Sophie Ray, 19, of Wales has eaten nothing but cheese pizza for the past eight years, putting her health at great risk and causing concern for her parents.
Ray suffers from Selective Eating Disorder (SED) that leaves her terrified of certain foods and reluctant to try new ones, according to the Daily Mail. SED often starts in childhood but can remain throughout adulthood.
It is not listed in the Diagnostic and Statistical Manual of Mental Disorders, but sufferers and physicians adamantly insist that it is a real problem.
For Ray, the only safe food is cheese pizza. She is able to eat the same type of pizza from a variety of restaurants and says that is the only variation she can tolerate.
"I love pizza," she told the Daily Mail. "Each brand offers a new flavor, but it's all the same food so I don't have to try new foods."
"I began selective eating when I was two," she explained. "My mum said after I was ill I became frightened to eat, I thought food had caused my illness. I began eating cheesy pasta or chips and then moved on to lemon curd sandwiches, which I ate every day for four years."
"I plucked up the courage to try pizza when I was 11, and I've eaten it every day since. Sometimes I have it for breakfast, lunch and dinner," Ray said.
She will often go without meals if pizza is not available.
"The thought of trying other foods makes me very anxious. I feel sick and really clam up. A lot of people think I'm just a picky eater, but SED is a phobia. Asking me to try new foods is like asking someone who hates spiders to hold one."
Part of the fear with SED is that sufferers do not receive the nutrition their bodies need. In Ray's case, her all-pizza diet "does not contain enough vitamins and could shorten her lifespan," says Chris Cheyette, dietician at Kings College Hospital.
The best treatment for SED is cognitive behavioral therapy, say experts. This allows sufferers to retrain their brains and get used to new food. SED is "not trauma and memories that are the problem," according to Dr. Bradley Riemann, director of obsessive-compulsive disorders at Rogers Memorial Hospital in Milwaukee.
"It's more about taste, texture, smell and sight. Exposure works well. Say a person only eats soup; we'll put noodles in it and then work our way up to chicken," Riemann is quoted as saying on the Picky Eaters Clinic Information Education Network.
The Daily Mail reports that Ray visited a specialist but while it helped reduce her anxiety, she is still too afraid to add any new foods to her diet.