Paulina Porizkova sleeps free as a bird.

Score one for those who sleep nude. Model Porizkova, 56, revealed she prefers to sleep without clothes while celebrating the true love of her life: her mattress.

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I’m now convinced this is the real reason humans live longer these days,” Porizkova captioned Monday’s Instagram post. “The beauty and wit of middle age is quickly lost if deprived of a comfortable spot to rest ones bones.

On Tuesday, Porizkova shared a one-minute video from her recent campaign with Camilla and Marc.

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Do you know how rare it is to be hired for a campaign that celebrates my age, instead of one in which I’m the token ‘old’ lady?” Porizkova asked. “So rare it only happens once or twice a year. Not only do I adore their clothing; stylish, chic, simple, but also their embrace of a seasoned woman. All you ladies out there, this is how we can change a tiny bit of social conventions at the time…

“By putting our money where we want it to go. Supporting businesses that acknowledge us, women, not just girls,” she explained. “There is clearly no makeup and hair or retouching here. This is what I really look like. And I like it. There is a sort of maturity to me now that commands respect.”