With over 800,000 followers, Essena O’Neill is an Instagram star. But Ms. O’Neill, a 19-year-old Australian, recently surprised her fans by abruptly speaking out against social media.

Changing her Instagram name to “Social Media Is Not Real Life,” Ms. O’Neill has denounced the artificiality of social media, recaptioning many of her old pictures on the site to reveal the painstaking work that went into creating what seemed to be spontaneous moments. It was akin to Beyoncé admitting that she did not, in fact, wake up like this.

In one of the pictures, showing Ms. O’Neill in a bikini, the caption has been rewritten to explain that the photo was taken and retaken over a hundred times. In a smiling selfie, the new caption ends with a disclaimer all in upper case: “There is nothing real about this.”

Image An image from Essena O’Neill's Instagram account.

Ms. O’Neill later removed her Instagram and YouTube accounts from the Internet entirely.

Her awakening to the posturing she says is inherent to social media was accompanied on her page by images and drawings that promote a philosophy opposed to self-promotion.