It's such a duh you won't believe it.

Yesterday Kylie Jenner teased the launch of her new website with this before and after picture of her chest with dramatically different looking cup sizes. "Watch my little trick on my app/website," she wrote in the caption.

Well, we fell for the bait (it's research, right?!). In the video on her new site, titled "Kylie Comes Clean: They're Real" (you have to login to see it) Jenner denies having any work done (despite breast augmentation rumors) and reveals her top secret trick: a bra.

"I don't share this with a lot of people, but everyone thinks I've gotten a breast augmentation recently, and I haven't. I just use the Bombshell by Victoria's Secret. It's life-changing. I've gotten all my sisters on it and all my friends. If you want the look of bigger breasts, that's what I do."

Wow, a bra. Groundbreaking, we know. But even we have to admit, that is a dramatic difference.