40 never looked so good! On Thursday, April, 18, Kourtney Kardashian celebrated her milestone birthday surrounded by family and friends at what appeared to be Kris Jenner‘s lavish L.A. home. Not only was the event a party for the ages — ahem, customized bottles of Don Julio 1942 and a guest list that could rival the Oscars — but the KUWTK star also looked flawless in a tight, black gown with sexy cutouts. 

Speaking of sexy, just ahead of Kourtney’s big day a source revealed exclusively to Life & Style, the proud mama-of-three is embracing her ~kurves~ more than ever. “For the past couple of years, Kourtney has been totally obsessed with being as thin and toned as possible,” the source said. “She’d never miss a workout or cheat on her diet and was super strict about avoiding dairy, gluten and sugar.”

Kourtney Kardashian birthday outfit
Photo courtesy of Kim Kardashian Instagram

Kourtney’s regime was so strict, in fact, that she once admitted on her website that she didn’t even keep dairy, gluten or sugar in the house. No tea, no shade, but we suspect her adorable kiddos, Mason, 9, Penelope, 6, and Reign, 3, weren’t too thrilled about that.

“Recently, she’s really loosened up. She’s treating herself to dessert all the time and thinks nothing of knocking back the drinks on a night out and then loading up on carbs the next day,” the source continued. “Kourtney says it’s all down to turning 40 and that she’s never felt more confident,” the source explained at the time. “She isn’t about to let herself go completely but she’s a lot more relaxed and is embracing her body like never before!”

Kourtney kardashian and friends birthday party
Photo courtesy of Kim Kardashian Instagram

Well, given just how stunning she looked at her birthday extravaganza, we suspect that 40 will be Kourtney’s best year yet — mind, body and soul. Keep slaying, queen!

Can’t get enough celebrity content? Make sure to subscribe to our YouTube channel for fun, exclusive videos with your favorite stars!