Can you touch your belly button by putting your hand round the back and reaching for it in the front? A viral trend called the belly button challenge is taking over the Internet by storm. Basically, you need to wrap your arm around your waist, and touch your belly button.

It's not as easy as it looks.

And not everyone can do it.

You might need a tiny waist and really flexible arms to do it.

The trend then involves users uploading the photos to social media to document their completions or failures.

The whole challenge started on Chinese social media platform, Weibo. Since Wednesday last week, the challenge has generated over 130 million hits.

It apparently originated from an unknown U.S. study that claims women who can touch their belly buttons have good bodies. Those who don't have to lose weight.

We've been trying to find that study, but we can't seem to do so.

So if being able to touch your belly button proves you've got a good body, how about this guy here:

He later admitted it was faked with the help from a friend.

But aside that, even celebrities in China have gotten in on the challenge. This is Yang Mi, a Chinese actress who has nearly 50 million followers on Weibo.

This is Oh Se Hun from Chinese-South Korean boy band EXO getting it done:

But really, it doesn't seem being thin will help you touch your belly button. This user here claims to be 88 pounds, and still can't touch her belly button.

Don't worry if you can't touch it. It's not the end of the world!

Looks like the trend is taking over Instagram too now.