Julie Rehmeyer had always been a strong, active woman. She regularly ran and hiked in the hills around Santa Fe, New Mexico, where she’d built her own house out of straw and mud. But in the summer of 2000, the mathematician turned science journalist began to struggle with exercise and eventually simple movement, to the point that she ended up paralyzed more than a mile away from home on multiple occasions. She was diagnosed with chronic fatigue syndrome (also known as myalgic encephalomyelitis and by the acronym ME/CFS), a mysterious disease that’s defined mainly by a crippling feeling of exhaustion that doesn’t go away with rest or sleep.

Rehmeyer—and nearly every other ME/CFS patient at the time—struggled to find an effective cure, trying everything from cocktails of supplements to Gatorade. Desperate, she turned to mold avoidance, which she heard about through a forum for ME/CFS patients. As part of this process, Rehmeyer camped in the hot, dry Death Valley, free of her supposedly contaminated belongings, to cleanse herself of toxins. The theory went that if she returned to her typical environment and experienced a wave of strong symptoms, this indicated not only that the building or property was infected with mold, but also that mold triggered her illness. (Or so claims a small group of those with ME/CFS, known as “moldies,” although not enough medical research has been conducted to back it up).

Through the Shadowlands: A Science Writer’s Odyssey Into An Illness Science Doesn’t Understand, published a few weeks ago, is Rehmeyer’s story of the bizarre events that led to her self-identification as a moldie—and how her life was ultimately transformed as a result. We caught up with the author, who now spends about a week per month in Boulder with her husband, to get some insight on a few of the ideas in her page-turner debut of a book.

Julie Rehmeyer and her dog Frances. Courtesy of Julie Rehmeyer

On her reluctance to accept mold as the trigger for her symptoms: I was in a pretty desperate situation by that point. I was so sick I often couldn’t turn over in bed. I was running out of money; I could barely work; I’d gone to the top specialists. It was really dire. In that situation, it was like, ‘I’ve run out of reasonable things to pursue, so the only options that I have are unreasonable ones.’

But then the personal experience was so compelling that I couldn’t ignore it. I could put a backpack that had been in a moldy building on my bed for like five seconds and take it off, go to sleep, and wake up paralyzed because of the backpack that hours earlier had sat on the sheets for five seconds. Really? If I got up and took a shower and changed the sheets, then I felt fine, and if I didn’t, then I spent the whole next day in misery. You have that experience a few times, it’s like, ‘OK, OK, I’ll take the damn shower.’

On rediscovering spirituality: The experience as a whole definitely left me feeling more spiritually connected. By nature, I had a pretty strong sense of spirituality, but when my mother died, I packed that part of myself away to a very significant extent. That’s when I started pursuing mathematics. When I went to Death Valley, though, I couldn’t keep going the way that I had. I realized that the way I understood the world might come to an end, but I was still alive, still breathing. It felt like I could release all the expectations I had about my life, all the sense of obligation that I had, how I defined success and failure—suddenly it was like, ‘OK, just being alive is success. One breath after another is jubilation.’ That was a hugely profound experience.

On the moldy locations she avoids in Boulder: Target is pretty bad. Or the DMV. That’s a funny story because I had talked to other moldies, and they mentioned not to go there, but I forgot about it until John [my husband] was out of town and his registration was expiring. I went there and was like, ‘Oh, oh, I have to get out of here. Oh, right, they told me that.’ But Boulder’s not too bad otherwise, which sort of makes sense because there’s a lot of money so buildings get maintained better. And it’s dry.

On her level of confidence in both scientific research, given the dearth of information about ME/CFS: There’s the reality of science and its flaws as a human institution, but there’s also a kind of ideal of science. In a certain way, the brighter that archetypal ideal, the darker the failings are going to be. That’s part of the deal. The truth is I think the majority of science is not really very good, which is kind of a shocking thing to say. But when it is really good, man oh man do we need it, and is it ever really good.