Even swimsuit models freak out about their bodies. Sailor Brinkley-Cook, 21, is getting real about why she's "been so down on myself recently."

Brinkley-Cook, who has followed her mother Christie Brinkley’s footsteps as a Sports Illustrated swimsuit model, wrote: "Crying about my cellulite, letting the fat on my body ruin my day, getting mad that i’m not as skinny as i once was. The body dysmorphia and left over eating disorder tendencies have been coming in strong. As i come into myself as a young woman my body shifts and changes by the month, the 'control' i felt i once had over it has been completely stripped away from me. Hormones, emotions, growing pains." 

She continued that seeing "perfect" girls on Instagram with "shiny skin with not a bump to be seen, tiny little waist and thighs that look like chopsticks" makes things worse.

"And i compare myself, as if how someone on an app on my phone looks should directly correlate to how I feel about my body? I go to the gym 6 times a week. I fuel my body with beautiful food. I am so (expletive) LUCKY to have two legs and a healthy body that takes me through life. "

She encouraged her 195K followers to "Appreciate yourself. You’re (sic) body is so magical. That’s all. Have a nice day." 

Friends reached out, with Irina Shayk commenting with heart emojis.