achieve wellness. From thinking that you have to go out in search of things externally, into a world of confusing messages that tell you how you should LOOK, and what you have to buy and buy into to do so. I say let’s take this conversation beyond what’s superficial… it’s more than wrinkles, grey hairs and sagging – it’s about your cells and what happens deep within them […]

“Learning that you can age well, will actually help you to age better. If you understand how your body works then you can take action to help keep it in the best possible condition so it can carry you through a long and beautiful life.”

“So let’s start celebrating...and stop punishing ourselves for not looking a certain way, and instead holding ourselves accountable for actually taking care of ourselves inside first, knowing the results on the exterior will be a shining side effect.”

Images: @camerondiaz