Although he had been dead for decades, Jim Morrison said something a few years ago that shocked people. He wasn’t speaking from beyond the grave, but in a long-lost 1969 radio interview, recently re-broadcast. During the conversation, after being questioned about his larger body, Morrison defiantly declared: “Fat is beautiful.”

It’s not difficult to see why this old sound bite was picked up quickly by news outlets and spread across social media. One of history’s biggest sex symbols saying that fat is beautiful was newsworthy. It was a radical statement at the time, and it’s radical now. If the modern-day equivalent of Morrison — whomever that might be — said something fat-positive, you can bet people would pay attention.

As a fat person, I felt a thrill when I heard Morrison’s quote, and I shared the link on Twitter: “Jim Morrison says fat is beautiful.” In under a minute, without anyone having had time to read the interview or even think about it, a friend tweeted back. She was abroad at the time, in another time zone thousands of miles away, but couldn’t resist commenting. She responded immediately that being fat is unhealthy, that it causes high blood pressure and other health problems.

Seeing this response from a friend, I was instantly deflated. Our culture is filled with nothing but contempt for fat people, who are usually portrayed in negative and dehumanizing ways. The Morrison interview was one great thing in a sea of hate, and I was hurt that my friend didn’t recognize what it might mean to me. Instead, she had reached out from the other side of the world to slap me down.

I was still somewhat new to fat acceptance at the time, and I didn’t fully understand why she had responded that way. She was as outraged as if I’d written, “Let’s give heroin to kindergarteners!” Besides her disregard for my feelings, which wasn’t characteristic of her (otherwise, we wouldn’t have been friends), there was another curious thing: She didn’t comment on Morrison’s belief that fat is beautiful. Instead, she raised the issue of health, which was something I hadn’t mentioned. Also strange, she seemed to think she was sharing new information with me. She apparently believed that I, a fat person in my late 30s, had never heard the claim that "fat is unhealthy." That despite the global obesity panic and daily media headlines framing every fat body as a ticking time bomb, I had been skipping along merrily through life, completely oblivious to any of this — until she arrived, superhero cape fluttering in the breeze, to tap me on the shoulder and say, “Haven’t you heard that being fat is unhealthy?”

In the years since, I’ve experienced this response too many times to count. It’s a routine and exhausting part of my life. In 2015, with the release of my novel, Dietland, I began to deal with it on an even larger and more public scale. As I’ve become more involved in the body-positivity movement, I’ve experienced it in multiple countries, in live radio interviews, and in packed auditoriums. The comment sections beneath interviews with me are bursting with it. The reaction to anything fat-positive follows a familiar pattern, and anyone who speaks about fat acceptance knows it well. I call this response “Fat Derangement Syndrome.”

I liken this syndrome to becoming a werewolf. A werewolf, by day, is a normal human, but under the full moon, he turns into a frothing-at-the-mouth beast — a beast that must attack. People with Fat Derangement Syndrome undergo a similar transformation, but their “full moon” is any positive (even neutral) comment about fat. The ideas that it’s okay to be fat, that fat can be beautiful, that humans come in all shapes and sizes, that all bodies have equal value, that fat people can be healthy, and so on, unleash the beast.

Regardless of whether the offending statement is health-related, the response is inevitably health-based. Topics as varied as, say, fashionable plus-sized clothing for teens, a fat triathlete, or Gabourey Sidibe’s latest movie, can trigger it. The most common responses are ones like my friend’s: “Being fat is unhealthy,” or “fat people are at a higher risk for (fill-in-the-blank disease),” often alongside assumptions that fat people have psychological problems and never exercise or eat healthy food. Never mind that fat people have heard these condescending statements countless times before — a person with Fat Derangement Syndrome is suffering from derangement, and therefore must present this information as if it’s brand new. Only then can they retake their human form.