Fitness Guru Cassey Ho's Heartfelt 'Perfect Body' Video Sheds Body Image Myths

— -- A YouTube video showing how even a fitness guru can be self-conscious about her body has gone viral, with over 1.3 million views in less than a week.

YouTube fitness star Cassey Ho has spent six years creating online fitness courses for her fans with her popular Blogilates channel. With over 2 million followers, Ho thought she was used to online comments both positive and negative.

"In the past few months, online body image negativity has been really running rampant on my channel and other channels," Ho told ABC News, explaining she had commenters say she needed "a bigger thigh gap" or that her "butt is too flat."

"Just recently it was too much and [I] broke down and cried," said Ho.

Ho said that she realized she wanted to do something to show how these comments affected her.

For her "Perfect Body" video, Ho shows herself being inundated with comments after posing for a selfie. She then "Photoshops" herself to have a perfect body, including an unnaturally tiny waist, new eye color and a slimmer jaw line. It's followed with Ho's face reverting back to its natural state and the video ends with the line "What Would You Change About Yourself?"

"The whole point of the video is to show the mean comments and cyber bullying --- it can really change your perception of yourself," Ho said.

A day before the video came out, Ho posted a picture of her "Photoshopped" self to see how people would react. She said she was amazed that the Instagram picture ended up with more than 4,000 comments.

The comments were a "whole myriad," said Ho, ranging from "You’re too anorexic to you have an image disorder" to people saying she had a perfect body.

"It was everything that is wrong with our society in the same photo," she said.

Dr. Laura Caserta, a physician specializing in general pediatrics and adolescent medicine at Rainbow Babies and Children’s Hospital, said she was heartened at the message behind the video.

"Someone is actually bringing out that a lot of these images are not real and a lot of them are Photoshopped," Caserta told ABC News. "Girls and teenagers don’t realize that and set themselves up ... to that ideal when it’s basically impossible."

Caserta said she sees girls as young as 7 or 8 complain about their body after being inundated by unrealistic body images from different media and hopes that Ho showing her insecurities will help others.

"It’s difficult for us," Caserta said of pressures young women face from media and from peers. "There’s a double standard and no matter what you look like, you have some people make some comments."