Siera Bearchell - LEAD
Credit: sierabearchell/Instagram

Siera Bearchell expected to be busy in the last few days before Sunday's Miss Universe pageant: rehearsing, primping, etc. But what this year's Miss Canada didn't count on was having to defend herself against body shamers.

"I was recently asked, 'What happened to you? Why have you gained weight? You are losing points.' This was a reference to my body of course," she wrote on Instagram last week. "While I am first to say I am not as lean as I was when I was 16, 20, or even last year, but I am more confident, capable, wise, humble and passionate than ever before."

And when a someone alleged that her weight gain showed she lacked the discipline required of a Miss Universe contestant, the 23-year-old law student got real. "To be truthful, I restricted my food intake intensely at previous pageants and was miserable, self-conscious and I never felt good enough," she wrote this week in another heartfelt Instagram post this week. "No matter how little I ate and how much weight I lost, I constantly compared myself to others and felt like I could still lose more. My mental perception did not match the physical body I saw in the mirror.

She went on: "My body is not naturally lean and that's okay. I am healthy. I am fit. I am confident. I am me. This is who I am right now and I'm okay with it, so you should be too. My fellow ladies, remember that true beauty, and validation start from within."

In the end, the criticism only furthered her resolve to change the pageant world from within.

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"In fact, the negativity only fuels my fire to keep working on a platform that so evidently needs to be progressed," she wrote. "This journey has just begun."

Hear, hear, Siera!

You can watch her do her thing in the 2017 Miss Universe competition, Sunday, Jan. 29 at 8 p.m. ET on Fox.