If you meet a celebrity, there's one thing you absolutely shouldn't say, according to Ryan Seacrest

It finally happens. You're strolling along the streets of New York, or maybe just through the parking lot of your local Target. And there he is: Your favorite actor. Right. There. In the flesh.

Should you approach [insert celebrity here]? Well, even if the timing is inappropriate, you probably will anyway. Who wouldn't?! Now the question is what exactly to say. Ryan Seacrest is here to help.

"What is the one thing [a fan] should say to wow a celebrity or impress them?" Business Insider recently asked Seacrest.

"Compliments always work," Seacrest replied. "And never tell them they look tired. Because even if they do, they don't want to hear it."

Does he actually hear that often? "Yes. Yes. All the time," he said.

Guess nobody, not even Ryan Seacrest, looks quite so perky when the cameras are off. Now we know.