Somhairlín Ó Cearbhaill, 33, was born into trauma, quite literally.
The daughter of Irish immigrants who struggled with addiction, she came into the world with hearing, learning, and physical disabilities. After the state placed her in foster care, she experienced physical, emotional, and sexual abuse.
She was never a skinny kid, she says, but because her biological family couldn’t afford regular meals — food often came from a gas station — and her foster parents told her she was “thick in the middle,” her relationship with food was rarely healthy.
Ó Cearbhaill, who uses her Irish name professionally but goes by Samantha O’Carroll among American friends, recalls being denied fast food while her foster siblings noshed on burgers and fries. She was “too heavy,” claimed her foster parents, who later adopted her. They’d grow angry when her clothes didn’t fit, put her on diet pills, and banned carbs and sugar.
O’Carroll wanted their acceptance, so she never complained. She felt lucky to have “pretend daughter status,” she says. There were times she’d subsist on a single bowl of applesauce a day to earn their approval.
“I remember my adopted dad being so proud of me,” the Chicago social worker recalls. “I think the only time my adopted dad was proud of me was when I starved myself or when I was working multiple jobs.”
Childhood Trauma and Obesity Risk: What to Know
Fortunately for O’Carroll, she began seeing Liza Suárez, PhD, in her teens. An associate professor of clinical psychiatry at University of Illinois Chicago and director of its Pediatric Stress and Anxiety Disorders Clinic, Suarez continues treating O’Carroll through a variety of techniques.
For sex abuse victims, excessive weight can mean safety. They see themselves as less attractive to a potential attacker, Suárez says. O’Carroll also grew up in households where food was scarce, or denied in a misguided attempt at motivation.
“It wasn’t until the last couple of years that I realized that I turn to food for comfort,” O’Carroll says.
Suárez explained her approach: “When we are trying to help somebody who has traumatic exposure and they have challenges with weight and overeating, it is important to focus on the emotional stressors that might trigger the behaviors rather than the behaviors themselves.”
How Trauma From Your Childhood Affects Your Adult Life
Trauma affects people before they’re born. Stress raises a pregnant mother’s cortisol, which can affect fetal development, resulting in low birthweight, prematurity, and maladjustment of the body’s stress response system, leaving a child hypersensitive to stress.
A useful hormone, cortisol regulates metabolism, inflammation, and the immune system, but when stress is chronic, cortisol can suppress the immune system and spur production of glucose and inflammatory proteins that block insulin uptake, leading to weight gain.
“Early childhood experiences are often stored,” says William Dietz, MD, PhD, director of the STOP Obesity Alliance. “The experience is not transient but becomes in a way embedded in the psyche and behavior of the child — which may or may not lead to obesity, but it’s associated with other risk factors.”
Roughly three decades of research suggest that as traumatic experiences accumulate, so do a child’s chances of adopting risky behaviors, physical inactivity among them. The trauma can alter their cells and the brain regions dedicated to processing emotions, impulses, and fear. Scientists at Harvard University and Massachusetts Institute of Technology are mapping the relationship between illness and so-called “molecular scars” on human cells.
Effects on the brain, hormones, and metabolism “can impact how people experience hunger and satiety, how well they metabolize food, how well their pancreas is functioning. Stress hormones affect our tendency to hold on to calories and put on weight,” says Leslie Heinberg, PhD, a professor of medicine at the Cleveland Clinic Lerner College of Medicine.
Trauma also raises the odds of depression and anxiety, risk factors for obesity. About 2 in 3 women and half of men undergoing bariatric surgery have experienced trauma, Heinberg says. The effects can carry into adulthood, while trauma experienced as an adult can continue disrupting bodily systems.
O’Carroll knows this well. She hasn’t dated in a decade. She tires of explaining why she doesn’t want to be on social media or in photos, so she skips social gatherings. Maintaining friendships is difficult, she says.
“My trauma has definitely followed me into adulthood,” O’Carroll says. “On bad days, I am not myself. My anxiety will prevent me from leaving my home. My depression won’t allow me to have energy to do something I enjoy, like texting a friend back. Struggling with sleep leads me to feeling frustrated with the smallest task or request. I can’t focus long enough to get something done at work.”
Can Childhood Trauma Cause Eating Disorders?
Childhood trauma includes more than abuse and neglect. A family member’s substance abuse, mental illness, or incarceration can traumatize a child. Losing a parent through divorce or seeing their mother treated violently can also take tolls on children, as can environmental trauma such as racism or community violence.
Any of these can heighten the risk of eating disorders, though the mechanisms are unclear, the National Eating Disorders Association says. Studies show people may cope with trauma through food, and researchers posit that trauma exacerbates low self-esteem and poor body image, which can lead to disordered eating. Sex abuse victims are especially prone to eating disorders.
One tricky form of trauma is bullying, says Janet Lydecker, PhD, associate professor of psychiatry at Yale School of Medicine and director of the POWER clinic, which provides cognitive behavioral therapy for teens with disordered eating or eating disorders.
“In some senses, [bullying is] considered to be common or even normal, easily dismissed as part of growing up,” she says. “But we also know there are extremely negative consequences. … For some, it’s going to be absolutely devastating.”
Those can include thoughts of suicide, depression, and pain disorders. Weight is the top reason children are bullied, Lydecker says. One-third of all children experience bullying. The rate is double for children with obesity. Many will have posttraumatic stress disorder, she says.
“What we are looking at is some comfort eating or eating to escape a cognitively terrible experience,” she says.
This can lead to disorders such as anorexia as a child tries to lose weight, she says. When that doesn’t work, the child may instead seek comfort in food, which can lead to more weight gain. This, of course, leads to more bullying.
“It’s a vicious cycle,” Lydecker says. “A negative feedback loop.”
Can Healing Childhood Trauma Help Weight Loss?
Trauma-focused cognitive behavioral therapy is a means of tackling issues that precipitate overweight and obesity. Yale’s POWER program has a version geared to victims of weight bullying.
A trial published last year says such therapy provides “initial evidence that clinically meaningful improvements in patient outcomes were feasible.” Another 2024 study found data connecting child maltreatment and obesity is “robust enough that we suggest that clinicians caring for adult patients with overweight and obesity specifically query about histories of child abuse and neglect.” The American Academy of Pediatrics includes “trauma-informed care” in its guidelines for treating child and adolescent obesity.
Treating trauma is important in optimizing weight loss and helping prevent weight recurrence, Heinberg says, though it doesn’t work for everyone.
O’Carroll wouldn’t be where she is today without trauma-focused cognitive behavioral therapy. Suárez also employs psychoeducation, which helps O’Carroll understand her reactions to trauma and develop coping skills to manage anxiety through relaxation, problem solving, and challenging negative thoughts.
Exposure therapy, in which O’Carroll revisits traumatic memories or experiences to gain mastery of her physical reactions, is important as well. O’Carroll has long been self-conscious about her body, so wearing a “funky T-shirt” or open-toed sandals in a public place helps her confront that discomfort.
“While avoidance is important in the face of true danger and threat, people may engage in avoidance even beyond the point where it provides actual safety,” Suárez says.
O’Carroll’s body mass index was once as high as 47, roughly double what doctors consider healthy. She struggled mightily during an episode last year that led her to cut ties with her adopted parents. She felt she’d lost a second family and, in a way, herself. But Suárez helped her find stability.
She’s since lost 110 pounds. It’s a cause for celebration, but O’Carroll found herself celebrating in another fashion recently: a friend’s wedding. A year ago, she had such severe anxiety the prospect of leaving the house left her panicked. Had she agreed to attend a wedding, which would’ve been unlikely, she would’ve dressed in pants and a conservative top to avoid sticking out. Suárez helped her steel herself.
When her friend walked down the aisle, O’Carroll was there — in a dress.
“Getting ready for the wedding, it was so nice to be a girl and doing my hair and deciding what jewelry should I wear,” she says. “I found a safe space that night. There were other single girls, and we had a great time eating, dancing, taking pictures. I wasn’t triggered.”
She’s since completed her master’s degree in social work at the University of Illinois Chicago and is working on a memoir about her journey with trauma. She gives full credit to Suárez.
“I don’t think I would be alive today without her. Not only do I exist, but the work she has done with me gives me hope that things can get better,” O’Carroll says. “I know the bad days will grow shorter with time because of all the good things I am building with Dr. Liza’s help.”
