There are many food related issues, like anorexia or simply being picky, which are psychologically based. They involve irrational feelings about your food and are, simplistically speaking, remedied by changing mental habits. By contrast, food allergies involve a highly rational fear towards food - some meals really could kill you.
At one point or another, practically everyone I love has poisoned me. Their errors have involved reusing a dirty knife while prepping sandwiches, not reading the ingredients in a spice jar, and assuming salami contained nothing more than dried meat. These were all innocent mistakes and I don’t hold it against my family, but the consequence each time was that I spent a couple hours in the bathroom getting sick. It only took a couple mishaps for everyone to start taking my allergy seriously, but even after that it was a real struggle to keep me fed safely.
During my childhood, we mostly ate at home because it gave my mom better control over what food got in front of me. Butter was not allowed in our house and the cheese was confined to it’s own drawer in the fridge. When we did eat out, I tended to order the same thing over and over again because I knew it was safe. Every new dish felt like Russian roulette and even the repeats were prone to the occasional error.
I had my first cheeseburger when I was a teen. My mother had found a new “dairy free” cheese at the market and was excited to finally share this American tradition with me. A few bites in, my face began turning red and she frantically reread the ingredients, only to find a milk byproduct was on the list despite the package’s labeling. A few years later, a camp counselor unknowingly retried the experiment. In response to my concerns, he reassured me that this was dairy free, vegan cheese…nope.
Over the course of my life, I’ve had over thirty thousand tasty meals without incident, but a few dozen have left me psychologically scarred. When even a well vetted meal might bring hours of pain, paranoia becomes a means of survival. I am, quite rationally, afraid of my food.