Actress Sarah Michelle Gellar says she doesn't care what people say about smiling causing wrinkles.

The "Buffy the Vampire Slayer" star, 38, has created a new company Foodstirs, which offers convenient and healthy ways to bring families together in the kitchen. While talking to The New Potato site about it, she also shared her beauty secret, reports eonline.com.

"Honestly, I don't care what they say about smiling causing wrinkles, happiness is my key to everything," said Gellar.

"Glowing definitely works from the inside out. That being said, water, keeping yourself moving, and sleep are definitely important."