The ‘Fat-Girl Algorithm’: How Society Polices Women’s Bodies

In her conversation with Irish Examiner opinion editor Deirdre O’Shaughnessy at Cork World Book Fest, O’Sullivan described the “fat-girl algorithm” as a pervasive force in her life—a set of unspoken rules that dictate how women, especially those in larger bodies, are perceived, judged, and even erased.

“I live in the grip of the fat-girl algorithm,” O’Sullivan said. “It’s not just about how you look; it’s about how you’re allowed to exist in the world. If you’re fat, you’re supposed to be invisible, or apologetic, or constantly striving to shrink yourself—literally and metaphorically. And if you don’t, the world reminds you in a thousand tiny ways that you’ve failed.”

This algorithm, she argues, is not just a personal struggle but a systemic one. It manifests in everything from the lack of clothing options for plus-size women to the way larger bodies are either fetishized or ignored in media. “We’re either the punchline or the cautionary tale,” she said. “There’s no space for nuance, for humanity.”

O’Sullivan’s critique extends to the wellness industry, which she describes as a “predatory” force that profits from women’s insecurities. “The message is always the same: your body is a problem to be fixed,” she said. “And if you can’t fix it, you’re lazy, you’re weak, you’re not trying hard enough. It’s a lie that keeps women trapped in cycles of shame and spending.”

From Poor to Hungry: A Memoir of Survival and Self-Acceptance

O’Sullivan’s first memoir, Poor, was a searing account of her journey from poverty to academia. It won Biography of the Year and Newcomer of the Year at the Irish Book Awards, was translated into seven languages, and was adapted into a sold-out play at Dublin’s Gate Theatre. The book remained in Ireland’s top-ten non-fiction chart for two years, resonating with readers who saw their own struggles reflected in her story.

Hungry, however, shifts the focus inward. While Poor was about external forces—class, addiction, systemic barriers—Hungry grapples with the internalized narratives that shape self-worth. “I wrote Poor to tell the story of where I came from,” O’Sullivan said. “Hungry is about the stories I told myself—and the ones the world told me—about who I was allowed to be.”

The memoir delves into her complex relationship with food, body image, and self-acceptance. Growing up in a household marked by poverty and addiction, O’Sullivan describes food as both a source of comfort and a battleground. “Hunger wasn’t just about not having enough to eat,” she said. “It was about the hunger for love, for safety, for a sense of belonging. And when those things were denied to me, I turned to food—or away from it—as a way to cope.”

Her journey to self-acceptance was not linear. Even as she achieved academic and professional success, she struggled with the disconnect between her public persona and her private shame. “I could stand on stages and talk about inequality, about access to education, about breaking cycles of poverty,” she said. “But when it came to my body, I was still that little girl who believed she was unlovable.”

Cork Roots and the Power of Storytelling

O’Sullivan’s connection to Cork runs deep. During her event at St Luke’s, she revealed that a recent DNA test confirmed her father’s roots in the region. “I discovered I’m pure Rebel,” she joked, adopting the local slang with ease. “Chalk it down, boi.”

The event itself was a testament to the power of storytelling. The former church, with its high ceilings and stained-glass windows, provided an intimate yet grand setting for O’Sullivan’s conversation with O’Shaughnessy. The audience, a mix of ages and backgrounds, listened raptly as she spoke about the themes of Hungry—body image, self-worth, and the relentless pursuit of acceptance.

“Stories like Katriona’s remind us that resilience isn’t just about survival; it’s about reclaiming your narrative,” said O’Shaughnessy. “Her ability to articulate the intersection of class, gender, and body image is what makes her function so vital.”

For O’Sullivan, storytelling is also a form of activism. Through her work with the STEM Passport for Inclusion, she has helped over 10,000 young people from underserved communities access higher education and careers in science, technology, engineering, and mathematics. “Education changed my life,” she said. “But it wasn’t just about the degree. It was about learning to tell my own story—and refusing to let anyone else define me.”

Key Takeaways from Hungry and O’Sullivan’s Work

• The ‘Fat-Girl Algorithm’ is Real: O’Sullivan’s term describes the systemic and cultural forces that police women’s bodies, particularly those who don’t conform to narrow beauty standards. It’s not just about appearance; it’s about how women are allowed to exist in the world.
• Body Image is a Class Issue: Poverty and food insecurity shape how we relate to our bodies. For O’Sullivan, hunger was never just about food—it was about the hunger for safety, love, and belonging.
• The Wellness Industry Profits from Shame: O’Sullivan critiques the wellness industry for perpetuating the idea that women’s bodies are problems to be fixed, trapping them in cycles of spending and self-loathing.
• Self-Acceptance is a Radical Act: In a world that profits from women’s insecurities, embracing your body—flaws and all—is an act of defiance.
• Education is a Tool for Liberation: O’Sullivan’s work with the STEM Passport for Inclusion shows how access to education can break cycles of poverty and empower marginalized communities.

FAQ: Katriona O’Sullivan and Hungry

What is Hungry about?

Hungry is Katriona O’Sullivan’s second memoir, exploring her complex relationship with food, body image, and self-worth. It delves into the psychological toll of living in a body that society polices and the algorithms—both digital and cultural—that shape how women are seen and treated.

How does Hungry differ from Poor?

While Poor focused on O’Sullivan’s journey from poverty to academia, Hungry shifts the focus inward, examining the internalized narratives that shape self-worth. It’s a deeper exploration of the stories we tell ourselves—and the ones the world tells us—about who we are allowed to be.

What is the ‘fat-girl algorithm’?

The “fat-girl algorithm” is O’Sullivan’s term for the unspoken rules that dictate how women, particularly those in larger bodies, are perceived and treated. It’s a systemic force that polices women’s existence, making them perceive invisible, apologetic, or constantly striving to shrink themselves.

What is the STEM Passport for Inclusion?

The STEM Passport for Inclusion is a program led by O’Sullivan that supports young people from underserved communities in accessing higher education and careers in science, technology, engineering, and mathematics. To date, it has helped over 10,000 students.

Where can I buy Hungry?

Hungry is available in bookstores and online retailers, including Gill Books, Amazon, and Book Depository. It is also available as an audiobook and e-book.

Why O’Sullivan’s Story Matters Now

In an era where social media algorithms dictate what we observe and how we see ourselves, O’Sullivan’s work is more relevant than ever. Her memoirs are not just personal stories; they are cultural critiques that challenge the narratives we’ve been fed about class, gender, and body image.

“We’re living in a time where women are told they can be anything—so long as they look a certain way,” O’Sullivan said. “But what happens when you don’t fit that mold? What happens when the algorithm decides you’re not worthy of visibility? That’s the question Hungry tries to answer.”

For readers, O’Sullivan’s story is a reminder that resilience is not just about survival—it’s about reclaiming your narrative. And in a world that profits from women’s insecurities, that’s a radical act.