Amy Berkowitz's chronic pain began in her shoulder. Then, she experienced the same dull ache all over. At 23 years old, she eventually came to feel overwhelmed by these full-body pangs. "Every morning I wake up feeling like I was run over by a truck," Berkowitz writes in her new book, Tender Points. "I feel like I've been hit by a bus. I wake up feeling like I got whiplash. I wake up feeling like I slept on the floor."

Named after the 18 points that people suffering from fibromyalgia find painful when pressed—"two at the bottom of the neck just above the collarbone, two just below the center of each collarbone, one on the crease inside each elbow, two more on the inside of each knee, on the back of the body, two at the bottom of the neck, one above each shoulder blade and just inside each shoulder blade, two on either side of the lower spine, two more on the outer part of each hamstring"—her book details with lyrical precision what it's like to live with the chronic pain that characterizes the disease, and what it's like when no one believes you're hurting.

Affecting between two to four percent of the population, fibromyalgia is the label that encompasses ongoing bodily pain, fatigue, non-restful sleep, and brain fog. Women are diagnosed with the condition seven times more than men. The disease was first identified in the 1990s as a catchall for patients who reported experiencing life-disrupting discomfort but who seemingly had "nothing wrong with them," pathobiologically speaking. To be diagnosed, a patient must exhibit pain in 11 of the 18 tender points when pressure is applied. Until recently, however, women with this pain of no objective origin have often been told that it is all in their heads. Only a few years ago, the New York Times ran piece on the condition with the headline, "Drug Approved. Is Disease Real?" and quoted papers that questioned the legitimacy of fibromyalgia as a medically recognizable illness.

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Fibromyalgia, as a diagnosis, is indeed complicated, but those who suffer from widespread pain certainly aren't just imagining it. Patients diagnosed with the condition experience it in varied ways. Some live with manageable pain and are able to go about their days normally, using different therapeutic techniques. Others have had to stop working, cut back on activity, or have lost mobility completely. With such a vast range of cases, it's clear that fibromyalgia is not a specifically defined illness—but the diagnostic label has anecdotally helped the comparatively large population of women who have been historically met with skepticism for their very real pain. In her sociological study of the condition, Kristen K. Barker conducted multiple interviews with women who have fibromyalgia and found that the ultimate usefulness of the diagnosis is "giving medical representation to an individual's subjective distress."

Photo courtesy of Timeless, Infinite Light

A woman's lived experience is so often denied. Berkowitz experienced this firsthand when she went to the doctor's office for her mysterious shoulder pain. "The doctor was very dismissive and rude to me," Berkowitz recalls over the phone. "It was the first time I felt like I had to stand up to a medical professional and tell her to stop speaking to me that way."

After leaving the doctor's office in tears, Berkowitz went home, her mind reeling from the experience. In bed, she remembered an event that she had repressed for ten years. "As I was lying in bed, before I went to sleep that night, I recalled being raped by my pediatrician when I was about ten. The next morning I woke up and I had pain all over my body." She then sought out a different medical professional and was diagnosed with fibromyalgia, which, she admits, happened quicker than it does for most.

In her book, Berkowitz links her pain to her rape. She believes that her bodily discomfort stems from its traumatic memory. "I very much believe that memories or trauma in your brain affect biological processes," she says—and she's not wrong. While doctors insist that fibromyalgia has no conclusive origin in the body, many studies correlate the condition with traumas like PTSD and rape in adolescence.

This, in part, could explain the higher incidence of fibromyalgia diagnoses in women compared to men; "women [are] more likely than men to develop a chronic pain syndrome after experiencing trauma similar to that experienced by men," Diane E. Hoffmann and Anita J. Tarzian write in their analysis of the gender bias in the treatment of pain, "The Girl Who Cried Pain." Or, in other words, women are more likely to experience somatic pain—like that which characterizes fibromyalgia—as the result of traumatic events. A recent study found that, compared to 28 percent of healthy women, 51 percent of women with fibromyalgia reported they had experienced "very negative childhood or adolescence life events."

If you feel awful and people react with disbelief, that's infuriating.

On her blog, Giulianna Rigali writes about how she was raped by a stranger while she was out walking as a teenager. Eight years later, she writes, she was raped again. In 1997, she started experiencing pains in her wrists and shoulders. "However, after the birth of my 4th child, in 2001, the pain spread throughout my body," she tells me over email. "I could not get out of bed without being crippled up in pain. I could barely walk or form sentences." She also suffered from PTSD in the form of sleeplessness and fatigue. In 2001, she was diagnosed with fibromyalgia. Now a 49-year-old mother, she is currently working with her doctor to manage her condition. "Knowing the diagnosis was the first step in recovering my life," she says.

Though as fibromyalgia has gained more visibility throughout the years, men, too, have started to seek out the diagnosis for their unexplained pain. Norman Hanley, who was diagnosed with fibromyalgia in 2013, moderates the Facebook page Fibro for Men. "Around 2009 I stopped being able to get a good night's sleep, but I thought that was just part of getting older in life. I told myself to just man up," Hanley tells me over the phone. "But I started to see my performance at work go down—I was in traveling sales, but soon I was just too tired to keep up. Eventually I had to quit and try to find something that didn't require too much travel."

Six months later, at a new job, Hanley's condition only worsened. A Marine veteran, he went to the VA, and the first doctor he saw told him that he had nothing wrong with him—it was all in his head. After doing some more research on his own he went back to the doctors and asked about fibromyalgia. "My doctor said, 'Well, you might have that, but really, fibromyalgia is a woman's disease," Hanley recalls. Following that visit, he bounced around from doctor to doctor for a year and finally received a diagnosis of fibromyalgia from a chronic pain clinic.

The website that Hanley also moderates, Men With Fibromyalgia, highlights similar stories from men who suffer from overwhelming pain with no biological marker. The site's purpose, as its name would suggest, is to raise awareness for men with the condition; so far, it seems to be working. This year, the CDC acknowledged that one in seven men suffer from fibromyalgia—up from one in eight in 2014. "Talking with other men in support groups, I've seen that a lot of doctors believe that fibromyalgia is strictly a woman's disease, or, even worse, [that] it's not real at all," Hanley says.

Nortin M. Hadler, a professor of rheumatology at the University of North Carolina at Chapel Hill, explains the complicated nature of diagnosing a patient with fibromyalgia, which he calls a "socially constructed disease." "This is a very difficult subject to talk about," he says, "largely because its an issue in semiotics—what do we mean by the word fibromyalgia? What do we mean by the word disease? One of the sadnesses of this topic is that it tends to devolve into blaming the victim. If you feel awful and people react with disbelief, that's infuriating."

"But there are no bad people here," he continues. "There's a need to better understand the experience of illness for a large number of adults—and some children—who just feel awful."