Gwyneth Paltrow says she's 'so happy to be turning 50' — but admits being a 'mess' when she turned 40

Gwyneth Paltrow will turn 50 on Sept. 27, something the Oscar winner says she's "so excited" about. But the Goop founder admits that she wasn't quite so thrilled a decade ago when her 40th birthday came around.

"I'm so surprised and delighted that I'm not freaked out about it, because when I was turning 40, I was a mess," she tells Sunday TODAY's Willie Geist. "And I was so anxious about it, and I had, like, grief, and it felt, like, really scary. And so I thought, oh boy, 50's gonna feel ... "

She chalks her fear of turning 40 in partly to having "a lot going on in my life that I hadn't resolved yet." At the time, the Emma star was still married to first husband Chris Martin, with whom she shares children Apple and Moses. She and the Coldplay rocker announced their "conscious uncoupling" in 2014, and she has since married TV producer Brad Falchuk while stepping away from Hollywood and building her Goop brand.

Paltrow also acknowledged the "grief" she experienced in terms of aging.

"I think I grieved a lot [about] the physical part," she tells Geist. "I think when you grow up in the culture very much, and [there are] pictures of you everywhere ... and you turn 40 [and] people make such a big deal that you think, oh my God, I'm, you know, over the hill. So there's a kind of grief and letting go of that youth, in a way."

She now sees turning 40 as getting an "amazing software upgrade." She remembers thinking, "this is actually kind of great, and I feel like I can be who I am a little bit more and I have permission."

She adds, "And now I feel like that times a hundred. I just feel, this is who I am, and I really like myself. I really know all of my flaws and I'm really working on them."

And so she isn't fazed by her approaching big birthday.

"I'm so happy to be turning 50. I feel so grateful. I'm so happy that I have my health," the wellness buff says.

"I feel so good!" she adds.

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