The supermodel and mom, 57, shared a topless photo on Instagram on Thursday, which was briefly taken down for violating the social media platform's guidelines but was later back up.
In the post, Porizkova is wearing lacy underwear and partially unraveled pointed-toe heels. Her stomach is on proud display.
She starts her caption explaining the nuances of comparison and self-doubt, something she has fell victim to herself.
"Did you know we are programmed, as humans, to compare ourselves to others? We can't avoid comparing. But we can control our reactions to the comparisons. I'm a 57-year-old woman, starting my life over. I compare myself to other women my age all the time. When I fit in but somehow feel like I also stand out in a positive way, I feel good about myself. When I fail, I feel ashamed," she wrote.
Porizkova also shared a self-aware tidbit about her inclination to project her own insecurities onto other women when she feels inadequate.
"Shame tells me I'm not good enough. So, my first instinct is to turn it around and shame the person who has caused my shame. If I went with it, I'd be posting snarky shaming comments on other women's feeds," she wrote.
However, Porizkova has found a more positive way to channel these feelings of comparison.
"The antidote to shame, which is all inward and egocentric, is empathy. Facing out, with spiritual generosity. When I recognize my shame: 'I don't look as young, I'm not as rich, or pretty or successful or accomplished or as loved' - as the woman I am comparing myself to, I can turn it around. I can allow her to inspire me instead. I can celebrate and admire, instead of throwing mud. And that's a win for all," she said.
In her caption, Porizkova also embraced her body for all that it's done, including "the crepeyness of my lower belly, which is what happens when you've borne two kids, are thin and 57, regardless of how good your abs are."
Instead, she said she's "decided to think of it as kinda sexy- like rumpled silk sheets instead of a smoothly made bed. It has a history of making love," she added.
This is not the first time Porizkova has taken a bold and somewhat nude stance about her body image on social media.
In May, she took to Twitter to post a partially nude photo addressing critics who consider her too old to post bikini pictures.
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