The topic is trending on the Chinese social media site Weibo, and 110,000 users have posted photos holding pieces of A4 paper, measuring 8.27 inches wide, up to their waists and tagging #I Have An A4 Waist.

If they can hide their waists behind the paper, they consider themselves "fit." One user bragged, "I'm a size smaller than A4. I'm A5."

Critics have posted photos holding the paper horizontally, putting it on small pets, or holding up oversize pieces of poster board instead. "So are they insinuating smaller is better?" one Twitter user wrote. "Not cool to offend the girls who don't measure up in this manner."

While the average healthy waist measurement is 32.5 inches for women and 35 inches for men.

Even some of history's most coveted bodies don't make the cut when an A4-size rectangle is put against their bodies to scale.

We nominated Gigi Hadid, Kim Kardashian, Marilyn Monroe, and Naomi Campbell to step up to the plate. With their diverse body types ranging from super curvy to thin and athletic, very petite to statuesque, and with waistlines ranging from 22 to 26.5 inches, only Marilyn Monroe with her tiny 22-inch waist passed the A4 challenge.