"All the interest that used to occupy my mind had been eaten away by my desire to be thin, and it made me miserable," the CW actress says.
"When did being thin become more important than being healthy?" Mendes captioned an Instagram post this week with a picture reading, "Being #DoneWithDieting is about naming the ways that dieting has harmed our mental and physical health."
The actress continued to explain how that thought drove her to pay a visit at her local naturopathic practitioner to discuss her "anxiety around food" and her "obsession with dieting." The doctor advised Mendes to make an effort to focus all of her attention on other subjects and activities.
"I suddenly remembered all the activities I love that used to occupy my time," Mendes said. "At some point in my life, I allowed my obsession with being thin to consume me, and I refused to make room in my mind for any other concerns. Somehow I had stripped myself of all the pastimes that brought me joy, and all that was left of me was my anxiety around food. My passion for education, cinema, music etc. -- all the interest that used to occupy my mind -- had been eaten away by my desire to be thin, and it made me miserable."
Mendes now hopes that her fresh outlook on life will encourage others to remain positive about the body they were given.
"I'm done believing in the idea that there's a thinner, happier version of me on the other side of all the tireless effort," she said. "Your body type is subject to genetics, and while eating nutrient-dense foods and exercising regularly will make you healthier, it will not necessarily make you thinner, and the current system fails to make that distinction."
"I'm sick of the toxic narrative that the media consistently feeds us: that being thin is the ideal body type. A healthy body is the ideal body type, and that will look different for every person. I'm #donewithdieting -- join me in this movement and share your story!"
Mendes' remarks come a few months after the actress joined Project Heal -- an organization that helps people with eating disorders gain treatment.
"I can say from experience that eating disorders are serious mental illnesses," she said in another Instagram posted in October. "Growing up, I watched my big sister suffer from one for many years, and I've experienced periods of my life when I've suffered symptoms as well."